Yes you absolutely can run slicks with more than 100% Anti Squat!! Not as crazy as Radials, but I do believe you can put the movement of the proper bar angles to help plant the slicks while moving the car forward. For sure, you can fight the squating nature of less than 100% Anti Squat as well and have traction. My thought is if I have to pick one or the other, I will start with more than 100% Anti Squat as that rear separation is a more productive use of the forces being applied on the hit and the entire run!! Bar angles in relation to the Anti Squat line, coilover spring rates and length, shock installed height, proper compression and rebound valving and settings, and air pressure all come to the party to create a balanced approach to drag racing launch!
Kevin you have taught me a lot on suspension thanks to your information I’m successfully hooking on a radial at the track ( adjustable coilovers, traction bars on leaf springs Sierra 14’ ) now I’m watching your videos so I can be successfully hook at the street with slicks keep up the good content
Miguel Leon thanks so much for your kind comments! I am glad to hear you are getting value from the videos! I hope to demystify as much as possible so racers can keep growing our sport! Would love to see some pics/videos of your ride! Go fast, go straight! Be Safe!!
@@KevinWilsonSBC how can I send you more pictures I’m sure all these truck guys from Cali are interested all I see is trucks squatting off the line ! My email is miguelleon92@gmail.com
@@miguelleon6914 my email is on my web page at samsonperformance.com Most of the time YT will block comments with an email address in them. Your comment above was caught by their spam system.
Your videos are killer..thank you my brother....I have a 2002 mustang tube chassis brand new...from a to z I'm going with your advice..I'll make video of results
Just wanted to say set up a new car build 29.5 x10.5 car. nailed it first time with all the information learned from these videos! 1st pass was fastest 60' and it is above anti squat line.
This is exactly why I make suspension videos!!! I needed to hear this today, so thank-you for taking a few minutes and leaving a positive comment. And you are a subscriber to my channel, which makes this even better. Go fast, go straight! Be SAFE!
Wow when I started racing 40 years ago we didn't have any of this stuff and we have to figure out how to drive those cars great stuff now I do a little stop light to stop light street racing and show but this is good stuff if I get back into it I'll look you up in person thanks again
Running slicks the tire starts driving over it’s self when you get the lower bar angle running up hill too much. You get more bite by running it slightly down hill. With radials it’s a whole different ball game, no matter how much force you put on a radial . It will spin before it tries to drive over it’s self.
When anti-squat is tuned well, it's awesome. Get up to a roll, lift, and hit it. When you don't have much anti-squat, you'll find that it's easier to burn rubber from a roll. The car feels compliant. When you're dialed in with more anti squat and a damper with a little bit of bypass in it, the feel is killer. The car takes a proud stomp forwards. It makes you feel invincible. --This experience is interesting in an off-road situation. I had a YFZ450 and that bike had a lot of anti-squat in its swingarm design. It would gain 3" of ride height as it lurched forward. Glorious handling bike! I want my truck to be like that thing.
Thank you once again for sharing this information. I just started with a fox body and as I got it , it has a lot of separation. I started with loose separation I can see that I need to slow it down . Watching your channel has confirmed my thoughts. Also, I watch a lot of no prep and some of these guys are getting 4 plus inches of separation even on crap surfaces. I think I;ll pick up a tenth on my second outing . Again thank you for detailed information
Sorry for your loss I also what to thank you for all your videos very helpful getting my suspension right cant wait for more information to come thanks
Like to chime in. If its pounding the sidewalls just add air pressure. I heard you mention "16psi in radials" well that's where people should start out on slicks when running anti squat. Its gonna drive the rear tires into the ground so make sure you're adding air pressure. Tire shake and tire chatter is mostly low tire pressure. Slicks can act just like a radial you just have to run more air pressure. Keep adding every pass until it finally spins then back them back down some. My general starting points are full loose rear rebound, 5-8 clicks from loose rear compression, and 15-16psi in the tires. Then add to everything throughout the day except rebound unless it has excessive separation.
What I mentioned is per small tires not steam rollers but, steam roller "big tires" benefit from more tire pressure also. DONT BE SCARED TO ADD TIRE PRESSURE! It's free E.T.
Thanks James Hall for taking the time to comment! What HP/TQ levels are talking about with these slicks? Usually around 12 psi on my big tire slick we run into pretty severe tire "bounce". See my video from actual track testing at th-cam.com/video/pQiFzbGy4BM/w-d-xo.html Go Fast, Go Straight! Be Safe!
If its bouncing the tire add more pressure. That bounce will make you chase your tail trying to adjust and change other things. I've helped low power (500) and high power cars (2000) and have them all add pressure. That bounce of the tire will: Hook, bounce, then spin or go into tire shake "chatter". Basically little to no sidewall wrinkles should be visible during video. Especially if the surface is good. I help with street, no prep, back of the track, and glued surfaces.
also I didnt mention too much squat of the sidewall creates the wheelie process and power and leverage makes the wheelie worse. Especially if you have a power adder. Took a quick glance at the video of the Ford. May need to get a revalve for your rebound if on the rear if you cant slow it down anymore than that. Also it definitely needs more air pressure. Next time out go to 16psi and test it. Keep adding air until it spins immediately (with no bounce) and then youve found your sweet spot per those settings.
Just found your channel recently, awesome source of info and finally getting a solid above average understanding of what’s going on with rear suspension. Towards the end of the video when you were talking tire pressures, is that referencing small or big tire cars? Thanks for what you’re doing man, keep it up!!
apodbielski913 thanks so much for your comments and question! At a high level small or big tires can follow the same principles around air pressure. Go fast, go straight! Be Safe!!
If the slick does not crush when separation occurs, and holds with little to no wheel speed (spin) does that translate to more front end separation? rotation front to rear? ie trying to wheelie? Thank you Kevin for sharing your information and experience
Great video . we are on the same page, i tune a lot of peoples cars and i have been setting their cars up with radial inspired setups with slicks for a long time. i have a Turbo chassis car/Blazer that leaves like a nitrous car and no body out 60 foots me on the street. Belfab Race Cars
Jamie Belfiore thanks so much for your comments and feedback on your experience! I would love to connect with you and learn more about your setup on the Blazer! Great connecting with you. Go fast, go straight! Be Safe!!
Love all the videos thank you so much for all the knowledge! What about 4 link setups on street conditions, where you need squat and weight transfer to keep it hooked up?
Chelsea McGill thanks so much for your comments and question! True street racing has required us to use less than 100% anti squat values but each car is so unique it really depends on each car and the amount of power on the hit, then toward the top end. Do you have a street car with 4 links and slicks? If so, I would love to get some more feedback from you since there are times we have had to go this way. Go fast, go straight! Be Safe!!
@@KevinWilsonSBC im installing a 4 link under my stroked 403 turbo 54 chevy now. We've always used ladder bars,but I'm changing up to a 4 link setup and its all new to me and your videos have been a huge help understanding how they work. I have 390# of weights in the rear to help with traction and hoping the 4 link will allow better transfer and I can shed some weight off of it. Always trying to get faster
Can you please go into more detail about Cal trax systems. I've watched you other video And I'm real interested in leaf springs and 4 link combo. Thx. Love your content.
