I want to put coilovers on my '73 AMC Javelin. The original front spring has a free height of 14.31 inches and a spring rate of 307 lbs. If I purchase a coil-over that is 10" long, should choose the same spring rate as the original (assuming I want the car to ride as before) or do I need to select a different rate since the coil-over is shorter?
I have a 1929 model a. My front springs are nearly completely compressed when sitting. It has a stock 302 engine. Any idea what weight front suspension springs you'd recommend?
If you're trying to limit suspension travel to limit most suspension movement, you would need a higher spring rate, especially with a stanced setup. You could also use a bump stop to limit your travel.
I think this how you calculate unsprung spring rate or what spring you need. So if your rear end was 1500 pounds and you subtract tires, axle, brakes, etc and you end up with 1200 pounds, your spring should be able support that weight without bottoming out. So if you take 1200 and devide by 4 you'll get 300 So you need a spring with a rate of 300 or a longer spring. This would be 25% compression for a 16 inch spring. 450 pounds in the example seems like a small amount, unless he was referring to a small car?
Hi thanks for the information want to ask a question I have a machine of 150kg weight and i'm wondering which spring do I need for it how can I make the calculation ?
It a bit of work but you can weigh your axle by - jack up the car Put weigh scale under each wheel. Disconnect the shocks so wheels are sitting on the scales. Read off the weights. Suspension arms at mid travel give the closest figure.
I’m trying to get some coil overs but I have a couple of mods I have a 81 Malibu with 3 inch lift spindle top a arm has a 1 inch drop I have your bottom a arms no drop just trying to get a coilovers that are inter or do I just need a bigger coil
Hi there! Since you have a little bit of a custom setup, I would recommend calling and speaking with our tech team! They will be able to recommend the right setup for you! 952-985-5675 and we are open M-F 8am-5pm CST. Thanks!
I'm wondering, given that I find a theoretical optimal spring rate for comfort, how would I go about making sure it can take the forces from bumps? Is this taken up by the damper?
general car> setup 25-35% of the wt on each corner would b idle. Cars r front wheel drive & front engine so yeah all up front not race car mid engine idle, & diff then a 4 by 4 set up. Is front axle solid or IFS is back solid or IRS how much travel is factor in how much wt u want to put on it + if truck the rear is going to see most of added wt or ppl wt 2 door front will gain etc.
Typically yes, depending on the application. You need a higher spring rate to support all the weight of the front of the car. Give us a call and we will be happy to recommend something for you!
@@QA1TECH I think SUVs have higher rates in the rear because they are expected to handle some hauling and also when they aren't, it helps prevent excessive understeer. I also see FWD cars when setting up for handling run higher rates in the rear for the same reason. Is that what you guys see?
I have suzuki dzire 2017 in India. I find the suspension to be stiff. As i am suffering from back pain, i want soft suspension, how can i make my suspension a little softer...plz help
Hi there! We, unfortunately, do not catalog anything for Suzuki. I am not sure how much adjustability is allowed on the factory suspension that your Suzuki has, so we recommend looking at aftermarket suspension components to help with getting your ride softer.
BC Racing Coliovers are 6k Front, and 5k Rear, I think that's too soft for my car since I plan on lowering my car to a 2.8 inch Drop in the Front, and a 2.6 inch in the Rear, they do customized the Spring rates for you, but the question is I don't know how much each corner weights. I might just take the Spring rates they offer 6k and 5k and call it a day, I don't want to go too high on the Spring rate only to make my car ride like crap, or I might do 8k for the Front, and 6k for the Rear. This is confusing.
