Coming from an 05 wrx to a 12 wrx I was pretty disappointed the first time I got stuck on the side of a ski mountain because I had a check engine light and I realized I had an open diff and no traction control. Coming from the 05 wrx which was a tank in the snow. Was even more disappointed at my first rallyx event when I could tell the open diff was holding me back. For someone who wants to keep his car under 350whp (currently stock with 192k original miles) I've been trying to figure out whether a 6 speed swap is better for me than a Cusco lsd. So this information is great since it's hard to find unbiased opinions. Thanks guys keep up the great videos!
Thanks for your question Joseph. If you just want to put in a rear differential, I'd say that a Quaife or AP Suretrack torque biasing diff would be a good option. It will work well with the traction control your car has, and for the street, it will get your car feeling more like the AWD platform that you are used to. But if it is in your budget, putting in a 6-speed with a front TBD and the DCCD center diff, it makes a huge difference. That is what we did with our race car (using the R180 with a TBD to go with the transmission), and it is a really big improvement. Hope that helps, thanks for watching, and Stay Tuned!
LSD’s are one of the best reasons for a 6MT upgrade. I just replaced a 5MT and decided to add a Quaife QDH3Y to the new one. It was a rewarding job to do but the cost to also add non viscous center and rear LSD’s gets you within spitting distance of a used 6MT, which has the added benefit of more durability and an extra gear. Keep the great videos coming!
Thanks Cody! Yeah, I ended up rebuilding my 5-Speed about 6 months before we figured out our 6-Speed swap. I put in all new gears and a Modena front TBD. It makes a huge difference for sure. The only think I miss is the DCCD. Someday maybe... Thanks for watching and Stay Tuned!
Thoughts on the R160 suretrac diffs? Im seriously debating on a clutch type or a torsen (suretrac) Im debating because this is going to be in my daily and i want it to be fun, reliable, always work, and have the same maintenance intervals as stock. Im not tracking this car, it will at most see an autocross session every month or so (probably even less). However, it will see alot of fun skids in the snow, rain, gravel, dry pavement, etc. So what would be the proper approach to adding a rear LSD to an R160 on my (2016) WRX? (i just want this thing to get sideways in a fun controlled manner, the open diffs dont cut it when trying to do so)
Thanks for watching and thanks for your question. I'd say given your parameters, you would be very happy with a Torque Biasing Differential, or Suretrac. They have great manners on the street and there aren't any chances to maintenance, etc. They work well in the snow, too. If you get to the point where you are breaking traction on tarmac more (which it doesn't sound like you would be necessarily, that is where the plated diff would come into play. Hope that helps and Stay Tuned!
@@FlatironsTuning Great! And thank you for the proper response. When I ask this question in the Subaru community I usually get a snarky answer of "why do you need that, just enjoy the car as is" or "what you're doing is reckless and you should take it to the TRACK" or "why didn't you buy RWD" Anyways, I look forward to your next video and what you guys do next for your business in general. Im happy there's still people like you in the Subaru community.
I have a r160 rear differential from a 2011-2014 wrx. I find torque biasing differential options to be lacking. Most people say to just to go for the Cusco 1.5 way lsd. I use my car mostly for auto cross and light track days 1-3 times a year. So it’s a street car. Do you have any recommendations ?
Thanks for your question. If you just want to make some improvement, but are trying to avoid going into the transmission, a torque biasing diff in the rear would be a nice improvement, and works great on the street. I'd look at Quaife, or for an AP Suretrack diff for you R160. If you are considering going into the transmission as well, and you can fit it in the budget, a full 6-speed swap with the front TBD, and center DCCD will make a huge difference. Hope that helps and Stay Tuned!
@@FlatironsTuning thank you! I’ll look into those. Yes, I’m just looking for a small improvement to make my car more fun to drive but I don’t want all the hassle with clutch base diffs locking up all the time in parking lots, and the maintenance on them. Just trying to keep it simple.
So what about maintenance on switching to a clutch type diff? How often would a bolt on street driven Sti need to be rebuilding a clutch type diff and what kind of cost are you looking at?