Hi Kevin, Ive been watching your videos and have a few questions.. I run a Suspended Top Dragster. The car typically runs in the high 4.20s. I run a Mickey Thompson 3197 "Big Bubba" tire. The engine makes about 1350 and the car weighs 1875 with me in it. I have 2 Penski canister style double adjustable shocks built by Eric Davis at Penski. My car seems to be very consistent, and does separate on the hit. It separates about .400 from the hit to the 1/8 mile stripe. Not all at once. The initial hit is about .125 then it slowley increases. My question is with a 250" dragster with no front suspension where would you like to see the IC? My bar angles with me in the car are about 1.5 degrees down on the bottom and about 12.5 down on top. I don't believe that would be below the squat line but it does still separate. Im interested to see what you think about this setup Thanks, Mike Sullivan
I'm new and just starting out drag racing. This is my 3rd summer having fun up here in Alaska! Love the channel, very well explained for beginners such as myself so THANK YOU BIG TIME!!! We don't have hot days or a rely good prepped track. My question is. Old timers say slicks but Ive started hooking decent on a drag radial. Is it more of a preference, and is there a margin or geometry error more so on a small tire slick than drag radial? I want to buy a new set of tires this year and IM debating a slick or new radial :) Forgot to add Im in a 1980 Malibu 9 sec cararound 1k HP to the ground on the dyno. Th400 Trans brake supercharged small block. Viking double adjustable coil overs. 2800lbs
Hi Kevin! Thanks you much for the instructional video. Solid info! But in my case I don’t have a 4 link, but a Torque arm with 2 LCAs, so how do I work with the IC? Thanks!
Your videos are great and the presentation is clear and concise, thanks for that... All of the static descriptions are easy to see but understanding how it all work dynamically is where it gets tricky Perhaps a power point animation could be put together which could show how the IC point varies with ride height and how the AS line can vary with sidewall compression and how the torque application, weight transfer and varying surface conditions effects all of it. LOL just kidding... Thanks again for another great video.
Junkyarddawg Fixit thanks so much for your comments and humor! I am trying hard to get racers thinking about their own cars and better understand how to keep improving. Go fast, go straight! Be Safe!
Good videos Kevin. I do feel like I need to add something though. This all applies to people bracket racing, looking for a dead hook on the tire. However, maximum acceleration occurs between 20-35% tire slip on a Drag Slick. This can be proven by looking at a G-Meter. To do this on a well prepped track, you NEED squat to induce tire spin. Ideally, you would use the wheelie bars to do this, and set the 4-link up to stay 100% neutral. Almost every fast Big Tire car (Pro Mod or Outlaw) uses this strategy for a much quicker 60' and ET. You try to manage power to keep the tire spinning at the optimal slip as long as you can, or as long as you have the power to do so. That is the fastest way to get a car down the track, BUT it is not easy. Just figured I would throw this in here because it does apply to the very high HP cars of today.
MRC Tuned thanks so much for your comments and good info! As you get up on more and more power with slicks, I absolutely agree with the wheel speed on slicks. This makes the front and rear shocks valving so critical to keep control of the car. Thanks so much for taking the time to leave a comment! Go fast, go straight! Be Safe!!
kevin i have 64 c10 shortbed with stock single trailing arm .is there a caculator that will work with this type of rear suspension to get percentage of rise or squat. thanks marvin
Love your channel man! So full of information, thanks for sharing. Do you have a video on how to determine how much air pressure to start with with slicks? Thanks in advance 👍🏽
MrElPoderozo1 thanks so much for your comments! That is a tough one to answer as so many factors are at play. Can you give me more details on the car? Go fast, go straight! Be Safe!!
@@KevinWilsonSBC Thank you so much for taking the time to answer. I was just wondering how does one determine how much tire pressure should be used when switching to slicks? I have a 1983 Toyota Corolla with a 4 cylinder/ 80mmTurbo, 5 speed G- force clutchless trans.with a Ford 9" spool, 32 x14.5 x15 Good years. The Wheel base I believe it is 93". You can see it in my channel if you like. Another thing I would LOVE to learn from you would be how to determine the height of the center of gravity on a 4 cyl.? I don't know why but I have always love to learn how to scale and adjust a 4 link, I find it to be very fun to do, lol. Please don't feel like you have to answer me right away, I understand that people have their own lives and are busy, answer when you can and thanks again 👍🏽.
Can you recommend some books to read to more understand i meN i have a real good idea of what's going on and I will orob watch this a few more times great stuff man
nitro 1 thanks so much for your comments and question! I will have to do some digging around on books. I have learned it the hard way with lots of mistakes.... LOL. Thanks for leaving a comment! Go fast, go straight! Be Safe!!
Well I thought I knew but just enough now inhave a big tire noprep and a s.all tire the small tire is a s 10 ladder bar pretty easy until tou through 1800 hp at it big tire I am learning just like you I am so glad I found your site I did find you web page me and guys at the shop are going to definitely keep you in our pocket this year for sure seems cheap enough I know enough to do a call glad someone is doing this
Question about 26:50. How does spring rate affect the rate of shock extension with anti squat? I understand the idea of increasing the extension dampening of the shock to slow the separation, but I'm not sure how the spring plays a part in that? In my mind if a car is sitting on a 200lbs per inch spring, or a 500lbs per inch spring, I'll still use the same force to lift the body of the car 1 inch correct? Spring rate would only affect the dynamic weight on the slick during weight transfer to the back, correct? Not how fast the pinion rotates and extends the shock during the initial launch?
Englishracin thanks so much for your comments and questions! It is all about the stored energy a lighter spring has stored at rest vs a stronger spring at rest. It is backwards than what most think. A lighter spring will compress more on a given car than a stronger springer at rest, therefore storing more energy per pound which helps the shock extend quicker on the hit. You can take a car with a 150 lb spring and install a 110 lb spring to help it separate more quickly. That is a general example, but the theory proves out everytime. Go fast, go straight! Be Safe!
Kevin Wilson How do you determine if it separates faster? The lighter spring would travel further, but I don’t see how it would make it faster. How would a spring with a greater force of pounds per inch extend slower than a softer spring? I’ve thought about this more and do realize it affects it, but I don’t understand how it affects it the way you are describing.
Great presentation on how you want at least some tire/body separation. I have an old school super gas camaro with ladder bars so my bar adjustments are limited. I don't seem to be getting any tire/body separation or seem to be hitting the tire hard like other ladder bar cars do so your videos will help me look into why. Thanks.
sanger440 thanks so much for your comments! Definitely use the videos to help you see what is going on with the ladder bar setup. Depending on how the brackets are located can limit you for sure. Hang in there and don't give up! As you move the front chassis mount up on your ladders bars you will increase the separation on the hit. Just remember your pinion angle as you move the front mount.Go fast, go straight! Be Safe!
Question about cars running big tire slicks on a front wheel drive car. Under acceleration the rear tire and chassis are moving together instead of opposed but as I understand it the anti squat calculation is still the same. Is this correct? Can you still run a high anti squat to minimize the anti lift on the front since the anti lift angle will increase as the back comes up? I can’t see any physics model that would cause the front to squat so this is the only model I see to minimize the front end unloading. Is my thought process sound? And would it still benefit from longer or shorter side view swing arm?