Right! and not once did he mention 6k-8k-10k etc.... i have an Evo 8 and dont really know what a higher spring rate is going to do for me. Megans "Street" series come with 8kg Front and 6kg Rear, and their "Track" series are 12kg Front and 10kg Rear i Think i need 10kg Front & 8kg rear which is right in the middle of the 2 But Yes...Very Confusing when its not being explained right
@@Thr33.Sid3z the higher the rate, the worse the ride on the street/better the handling on the track. Like let's say 14k front, 14k rear will not be good in street driving and your car could leave the ground if you run over bumps too quickly and you'll lose control. On the track however, you'll be dominating other cars. A 5k front and 5k rear will be a smooth ride and you won't run the risk of losing control over bumps. You will however, realize really quickly that they are way too soft on a track. People usually try to stick between 8k-11k for both front and rear if they are street driven and track driven. Also, pay very close attention to valving because that will HAVE A LOT TO DO WITH THE RIDE QUALITY along with the spring rates
You plan on slamming your car on an aggressive setup I'd suggest a high spring rate 8k or more I have 8k front 6k rear and about 1 inch and 1/2 drop and I rub like crazy in the rear when going over bumps with weight in the back and I still have wheel gap So if you want a minimal wheel gap and be static I'd go with at least 10k or more
I just bought BC Racing Coliovers Extreme Drop I'm running 12kg Fronts 2.7 inch Dropped and 6kg Rears 2.5 inch Dropped custom Spring rates basically I'm running an aggressive Ride Height about an inch and a half from the ground to my Front lip but the Rears sit higher up for clearance since the Rears usually face the most impact you will feel it bottom out if it's too low to the ground
comment 51:must see/hear video: not just how much wt per corner but more important spring weighing method how much wt on this spring on this corner current setup as far as what is on in the car & how it is sitting. Kind of the same thing but truer in a way number, & it's not a fixed number, bc like a trailer raise or lower hitch & wt is diff.
I'm confused about something. He says that you always want 25 - 30% of the spring compressed. So if that's an 11 inch spring, that's 2.75 - 3.30 inches. However he also says that you can tell how much weight is on a spring from the car, by how much the spring compresses. What I don't understand is what that knowledge actually gives you? Seeing as you must have a certain amount of the spring compressed, seems you are limited by what actual weight of spring you need, because any stiffer than what the car already weighs on it and it won't compress at least 25%, and any softer and it will compress more than 30%. How would you use this knowledge when selecting race car springs when you are actively TRYING to make a car more stiffer? Because the weight of the car is a constant. Seems to me you would get to a point where the stiffer a spring you install, the less it will obviously compress? Which is bad? But isn't that the point of a stiffer spring?
Hi Don, good question, and we see what you're saying. In a race car scenario, when you're using the spring as a tuning device for controlling load on the suspension, you may operate outside of this range. The 25-30% is more of a general rule of thumb or starting point for selecting an initial spring rate. Depending on the application and use of the vehicle, you may decide to use a stiffer or softer spring. Thanks!
Firstly, I'm no expert. However, I believe if you have two spring rates to choose from, one soft and the other stiff, then the softer spring would need to be longer in free length than the stiffer spring. Therefore you could have the same percentage compression of the springs with the cars load on them. This could be done in such a way as to not effect ride height despite one spring being shorter because it compresses less than the longer spring. This also prevents losing shock travel when choosing a softer spring. Hope someone else can explain further
I'm confused. he raid "if it comes down 11inches" (are they refering to the ride height?) and then he followed that by saying "that means the spring is compressing 3 inches" ?? how? what? please can some explain
Hi Billy, He's explaining that if you measure this spring (which has a 14 inch free length) while it's installed, and it measures 11 inches, it's 3 inches shorter than with no weight on it. Since the spring rate is 150 lbs per inch, and the weight of the car is compressing the spring 3 inches, you know there is approximately 450 lbs of force acting on the spring. Hope this helps, let me know if you have more questions. Or you can call our tech line (952-985-5675) if you have more technical questions on your particular application.
You need some preload to prevent the spring from moving around when the shock is at its full length. Adjusting the amount of preload can give you some desirable handling characteristic depending on the application.
The spring rate is based on the front end weight of the vehicle. If the car has torsion bars it doesn’t need coil-over springs since it already has springs supporting the weight of the car.
@@sam198130 Then we would recommend a 500 lb spring for the front. We have front pro coil systems that include the shock and spring. For example, if you wanted a single adjustable coil-over shock, the part number would be GS507-10500C.