Alan Phillips thanks so much for your comments and questions about front wheel drive! This is an area where I have to admit I am not the best to talk with about front wheel drive cars with slicks. I have ZERO experience with them. I see where you are going, but I am not much use to you on it. Front wheel drive cars have an enemy of weight transfer to the rear, so anything you can do to plant the front slicks and resist rear squat will have to help and not hurt. Getting the COG as far forward & low as possible will also help in my mind. Sorry about the lack of quality suggestions on my part, but I am just honest to the bone. Go fast, go straight! Be Safe!!
@@KevinWilsonSBC theoretically do you think a racing 4 link on the back should behave the same no matter wether it’s FWD or RWD? Like I’m thinking if they put a solid axle on the back but gut it so there’s no parasitic losses from the gears then theoretically it should still pitch up and forward the same as a RWD car until it lifts and unloads. The part about the axle trying to move the opposite direction of the body causing squat that made me start to wonder if I’m missing something. BTW thank you for the reply! I’m home bound with a neuro degenerative disease so I don’t have contact with anyone to spitball engineering ideas anymore. Not much mental stimulation these days.
@@KevinWilsonSBC not sure if you’re interested but I did a lot more research and for a FWD car the anti squat line is parallel to the rear wheel drive anti squat line but it’s vertically offset so it goes through the rear tire spindle as opposed to the rear tires contact patch.
Kevin Wilson Im glad I stumbled across your videos. I just started watching yesterday. So you talk about slicks and drag radials. I was wondering how you classify the Hoosier Quick Time Pro tires? Which way would you suggest to set the anti squat for the QTP tires - more towards the slick or radial setting? I run the QTP 27x11.5x15. I noticed the QTP likes around 15-17 lbs air pressure (pressure measured before burn out). Car is a 70 Cougar 520hp/450tq at flywheel. I have the Calvert stock height split mono leafs and the CalTracs bars and weighs 3110 lbs with me I have always had the bar in the lower hole. Shocks: for 12 years I ran the same set of Lakwood 50/50 rear and 90/10 front. They wore out so my buddy gave me his from his 69 Cougar but have not tested yet due to no time. I now have the Rancho 5 way adjust rears and Calvert 90/10 front. I know the info I gave you is less than what you probably need but im just curious. Again, great info man. --Matt
nova467spanker thanks so much for your comments & questions! We ran the QTP's on the 48 Ford when we drove it on the street early on, 31x13.5 - 15's. We never ran that much air pressure, we were closer to 10 - 11 PSI. I would definitely err on the side of slick settings, but at your power levels and weight, I would likely give the upper hole a try up front for sure. We ran the 48 Ford all the way to 6.45's in the 1/8th mile on those QTP's and then switched over to full slicks. I did find on the QTP's they liked a big and hard burnout. Back then the 48 Ford Coupe was 3435 lbs with a 15:1 383 small block chevy gen1, turbo 400 with transbrake and and 4.30 gears with a 1050 Pro Systems Carb on methanol. Back then we ran the single adjustable coilovers from QA1 in the rear and calvert 90/10's up front. Go fast, go straight! Be Safe!!
@@KevinWilsonSBC Thank you for your response. So far my quickest 1/8 times with the current 3000 stall are back to back 7.2@95mph. The 60ft are only 1.63 though with old Lakewoods and factory pinion angle. I also put 2 degree wedges in along with those shocks I mentioned. Im 230lbs, Before to set the CalTrac bars I pre-loaded the passenger with 2 flats and picked up a Cleveland bare block and put i the driver seat. Then I put a set of bare 4v Cleveland heads and a Cleveland crank on the floor board. Then I tightened the divers side the same as passenger side. The car has always gone strait but I need to see how it reacts with the changes. After I make the car hook and strait, then I can put the 5000 stall in my buddy made for me. Engine will be much happier then and I'm hoping with the suspension and stall to be in the 6.7-6.8 1/8 mile times. That's quick enough for this car. When I get to test again i will test the way I always have with the bars on the lower holes. Mainly to see the difference from old stuff to new parts. Then I will change my bars to the top hole like you suggested and see if wants more tire hit. I dont care or want to do wheelies, just want car to go out , strait and fast safely as possible.
@@KevinWilsonSBC I have a few videos but not close up. These 2 kinda show how the front end rebound is and you can kinda see the rear squat. Both videos are same day and nothing changed. Only thing different was on the second run the engine temp was creeping up. Thats why I rushed staged him. Second video the rebound knocked the tires off a bit but slow motion shows I pulled the wheels a little bit on the hit. Video 1 th-cam.com/video/o5tG0J_etNk/w-d-xo.html Video 2 th-cam.com/video/LvUSns_ZkFg/w-d-xo.html
If you have to much anti squat will it cause tires to spin ? I have a friend who has a fbody I have one as well , we have same shocks up front I set his to mine , I cut 1.5s he cuts 2.1s both stick turbo cars with relative same power ,
blownaway14 thanks so much for your comments! Too much AS will definitely hurt your 60'. It is a balancing act for sure. Go fast, go straight! Be Safe!!
Great video 👌.. I will likely need to watch several times to truly understand.. my situation ma be a little bit unique, I have a 75 Cosworth Vega with the fuel overhead cam 2.0L. I'm hoping to do some drag racing with it next year (covid permitting 😅) and wonderuhow much it would benefit me to change the lower control arm angle to provide anti squat.. I'm only making about 150 hp but my torque is around 110lbft😢 so I would be leaving the light around 3500/4500 rpm to keep the motor out of a bog situation, but with 13" tires traction is now the issue.. being a torque arm suspension can I get away with just lowering the control arm at the axle and maybe adjustable shocks to achieve more traction on a street tire or would I just be pissing into the wind.. again..great vid👍
bob762231 thanks so much for your comments and questions! I would definitely give the changes you discussed a try for sure. Go fast, go straight! Be Safe!
Fix it Fix it thanks so much for your question! Not sure I am following you. My apologies. Are you talking about a front wheel drive car with a slick? Go fast, go straight! Be Safe!
Kevin Wilson thanks Kevin running slick all around car come in at 1020 kg ready with 275kg on left front and 295 on right front with 15psi they look flat can I run more it’s a right hand drive car cheers thanks for the videos
Would you stay with this theory on bad/no prep surfaces? I have the car working somewhat well on drag radials on a marginal track. But I’m moving to Hoosier c07 slicks and worse surfaces.
Hi Kevin, Awesome videos! How would you set up a ladder bar car on 10” QTP’s running on virgin streets? Heavy G body at 3600 lbs with 1000+hp. Right now I’m at less than 100% anti squat and having a hard time getting it to hook. On virgin streets what would be more important.... weight transfer or anti squat?
Les Omori thanks so much for your comments! Go to my website for Samsonperformance and get me the info on the suspension tuning PDF file so I can help you based on your car's current settings. Go fast, go straight! Be Safe!
I think u can get better 60ft closer to 100 percent squat because if you hook you will waste alot less energy if you dont squat or seperate wheels from body.
George Dunn thanks so much for your question! That generally leads to a loss of traction. It is a balancing act of planting the tires at the right amount. Go fast, go straight! Be Safe!!
Hello Kevin...What you say make perfect sense with something I had heard many years ago which was to pull up on the wheel opening and then push down on the fender. Your feet are experiencing the load between the tire and track. To get the best traction you want the tire to wheel arch to separate (pulling up not pushing down). I believe I heard you say, but maybe not in so many words, that for both a radial and a slick you want separations at the rear and not squat. Is that correct? If you have a multi-link rear suspension (modern factory stock) do you also want separation or is squat needed? It seems like most if not all cars with unmodified suspension have squat on the left rear. Is it possible to have separation with a modern factory multi link suspension? Thanks and BE SAFE
john casey thanks so much for your comments and question! I am generally looking for rear separation to some degree even with slicks. Radials must have separation. Remember all the parts need to be working together, especially the rear ARB to help control chassis leaning left to right. Go fast, go straight! Be Safe!!
@@KevinWilsonSBC Thanks Kevin. The memory fog is starting to clear a little. Let me go back and study more on your anti-roll bar adjustability vid. Are there fundamental differences between solid axle and independent rear suspensions that affect the way things work in solving a traction problem (tire and wheel bounce)?
Hermann Douglas thanks so much for your question! IC height does play a part in the cars reaction as different IC heights will dictate IC length. I cannot really comment on a 9" IC height without a bunch more info, but if 9" also falls on the AS line then you will have 100% AS and then you can test. Go fast, go straight! Be Safe!
Travis Sowell thanks so much for your question! Just released the ladder bar video at th-cam.com/video/HF9cvi4I_OU/w-d-xo.html so check it out! Go fast, go straight! Be Safe!
32 Roadster thanks so much for your question! You can get in touch with me from my website samsonperformance.com and use the email there along with the drag car suspension setup sheet. Go fast, go straight! Be Safe!!
Hey Kevin, forgive me if you have already covered my question in a different video. How much of this video applies to a ladder bar car? And if it doesn't apply, can you please do one like this for a ladder bar car.
Tommy Waters thanks so much for your question! Anti squat percentage and slicks applies to ladder bar cars as well. Checkout th-cam.com/video/HF9cvi4I_OU/w-d-xo.html Go fast, go straight! Be Safe!
Talking about "setting" "Bar-Angles" is completely absurd. The location of the imaginary "Instant-Center" is what counts, how you achieve that is almost irrelevant. If you have reasonably long Suspension Travel, (which you should), the Instant-Center will MOVE from less than 100% to more than 100% as the Car Body rises. The distance between the Rear-Axle, and the Center of Gravity of the Car, should be expressed as a PERCENTAGE, not necessarily how many "Inches", when referring to how "long" the Instant Center is. A smaller percentage of that distance results in a more violent, and much shorter in duration, "Hit" to the Tires. A larger percentage of that distance results in a softer, but much longer, application of additional, temporary, "Effective-Weight" being applied to the Tires. Here is what you are trying to achieve in the long run .......... You are trying to lift the entire car off of the ground by using the Torque of the Rear-Axle. This applies MORE-THAN the full weight of the car to the Rear Tires .......... Until the Suspension "Tops-Out". The Front Tires need to be off the ground just BEFORE the Rear Suspension "Tops-Out". Both the Front AND Rear Suspensions should "Top-Out" at "almost" the same time. The Front Suspension needs to "Top-Out" slightly BEFORE the Rear Suspension. They must both "Top-Out" smoothly, this comes from the Rebound Settings of the Shocks. If they don't "Top-Out" smoothly, the entire Car will try to jump off of the ground, and you will instantly blow-away the Tires.. Preferably, the "effective" Spring-Rates of your front and rear springs, AND the amount of suspension travel, will be equal for both the Front AND Rear Suspensions. Normal Ride Height should provide approximately 25% Compression Travel, and 75% Rebound Travel from "normal" ride height. On a Drag-Only car, you may want to go even less, to ~20% / ~80%. Softer Spring-Rates will allow for the "possibility" of a less violent initial "Hit" to the tires, AND will extend the time and distance created by a softer "Hit". Higher Spring Rates make everything much more critical, and harder to tune. More Suspension Travel is almost always better. The Suspension should NEVER "Bottom-Out" , for any reason, if it does, increase Compression-Damping until it doesn't. This will also reduce potential parts breakage. Shocks are your best friend. Never-Ever scrimp on Shocks. Get the very best that you can afford. The Shocks are what keeps everything under control. A harder, more violent "Hit" may actually cause a LOSS of Traction by "Crushing" the Tires too hard and too fast. An extremely violent "Hit" can put more than 3-TIMES the weight of the Car on to the Rear Tires. If you "Blow-Away" the Tires BEFORE the Front Tires are off the ground, you're probably doing something wrong with Suspension Set-up. If you "Blow-Away" the Tires AFTER the Front Tires are off the Ground, you must reduce power for Track Conditions, OR, find a way to get more Traction .... ( Tire Compound, Tire Pressure, Tire Size, Rim-Width, Burn-Out procedure, etc. ) ( You may also be "Topping-Out" the Rear Shocks ) A Side-View Video of the Car leaving the Line is your most valuable Tuning-Tool, along with an extensive Data-Acquisition-System. The Car should rise EVENLY, FRONT AND REAR, for as much Distance / Time as possible. . . .
Yes you absolutely can run slicks with more than 100% Anti Squat!! Not as crazy as Radials, but I do believe you can put the movement of the proper bar angles to help plant the slicks while moving the car forward. For sure, you can fight the squating nature of less than 100% Anti Squat as well and have traction. My thought is if I have to pick one or the other, I will start with more than 100% Anti Squat as that rear separation is a more productive use of the forces being applied on the hit and the entire run!! Bar angles in relation to the Anti Squat line, coilover spring rates and length, shock installed height, proper compression and rebound valving and settings, and air pressure all come to the party to create a balanced approach to drag racing launch!
Can you work on my car?
Still great videos Thank you I really enjoy them and keep watching them to get a better more in-depth understanding how all of this works together
Kevin you have taught me a lot on suspension thanks to your information I’m successfully hooking on a radial at the track ( adjustable coilovers, traction bars on leaf springs Sierra 14’ ) now I’m watching your videos so I can be successfully hook at the street with slicks keep up the good content
Miguel Leon thanks so much for your kind comments! I am glad to hear you are getting value from the videos! I hope to demystify as much as possible so racers can keep growing our sport! Would love to see some pics/videos of your ride! Go fast, go straight! Be Safe!!
@@KevinWilsonSBC how can I send you more pictures I’m sure all these truck guys from Cali are interested all I see is trucks squatting off the line ! My email is miguelleon92@gmail.com
@@miguelleon6914 my email is on my web page at samsonperformance.com Most of the time YT will block comments with an email address in them. Your comment above was caught by their spam system.
I can't tell you how much your content has helped me tune the chassis on my 9sec street/ strip car Think I found the sweet spot on my anti squat 🙏👍
dan hansen thanks so much for your comments! Go fast, go straight! Be Safe!!