14” spring length x 150lbs/inch of compression = 2100lbs to fully compress that spring!!! No!!! I’m positive that that spring is not rated for 2100lbs. The amount of weight it takes to compress a spring one inch is for the first inch and progressively takes more weight as the spring compresses. Springs do not compress linearly as he suggested.
I want to put coilovers on my '73 AMC Javelin. The original front spring has a free height of 14.31 inches and a spring rate of 307 lbs. If I purchase a coil-over that is 10" long, should choose the same spring rate as the original (assuming I want the car to ride as before) or do I need to select a different rate since the coil-over is shorter?
I would recommend calling into our tech line to see what the best setup would be. 952-985-5675
I have a 1929 model a. My front springs are nearly completely compressed when sitting. It has a stock 302 engine. Any idea what weight front suspension springs you'd recommend?
Hi I got a question before I purchase which is the most popular coil over front and back the 350, 450, 550, 650?
depends on weight of the car too well according to Honda tech
What can I weigh each corner of a c-10?
What would I need for a 68 C10? Ls3 engine, I need front and rear. Oh and what do you recommend, single or double adjustability?
If the truck is mainly a street truck, the single adjustable option would be a good one! And we would recommend a 750 lb. spring rate.
@@QA1TECH and for the rear? Single adjustability with what spring rate do you think?
@@tonyhuerta3088 Same adjustability, but you would want a 200 lb. spring rate.
So my stance car weights fuck all so I should run 600 rate 5 inch springs so I don't ground out or rub arch?
If you're trying to limit suspension travel to limit most suspension movement, you would need a higher spring rate, especially with a stanced setup. You could also use a bump stop to limit your travel.
Hey can you give me any idea about how much( in percent) spring should compress under a car's weight if its an ATV
Depending on ride height, but you’d like 2” of minimum compression on both end or they will bottom/ top out
10-35%. Depends on preference. I dont like to much on my front of my race atv
I think this how you calculate unsprung spring rate or what spring you need.
So if your rear end was 1500 pounds and you subtract tires, axle, brakes, etc and you end up with 1200 pounds,
your spring should be able support that weight without bottoming out.
So if you take 1200 and devide by 4 you'll get 300
So you need a spring with a rate of 300 or a longer spring. This would be 25% compression for a 16 inch spring.
450 pounds in the example seems like a small amount, unless he was referring to a small car?
Jeep wrangler JK 2013 whats the 2.5” coil spring rate front and rear please ?
Hi thanks for the information
want to ask a question
I have a machine of 150kg weight and i'm wondering which spring do I need for it
how can I make the calculation ?
What do you mean softer spring rate? Higher or lower number weight to compress 1 inch?
well done, very clear and informative. Thank you
You bet! Glad you found this video helpful!
2018 shaw dirt late model 3 tenths low bank stop and go slick dirt track what rf spring do i need? Corner weight is 500lbs
What would you suggest for rear double adjustable coilovers for a 1996 impala ss?
Hi there! Depending on what you are looking to do with the vehicle, we typically recommend our medium spring rate of 200 lbs. Part number RCK52380
It a bit of work but you can weigh your axle by -
jack up the car
Put weigh scale under each wheel.
Disconnect the shocks so wheels are sitting on the scales.
Read off the weights. Suspension arms at mid travel give the closest figure.
What kind of scale?
What spring rate in the rear for a 70 c10 short bed with a 6.0 ls.? It will be a street truck but want it to hook
What spring rate worked for you?
I’m trying to get some coil overs but I have a couple of mods I have a 81 Malibu with 3 inch lift spindle top a arm has a 1 inch drop I have your bottom a arms no drop just trying to get a coilovers that are inter or do I just need a bigger coil
Hi there! Since you have a little bit of a custom setup, I would recommend calling and speaking with our tech team! They will be able to recommend the right setup for you! 952-985-5675 and we are open M-F 8am-5pm CST. Thanks!
I'm wondering, given that I find a theoretical optimal spring rate for comfort, how would I go about making sure it can take the forces from bumps? Is this taken up by the damper?