Great video, 3 months ago I just wanted a better tire. As of today I have adjustable control arms and adjustable shocks. World of difference
yoncen5oh thanks so much for your comments! Go fast, go straight! Be Safe!!
You have the best videos on suspension I have ever seen. Great work!!!!
Wow, thanks! Go fast, go straight! Be SAFE!!
Your videos are killer..thank you my brother....I have a 2002 mustang tube chassis brand new...from a to z I'm going with your advice..I'll make video of results
Just wanted to say set up a new car build 29.5 x10.5 car. nailed it first time with all the information learned from these videos! 1st pass was fastest 60' and it is above anti squat line.
This is exactly why I make suspension videos!!! I needed to hear this today, so thank-you for taking a few minutes and leaving a positive comment. And you are a subscriber to my channel, which makes this even better. Go fast, go straight! Be SAFE!
Wow when I started racing 40 years ago we didn't have any of this stuff and we have to figure out how to drive those cars great stuff now I do a little stop light to stop light street racing and show but this is good stuff if I get back into it I'll look you up in person thanks again
Dale Chirstopher thanks so much for your comments! Look me up for sure if you are in the area. Go fast, go straight! Be Safe!!
Running slicks the tire starts driving over it’s self when you get the lower bar angle running up hill too much. You get more bite by running it slightly down hill. With radials it’s a whole different ball game, no matter how much force you put on a radial . It will spin before it tries to drive over it’s self.
When anti-squat is tuned well, it's awesome. Get up to a roll, lift, and hit it. When you don't have much anti-squat, you'll find that it's easier to burn rubber from a roll. The car feels compliant. When you're dialed in with more anti squat and a damper with a little bit of bypass in it, the feel is killer. The car takes a proud stomp forwards. It makes you feel invincible.
--This experience is interesting in an off-road situation. I had a YFZ450 and that bike had a lot of anti-squat in its swingarm design. It would gain 3" of ride height as it lurched forward. Glorious handling bike! I want my truck to be like that thing.
Guns Cars and Digits thanks so much for your comments! Go fast, go straight! Be Safe!
Thank you once again for sharing this information. I just started with a fox body and as I got it , it has a lot of separation. I started with loose separation I can see that I need to slow it down . Watching your channel has confirmed my thoughts. Also, I watch a lot of no prep and some of these guys are getting 4 plus inches of separation even on crap surfaces. I think I;ll pick up a tenth on my second outing . Again thank you for detailed information
Sorry for your loss I also what to thank you for all your videos very helpful getting my suspension right cant wait for more information to come thanks
leonard alkiewicz thanks so much for your comments! More content on the way very soon! Go fast, go straight! Be Safe!
Like to chime in. If its pounding the sidewalls just add air pressure. I heard you mention "16psi in radials" well that's where people should start out on slicks when running anti squat. Its gonna drive the rear tires into the ground so make sure you're adding air pressure. Tire shake and tire chatter is mostly low tire pressure. Slicks can act just like a radial you just have to run more air pressure. Keep adding every pass until it finally spins then back them back down some. My general starting points are full loose rear rebound, 5-8 clicks from loose rear compression, and 15-16psi in the tires. Then add to everything throughout the day except rebound unless it has excessive separation.
What I mentioned is per small tires not steam rollers but, steam roller "big tires" benefit from more tire pressure also. DONT BE SCARED TO ADD TIRE PRESSURE! It's free E.T.
Thanks James Hall for taking the time to comment! What HP/TQ levels are talking about with these slicks? Usually around 12 psi on my big tire slick we run into pretty severe tire "bounce". See my video from actual track testing at th-cam.com/video/pQiFzbGy4BM/w-d-xo.html Go Fast, Go Straight! Be Safe!
If its bouncing the tire add more pressure. That bounce will make you chase your tail trying to adjust and change other things. I've helped low power (500) and high power cars (2000) and have them all add pressure. That bounce of the tire will: Hook, bounce, then spin or go into tire shake "chatter". Basically little to no sidewall wrinkles should be visible during video. Especially if the surface is good. I help with street, no prep, back of the track, and glued surfaces.
also I didnt mention too much squat of the sidewall creates the wheelie process and power and leverage makes the wheelie worse. Especially if you have a power adder. Took a quick glance at the video of the Ford. May need to get a revalve for your rebound if on the rear if you cant slow it down anymore than that. Also it definitely needs more air pressure. Next time out go to 16psi and test it. Keep adding air until it spins immediately (with no bounce) and then youve found your sweet spot per those settings.
Just found your channel recently, awesome source of info and finally getting a solid above average understanding of what’s going on with rear suspension. Towards the end of the video when you were talking tire pressures, is that referencing small or big tire cars? Thanks for what you’re doing man, keep it up!!
apodbielski913 thanks so much for your comments and question! At a high level small or big tires can follow the same principles around air pressure. Go fast, go straight! Be Safe!!
If the slick does not crush when separation occurs, and holds with little to no wheel speed (spin) does that translate to more front end separation? rotation front to rear? ie trying to wheelie? Thank you Kevin for sharing your information and experience
Nice job again Kevin. Gunna have to watch again. Plenty of valuable info
Scott Nettell thanks so much for your comments! Go fast, go straight! Be Safe!
Great video . we are on the same page, i tune a lot of peoples cars and i have been setting their cars up with radial inspired setups with slicks for a long time. i have a Turbo chassis car/Blazer that leaves like a nitrous car and no body out 60 foots me on the street. Belfab Race Cars
Jamie Belfiore thanks so much for your comments and feedback on your experience! I would love to connect with you and learn more about your setup on the Blazer! Great connecting with you. Go fast, go straight! Be Safe!!
Love all the videos thank you so much for all the knowledge! What about 4 link setups on street conditions, where you need squat and weight transfer to keep it hooked up?
Chelsea McGill thanks so much for your comments and question! True street racing has required us to use less than 100% anti squat values but each car is so unique it really depends on each car and the amount of power on the hit, then toward the top end. Do you have a street car with 4 links and slicks? If so, I would love to get some more feedback from you since there are times we have had to go this way. Go fast, go straight! Be Safe!!
@@KevinWilsonSBC im installing a 4 link under my stroked 403 turbo 54 chevy now. We've always used ladder bars,but I'm changing up to a 4 link setup and its all new to me and your videos have been a huge help understanding how they work. I have 390# of weights in the rear to help with traction and hoping the 4 link will allow better transfer and I can shed some weight off of it. Always trying to get faster
Good stuff Kevin. Thank you for all this information.
Oscar Utrera thanks so much for your comments! Go fast, go straight! Be Safe!!
Can you please go into more detail about Cal trax systems. I've watched you other video
And I'm real interested in leaf springs and 4 link combo. Thx.
Love your content.
cooltruckin thanks so much for your comments! I will work on a more detailed video. Go fast, go straight! Be Safe!!
Hi Kevin, Ive been watching your videos and have a few questions.. I run a Suspended Top Dragster. The car typically runs in the high 4.20s. I run a Mickey Thompson 3197 "Big Bubba" tire. The engine makes about 1350 and the car weighs 1875 with me in it. I have 2 Penski canister style double adjustable shocks built by Eric Davis at Penski. My car seems to be very consistent, and does separate on the hit. It separates about .400 from the hit to the 1/8 mile stripe. Not all at once. The initial hit is about .125 then it slowley increases. My question is with a 250" dragster with no front suspension where would you like to see the IC? My bar angles with me in the car are about 1.5 degrees down on the bottom and about 12.5 down on top. I don't believe that would be below the squat line but it does still separate. Im interested to see what you think about this setup
Thanks,
Mike Sullivan
I'm new and just starting out drag racing. This is my 3rd summer having fun up here in Alaska! Love the channel, very well explained for beginners such as myself so THANK YOU BIG TIME!!! We don't have hot days or a rely good prepped track. My question is. Old timers say slicks but Ive started hooking decent on a drag radial. Is it more of a preference, and is there a margin or geometry error more so on a small tire slick than drag radial? I want to buy a new set of tires this year and IM debating a slick or new radial :) Forgot to add Im in a 1980 Malibu 9 sec cararound 1k HP to the ground on the dyno. Th400 Trans brake supercharged small block. Viking double adjustable coil overs. 2800lbs
Slicks are just easier to get hooked up earlier... mainly preference. Go fast, go straight! Be SAFE!
Hi Kevin! Thanks you much for the instructional video. Solid info! But in my case I don’t have a 4 link, but a Torque arm with 2 LCAs, so how do I work with the IC?
Thanks!
Lolo Forge thanks so much for your comments! Checkout my F-Body video. Go fast, go straight! Be Safe!!
Your videos are great and the presentation is clear and concise, thanks for that...
All of the static descriptions are easy to see but understanding how it all work dynamically is where it gets tricky
Perhaps a power point animation could be put together which could show how the IC point varies with ride height and how
the AS line can vary with sidewall compression and how the torque application, weight transfer and varying surface conditions effects all of it. LOL just kidding...
Thanks again for another great video.
Junkyarddawg Fixit thanks so much for your comments and humor! I am trying hard to get racers thinking about their own cars and better understand how to keep improving. Go fast, go straight! Be Safe!
Thanks Kevin your videos are helping me a lot.
Bob Francoletti thanks so much for your comments! Go fast, go straight! Be Safe!
Nicely covered. Is it worth focusing on height of instant center vs axle centerline as much as anti squat line?
Good videos Kevin. I do feel like I need to add something though. This all applies to people bracket racing, looking for a dead hook on the tire. However, maximum acceleration occurs between 20-35% tire slip on a Drag Slick. This can be proven by looking at a G-Meter. To do this on a well prepped track, you NEED squat to induce tire spin. Ideally, you would use the wheelie bars to do this, and set the 4-link up to stay 100% neutral. Almost every fast Big Tire car (Pro Mod or Outlaw) uses this strategy for a much quicker 60' and ET. You try to manage power to keep the tire spinning at the optimal slip as long as you can, or as long as you have the power to do so. That is the fastest way to get a car down the track, BUT it is not easy. Just figured I would throw this in here because it does apply to the very high HP cars of today.
MRC Tuned thanks so much for your comments and good info! As you get up on more and more power with slicks, I absolutely agree with the wheel speed on slicks. This makes the front and rear shocks valving so critical to keep control of the car. Thanks so much for taking the time to leave a comment! Go fast, go straight! Be Safe!!
kevin i have 64 c10 shortbed with stock single trailing arm .is there a caculator that will work with this type of rear suspension to get percentage of rise or squat. thanks marvin
Love your channel man! So full of information, thanks for sharing.
Do you have a video on how to determine how much air pressure to start with with slicks? Thanks in advance 👍🏽
MrElPoderozo1 thanks so much for your comments! That is a tough one to answer as so many factors are at play. Can you give me more details on the car? Go fast, go straight! Be Safe!!
@@KevinWilsonSBC Thank you so much for taking the time to answer. I was just wondering how does one determine how much tire pressure should be used when switching to slicks?
I have a 1983 Toyota Corolla with a 4 cylinder/ 80mmTurbo, 5 speed G- force clutchless trans.with a Ford 9" spool, 32 x14.5 x15 Good years.
The Wheel base I believe it is 93".
You can see it in my channel if you like. Another thing I would LOVE to learn from you would be how to determine the height of the center of gravity on a 4 cyl.?
I don't know why but I have always love to learn how to scale and adjust a 4 link, I find it to be very fun to do, lol.
Please don't feel like you have to answer me right away, I understand that people have their own lives and are busy, answer when you can and thanks again 👍🏽.
Can you recommend some books to read to more understand i meN i have a real good idea of what's going on and I will orob watch this a few more times great stuff man
nitro 1 thanks so much for your comments and question! I will have to do some digging around on books. I have learned it the hard way with lots of mistakes.... LOL. Thanks for leaving a comment! Go fast, go straight! Be Safe!!
Well I thought I knew but just enough now inhave a big tire noprep and a s.all tire the small tire is a s 10 ladder bar pretty easy until tou through 1800 hp at it big tire I am learning just like you I am so glad I found your site I did find you web page me and guys at the shop are going to definitely keep you in our pocket this year for sure seems cheap enough I know enough to do a call glad someone is doing this
Question about 26:50. How does spring rate affect the rate of shock extension with anti squat? I understand the idea of increasing the extension dampening of the shock to slow the separation, but I'm not sure how the spring plays a part in that? In my mind if a car is sitting on a 200lbs per inch spring, or a 500lbs per inch spring, I'll still use the same force to lift the body of the car 1 inch correct?
Spring rate would only affect the dynamic weight on the slick during weight transfer to the back, correct? Not how fast the pinion rotates and extends the shock during the initial launch?
Englishracin thanks so much for your comments and questions! It is all about the stored energy a lighter spring has stored at rest vs a stronger spring at rest. It is backwards than what most think. A lighter spring will compress more on a given car than a stronger springer at rest, therefore storing more energy per pound which helps the shock extend quicker on the hit. You can take a car with a 150 lb spring and install a 110 lb spring to help it separate more quickly. That is a general example, but the theory proves out everytime. Go fast, go straight! Be Safe!
Kevin Wilson How do you determine if it separates faster? The lighter spring would travel further, but I don’t see how it would make it faster. How would a spring with a greater force of pounds per inch extend slower than a softer spring?
I’ve thought about this more and do realize it affects it, but I don’t understand how it affects it the way you are describing.
Great presentation on how you want at least some tire/body separation. I have an old school super gas camaro with ladder bars so my bar adjustments are limited. I don't seem to be getting any tire/body separation or seem to be hitting the tire hard like other ladder bar cars do so your videos will help me look into why. Thanks.
sanger440 thanks so much for your comments! Definitely use the videos to help you see what is going on with the ladder bar setup. Depending on how the brackets are located can limit you for sure. Hang in there and don't give up! As you move the front chassis mount up on your ladders bars you will increase the separation on the hit. Just remember your pinion angle as you move the front mount.Go fast, go straight! Be Safe!
do these principles still apply to a small tire non W slick, Or will you just crush the hell out of it
dan hansen thanks so much for your comments! Principles apply, but you don't want to crush it. Go fast, go straight! Be Safe!!