The spring supports the weight of the vehicle while the damper controls the ride quality, thanks!
Hello
I have 2012 Hyundai Sonarta GLS 2.4. What spring rating should i go for?
Pleae let me know i am very confused.
Thanks
Hi there! Please reach out to our tech team at 952-985-5675
general car> setup 25-35% of the wt on each corner would b idle. Cars r front wheel drive & front engine so yeah all up front not race car mid engine idle, & diff then a 4 by 4 set up. Is front axle solid or IFS is back solid or IRS how much travel is factor in how much wt u want to put on it + if truck the rear is going to see most of added wt or ppl wt 2 door front will gain etc.
Wow great information
300 lbs for a solid rear axle set up. How much would you estimate for a typical double wishbone front suspension?
Would u have a higher spring rate on the front end of the car vs the rear end
Typically yes, depending on the application. You need a higher spring rate to support all the weight of the front of the car. Give us a call and we will be happy to recommend something for you!
@@QA1TECH I think SUVs have higher rates in the rear because they are expected to handle some hauling and also when they aren't, it helps prevent excessive understeer. I also see FWD cars when setting up for handling run higher rates in the rear for the same reason. Is that what you guys see?
Hookes law!! F=kx, could use simulink and play with different zetas.
I have suzuki dzire 2017 in India. I find the suspension to be stiff. As i am suffering from back pain, i want soft suspension, how can i make my suspension a little softer...plz help
Hi there! We, unfortunately, do not catalog anything for Suzuki. I am not sure how much adjustability is allowed on the factory suspension that your Suzuki has, so we recommend looking at aftermarket suspension components to help with getting your ride softer.
BC Racing Coliovers are 6k Front, and 5k Rear, I think that's too soft for my car since I plan on lowering my car to a 2.8 inch Drop in the Front, and a 2.6 inch in the Rear, they do customized the Spring rates for you, but the question is I don't know how much each corner weights. I might just take the Spring rates they offer 6k and 5k and call it a day, I don't want to go too high on the Spring rate only to make my car ride like crap, or I might do 8k for the Front, and 6k for the Rear. This is confusing.
Right! and not once did he mention 6k-8k-10k etc....
i have an Evo 8 and dont really know what a higher spring rate is going to do for me.
Megans "Street" series come with 8kg Front and 6kg Rear, and their "Track" series are 12kg Front and 10kg Rear
i Think i need 10kg Front & 8kg rear which is right in the middle of the 2
But Yes...Very Confusing when its not being explained right
@@Thr33.Sid3z BC Racing usually customize the Spring rates for you 12k is probably the max for street daily use
@@Thr33.Sid3z the higher the rate, the worse the ride on the street/better the handling on the track. Like let's say 14k front, 14k rear will not be good in street driving and your car could leave the ground if you run over bumps too quickly and you'll lose control. On the track however, you'll be dominating other cars. A 5k front and 5k rear will be a smooth ride and you won't run the risk of losing control over bumps. You will however, realize really quickly that they are way too soft on a track. People usually try to stick between 8k-11k for both front and rear if they are street driven and track driven. Also, pay very close attention to valving because that will HAVE A LOT TO DO WITH THE RIDE QUALITY along with the spring rates
You plan on slamming your car on an aggressive setup I'd suggest a high spring rate 8k or more
I have 8k front 6k rear and about 1 inch and 1/2 drop and I rub like crazy in the rear when going over bumps with weight in the back and I still have wheel gap
So if you want a minimal wheel gap and be static I'd go with at least 10k or more
I just bought BC Racing Coliovers Extreme Drop I'm running 12kg Fronts 2.7 inch Dropped and 6kg Rears 2.5 inch Dropped custom Spring rates basically I'm running an aggressive Ride Height about an inch and a half from the ground to my Front lip but the Rears sit higher up for clearance since the Rears usually face the most impact you will feel it bottom out if it's too low to the ground
comment 51:must see/hear video: not just how much wt per corner but more important spring weighing method how much wt on this spring on this corner current setup as far as what is on in the car & how it is sitting. Kind of the same thing but truer in a way number, & it's not a fixed number, bc like a trailer raise or lower hitch & wt is diff.