Question about cars running big tire slicks on a front wheel drive car. Under acceleration the rear tire and chassis are moving together instead of opposed but as I understand it the anti squat calculation is still the same. Is this correct? Can you still run a high anti squat to minimize the anti lift on the front since the anti lift angle will increase as the back comes up? I can’t see any physics model that would cause the front to squat so this is the only model I see to minimize the front end unloading. Is my thought process sound? And would it still benefit from longer or shorter side view swing arm?
Alan Phillips thanks so much for your comments and questions about front wheel drive! This is an area where I have to admit I am not the best to talk with about front wheel drive cars with slicks. I have ZERO experience with them. I see where you are going, but I am not much use to you on it. Front wheel drive cars have an enemy of weight transfer to the rear, so anything you can do to plant the front slicks and resist rear squat will have to help and not hurt. Getting the COG as far forward & low as possible will also help in my mind. Sorry about the lack of quality suggestions on my part, but I am just honest to the bone. Go fast, go straight! Be Safe!!
@@KevinWilsonSBC theoretically do you think a racing 4 link on the back should behave the same no matter wether it’s FWD or RWD? Like I’m thinking if they put a solid axle on the back but gut it so there’s no parasitic losses from the gears then theoretically it should still pitch up and forward the same as a RWD car until it lifts and unloads. The part about the axle trying to move the opposite direction of the body causing squat that made me start to wonder if I’m missing something. BTW thank you for the reply! I’m home bound with a neuro degenerative disease so I don’t have contact with anyone to spitball engineering ideas anymore. Not much mental stimulation these days.
@@KevinWilsonSBC not sure if you’re interested but I did a lot more research and for a FWD car the anti squat line is parallel to the rear wheel drive anti squat line but it’s vertically offset so it goes through the rear tire spindle as opposed to the rear tires contact patch.
Kevin Wilson Im glad I stumbled across your videos. I just started watching yesterday. So you talk about slicks and drag radials. I was wondering how you classify the Hoosier Quick Time Pro tires? Which way would you suggest to set the anti squat for the QTP tires - more towards the slick or radial setting? I run the QTP 27x11.5x15. I noticed the QTP likes around 15-17 lbs air pressure (pressure measured before burn out).
Car is a 70 Cougar 520hp/450tq at flywheel. I have the Calvert stock height split mono leafs and the CalTracs bars and weighs 3110 lbs with me I have always had the bar in the lower hole. Shocks: for 12 years I ran the same set of Lakwood 50/50 rear and 90/10 front. They wore out so my buddy gave me his from his 69 Cougar but have not tested yet due to no time. I now have the Rancho 5 way adjust rears and Calvert 90/10 front. I know the info I gave you is less than what you probably need but im just curious. Again, great info man.
--Matt
nova467spanker thanks so much for your comments & questions! We ran the QTP's on the 48 Ford when we drove it on the street early on, 31x13.5 - 15's. We never ran that much air pressure, we were closer to 10 - 11 PSI. I would definitely err on the side of slick settings, but at your power levels and weight, I would likely give the upper hole a try up front for sure. We ran the 48 Ford all the way to 6.45's in the 1/8th mile on those QTP's and then switched over to full slicks. I did find on the QTP's they liked a big and hard burnout. Back then the 48 Ford Coupe was 3435 lbs with a 15:1 383 small block chevy gen1, turbo 400 with transbrake and and 4.30 gears with a 1050 Pro Systems Carb on methanol. Back then we ran the single adjustable coilovers from QA1 in the rear and calvert 90/10's up front. Go fast, go straight! Be Safe!!
@@KevinWilsonSBC Thank you for your response. So far my quickest 1/8 times with the current 3000 stall are back to back 7.2@95mph. The 60ft are only 1.63 though with old Lakewoods and factory pinion angle. I also put 2 degree wedges in along with those shocks I mentioned. Im 230lbs, Before to set the CalTrac bars I pre-loaded the passenger with 2 flats and picked up a Cleveland bare block and put i the driver seat. Then I put a set of bare 4v Cleveland heads and a Cleveland crank on the floor board. Then I tightened the divers side the same as passenger side. The car has always gone strait but I need to see how it reacts with the changes. After I make the car hook and strait, then I can put the 5000 stall in my buddy made for me. Engine will be much happier then and I'm hoping with the suspension and stall to be in the 6.7-6.8 1/8 mile times. That's quick enough for this car. When I get to test again i will test the way I always have with the bars on the lower holes. Mainly to see the difference from old stuff to new parts. Then I will change my bars to the top hole like you suggested and see if wants more tire hit. I dont care or want to do wheelies, just want car to go out , strait and fast safely as possible.
@@KevinWilsonSBC I have a few videos but not close up. These 2 kinda show how the front end rebound is and you can kinda see the rear squat. Both videos are same day and nothing changed. Only thing different was on the second run the engine temp was creeping up. Thats why I rushed staged him. Second video the rebound knocked the tires off a bit but slow motion shows I pulled the wheels a little bit on the hit.
Video 1 th-cam.com/video/o5tG0J_etNk/w-d-xo.html
Video 2 th-cam.com/video/LvUSns_ZkFg/w-d-xo.html
Amazing information!! Thank you
Glad it was helpful! Thank-you for taking the time to comment! Go fast, go straight! Be SAFE!!
If you have to much anti squat will it cause tires to spin ? I have a friend who has a fbody I have one as well , we have same shocks up front I set his to mine , I cut 1.5s he cuts 2.1s both stick turbo cars with relative same power ,
blownaway14 thanks so much for your comments! Too much AS will definitely hurt your 60'. It is a balancing act for sure. Go fast, go straight! Be Safe!!
Great video 👌.. I will likely need to watch several times to truly understand.. my situation ma be a little bit unique, I have a 75 Cosworth Vega with the fuel overhead cam 2.0L. I'm hoping to do some drag racing with it next year (covid permitting 😅) and wonderuhow much it would benefit me to change the lower control arm angle to provide anti squat.. I'm only making about 150 hp but my torque is around 110lbft😢 so I would be leaving the light around 3500/4500 rpm to keep the motor out of a bog situation, but with 13" tires traction is now the issue.. being a torque arm suspension can I get away with just lowering the control arm at the axle and maybe adjustable shocks to achieve more traction on a street tire or would I just be pissing into the wind.. again..great vid👍
bob762231 thanks so much for your comments and questions! I would definitely give the changes you discussed a try for sure. Go fast, go straight! Be Safe!
@@KevinWilsonSBC thank you😊👍
Excellent video one question on front slick what psi is in range cheers
Fix it Fix it thanks so much for your question! Not sure I am following you. My apologies. Are you talking about a front wheel drive car with a slick? Go fast, go straight! Be Safe!
Kevin Wilson thanks Kevin running slick all around car come in at 1020 kg ready with 275kg on left front and 295 on right front with 15psi they look flat can I run more it’s a right hand drive car cheers thanks for the videos
Would you stay with this theory on bad/no prep surfaces? I have the car working somewhat well on drag radials on a marginal track. But I’m moving to Hoosier c07 slicks and worse surfaces.
nsboost thanks so much for your comments! No Prep suspension video on the way. Thanks for subscribing!! Go fast, go straight! Be Safe!!
Hi Kevin,
Awesome videos! How would you set up a ladder bar car on 10” QTP’s running on virgin streets? Heavy G body at 3600 lbs with 1000+hp. Right now I’m at less than 100% anti squat and having a hard time getting it to hook. On virgin streets what would be more important.... weight transfer or anti squat?
Les Omori thanks so much for your comments! Go to my website for Samsonperformance and get me the info on the suspension tuning PDF file so I can help you based on your car's current settings. Go fast, go straight! Be Safe!
I think u can get better 60ft closer to 100 percent squat because if you hook you will waste alot less energy if you dont squat or seperate wheels from body.
Apache Aguilar thanks so much for your comments! Go fast, go straight! Be Safe!!
This channel should have took off already! Great information
Billy Burgess thanks so much for your comments! Go fast, go straight! Be Safe!!
What happens when you unload the tire
George Dunn thanks so much for your question! That generally leads to a loss of traction. It is a balancing act of planting the tires at the right amount. Go fast, go straight! Be Safe!!
Hello Kevin...What you say make perfect sense with something I had heard many years ago which was to pull up on the wheel opening and then push down on the fender. Your feet are experiencing the load between the tire and track. To get the best traction you want the tire to wheel arch to separate (pulling up not pushing down). I believe I heard you say, but maybe not in so many words, that for both a radial and a slick you want separations at the rear and not squat. Is that correct? If you have a multi-link rear suspension (modern factory stock) do you also want separation or is squat needed? It seems like most if not all cars with unmodified suspension have squat on the left rear. Is it possible to have separation with a modern factory multi link suspension? Thanks and BE SAFE
john casey thanks so much for your comments and question! I am generally looking for rear separation to some degree even with slicks. Radials must have separation. Remember all the parts need to be working together, especially the rear ARB to help control chassis leaning left to right. Go fast, go straight! Be Safe!!
@@KevinWilsonSBC Thanks Kevin. The memory fog is starting to clear a little. Let me go back and study more on your anti-roll bar adjustability vid. Are there fundamental differences between solid axle and independent rear suspensions that affect the way things work in solving a traction problem (tire and wheel bounce)?
How important is IC height when your trying to get around 100% antiisquat? Say the camshaft is 17" off floor is it ok to be towards the 9"s?
Hermann Douglas thanks so much for your question! IC height does play a part in the cars reaction as different IC heights will dictate IC length. I cannot really comment on a 9" IC height without a bunch more info, but if 9" also falls on the AS line then you will have 100% AS and then you can test. Go fast, go straight! Be Safe!
Great information. Many thanks!!
Streetvw thanks so much for your comments! Go fast, go straight! Be safe!
Curious what your thoughts are with setting this method up on a ladder bar car is? I was about to make the switch to radials anyhow...
Travis Sowell thanks so much for your question! Just released the ladder bar video at th-cam.com/video/HF9cvi4I_OU/w-d-xo.html so check it out! Go fast, go straight! Be Safe!
How do i get in touch with you for help with my car?
32 Roadster thanks so much for your question! You can get in touch with me from my website samsonperformance.com and use the email there along with the drag car suspension setup sheet. Go fast, go straight! Be Safe!!
Hey Kevin, forgive me if you have already covered my question in a different video. How much of this video applies to a ladder bar car? And if it doesn't apply, can you please do one like this for a ladder bar car.
Tommy Waters thanks so much for your question! Anti squat percentage and slicks applies to ladder bar cars as well. Checkout th-cam.com/video/HF9cvi4I_OU/w-d-xo.html Go fast, go straight! Be Safe!
Talking about "setting" "Bar-Angles" is completely absurd.
The location of the imaginary "Instant-Center" is what counts,
how you achieve that is almost irrelevant.
If you have reasonably long Suspension Travel, (which you should),
the Instant-Center will MOVE from less than 100% to more than 100% as the Car Body rises.
The distance between the Rear-Axle, and the Center of Gravity of the Car,
should be expressed as a PERCENTAGE, not necessarily how many "Inches",
when referring to how "long" the Instant Center is.
A smaller percentage of that distance results in a more violent,
and much shorter in duration, "Hit" to the Tires.
A larger percentage of that distance results in a softer, but much longer,
application of additional, temporary, "Effective-Weight" being applied to the Tires.
Here is what you are trying to achieve in the long run ..........
You are trying to lift the entire car off of the ground by using the
Torque of the Rear-Axle.
This applies MORE-THAN the full weight of the car to the Rear Tires ..........
Until the Suspension "Tops-Out".
The Front Tires need to be off the ground just BEFORE the Rear Suspension "Tops-Out".
Both the Front AND Rear Suspensions should "Top-Out" at "almost" the same time.
The Front Suspension needs to "Top-Out" slightly BEFORE the Rear Suspension.
They must both "Top-Out" smoothly, this comes from the Rebound Settings of the Shocks.
If they don't "Top-Out" smoothly, the entire Car will try to jump off of the ground,
and you will instantly blow-away the Tires..
Preferably, the "effective" Spring-Rates of your front and rear springs,
AND the amount of suspension travel,
will be equal for both the Front AND Rear Suspensions.
Normal Ride Height should provide approximately
25% Compression Travel, and 75% Rebound Travel from "normal" ride height.
On a Drag-Only car, you may want to go even less, to ~20% / ~80%.
Softer Spring-Rates will allow for the "possibility" of a less violent initial "Hit" to the tires,
AND will extend the time and distance created by a softer "Hit".
Higher Spring Rates make everything much more critical, and harder to tune.
More Suspension Travel is almost always better.
The Suspension should NEVER "Bottom-Out" , for any reason,
if it does, increase Compression-Damping until it doesn't.
This will also reduce potential parts breakage.
Shocks are your best friend.
Never-Ever scrimp on Shocks.
Get the very best that you can afford.
The Shocks are what keeps everything under control.
A harder, more violent "Hit" may actually cause
a LOSS of Traction by "Crushing" the Tires too hard and too fast.
An extremely violent "Hit" can put more than 3-TIMES the weight of the Car on to the Rear Tires.
If you "Blow-Away" the Tires BEFORE the Front Tires are off the ground,
you're probably doing something wrong with Suspension Set-up.
If you "Blow-Away" the Tires AFTER the Front Tires are off the Ground,
you must reduce power for Track Conditions, OR, find a way to get more Traction ....
( Tire Compound, Tire Pressure, Tire Size, Rim-Width, Burn-Out procedure, etc. )
( You may also be "Topping-Out" the Rear Shocks )
A Side-View Video of the Car leaving the Line is your most valuable Tuning-Tool,
along with an extensive Data-Acquisition-System.
The Car should rise EVENLY, FRONT AND REAR, for as much Distance / Time as possible.
.
.
.
Jim Brown thanks so much for your comments! Thank-you for taking the time to write all this in the comment. Go fast, go straight! Be Safe!!