I'm confused about something. He says that you always want 25 - 30% of the spring compressed. So if that's an 11 inch spring, that's 2.75 - 3.30 inches. However he also says that you can tell how much weight is on a spring from the car, by how much the spring compresses. What I don't understand is what that knowledge actually gives you? Seeing as you must have a certain amount of the spring compressed, seems you are limited by what actual weight of spring you need, because any stiffer than what the car already weighs on it and it won't compress at least 25%, and any softer and it will compress more than 30%. How would you use this knowledge when selecting race car springs when you are actively TRYING to make a car more stiffer? Because the weight of the car is a constant. Seems to me you would get to a point where the stiffer a spring you install, the less it will obviously compress? Which is bad? But isn't that the point of a stiffer spring?
Hi Don, good question, and we see what you're saying. In a race car scenario, when you're using the spring as a tuning device for controlling load on the suspension, you may operate outside of this range. The 25-30% is more of a general rule of thumb or starting point for selecting an initial spring rate. Depending on the application and use of the vehicle, you may decide to use a stiffer or softer spring. Thanks!
Firstly, I'm no expert. However, I believe if you have two spring rates to choose from, one soft and the other stiff, then the softer spring would need to be longer in free length than the stiffer spring. Therefore you could have the same percentage compression of the springs with the cars load on them. This could be done in such a way as to not effect ride height despite one spring being shorter because it compresses less than the longer spring. This also prevents losing shock travel when choosing a softer spring. Hope someone else can explain further
I'm confused. he raid "if it comes down 11inches" (are they refering to the ride height?) and then he followed that by saying "that means the spring is compressing 3 inches" ?? how? what? please can some explain
Hi Billy,
He's explaining that if you measure this spring (which has a 14 inch free length) while it's installed, and it measures 11 inches, it's 3 inches shorter than with no weight on it.
Since the spring rate is 150 lbs per inch, and the weight of the car is compressing the spring 3 inches, you know there is approximately 450 lbs of force acting on the spring.
Hope this helps, let me know if you have more questions. Or you can call our tech line (952-985-5675) if you have more technical questions on your particular application.
QA1 oh of course haha. all makes sense now. Thanks for the reply
One more question why would someone adjust pre load?
You need some preload to prevent the spring from moving around when the shock is at its full length. Adjusting the amount of preload can give you some desirable handling characteristic depending on the application.
Where's the starting point, how do I determine what coil over I need if my car didn't come factory with them but has torsion bars ?
The spring rate is based on the front end weight of the vehicle. If the car has torsion bars it doesn’t need coil-over springs since it already has springs supporting the weight of the car.
@@QA1TECH okay thanks, I was going to do a conversion.
@@Moparmaga-1 You can give our tech line a call and they can give you the best recommendation! 952-985-5675
I got a 96 ss impala which spring would I need
Are you looking for a spring rate for the front of your vehicle? Are you running a small or big block engine?
@@QA1TECH 1996 ss impala 5.7
@@sam198130 Then we would recommend a 500 lb spring for the front. We have front pro coil systems that include the shock and spring. For example, if you wanted a single adjustable coil-over shock, the part number would be GS507-10500C.
@@QA1TECH I want a double coil over shock whats the part number
@@sam198130 Okay, then the part number would be GD507-10500C
Ok gracias desde colombia ,
300 lbs..lol my sub box alone is 300 lbs
We offer other spring rates that are higher than 300 lbs.
14” spring length x 150lbs/inch of compression = 2100lbs to fully compress that spring!!! No!!! I’m positive that that spring is not rated for 2100lbs. The amount of weight it takes to compress a spring one inch is for the first inch and progressively takes more weight as the spring compresses. Springs do not compress linearly as he suggested.
Some springs are linear springs.
Informative but background music to loud
he looks bored
We answer a lot of spring rate questions, LOL
The boss were there.😅
What the
kill the music