That is a good question. We have run a Cusco rear differential in our Rally car for a long time, and it has only been rebuilt once. And even then, Cusco said that overall the clutch disk's looked good. More than likely, as long as you are using a good rear diff fluid, you will just need to change the fluid every 15,000 or 30,000 miles, and that is about it. One of the reason that we like the Cusco diff's in our rally car is because they are so durable. Hope that helps and Stay Tuned!
With a rear 1.5 way. What sort of locking percentage do you recommend. My car is intended to be built for asphalt rally sprints. Is 100% to much out of the box? Also, whats your opinion of Kaaz vs cusco?
Thanks for your question. Have you watched this video where we go into how clutch type differentials work: th-cam.com/video/pf-s0f2EL2g/w-d-xo.htmlsi=gKVNfS89_7N9D56e That would be a good starting point. For an OE diff, the challenge is going to be finding parts. There was a Group-N re-build kit for those diff's but I am not sure if it is available any longer. If not, the best next step would be to move to something like the Cusco so you have parts available to make changes as you see fit. Hope that helps and Stay Tuned!
Thanks for your question. From our experience the TC/VDC is okay with the mechanical diff because the wheel speed delta is usually less. But on track I'd say you would want to turn it off to make sure that it doesn't interfere in an odd way with the handling of the car. Thanks for watching and Stay Tuned!
I have a question about the clutches in the 02-05 wrx rear VLSD. You shown a picture of the disc stacking. What is the end results for each 100-80-60% stacking? I bought a used diff from a 02 wrx and I went to drive it about 3 miles down the road it started getting noisy and binding until the passenger tire slowed me down and eventually was skidding on wet roads. It freed up when I reversed and was okay for about a mile. I removed the diff and all the gears are fine, I'm in the process of deciding to clean and restack the clutch disc's and check specs. What grease is used for the disc's? I came across an unsure answer of 100000cst silicon.. Am I wasting my time or have you experienced anything like this?
*is the disc stacking outer/inner only pattern for stock and I've also heard of the shims but I am wondering if I have to remove a few discs because of the binding issue
Thanks for your question. That is only for the aftermarket clutch type LSD's not the factory VLSD's. In those, the fluid in the sealed diff is what gives you the locking. I would say that you may be able to rebuild the rear diff, but that isn't something that we have done, so I can't speak from experience. Best of luck and Stay Tuned!
What are the options for an aftermarket LSD upgrade for the front and center diff for a VA WRX? I read that the VA STi OEM helical front diff will fit the VA wrx and also read there were options for the center diff that bias more power to the rear for past generations the WRX but not sure about the VA chassis. Thanks!
Thanks for your question. As far as I know there are not too many differential options for the split-case 6-speed trans. There is a stronger viscus center differential (12kg and 20kg). Those will keep the torque split closer to 50/50. I would doubt that the STI front diff will fit the WRX split case trans, but we may look into it. Thanks for watching and Stay Tuned!
Correct, all of Cusco's differentials are clutch type, so LSD. If you can find one, another good torque biasing option is the AP Suretrack. Thanks for watching and Stay Tuned!
What would be the best rear lsd for a rallycross wrx that also get driven on the highway? Dirt, gravel, sand, mud, snow, but also dd-able? Torsen/helical?
Thanks for your question. That is a tough one. For a daily drivable diff, the torque biasing diffs tend to be more civilized. The problem is that for slick conditions like gravel, sand, mud, etc., they really end up not being that effective. I'd say that if you really want a differential that makes a difference in those conditions, you would want a clutch type diff like a Cusco. You can certainly drive those on the street, it will just make a bit of noise, but it should last a good while. Hope that helps and Stay Tuned!
Thanks for your question. Since you have an R160 rear differential, I think that you should be able to find something from Quaife, or maybe an older AP Suretrac (from a Subaru that came with that differential). Those are the main options that come to mind. Hope that helps and Stay Tuned!
@@FlatironsTuning Thanks so much for the advice definitely looking into the Quaife rear! I'm think this is best because my car is only pushing a bit higher than stock (~300hp) and the car is mostly daily driven but used on a few HPDE events and autocross per year. Do you think the ATB would smoother in operation than a clutch type like a cusco? I've also heard lots of drivers of the VA chassis say the 1.5 cusco help reduced understeer and feel more like a RWD car, do you think the ATB type rear LSD give me a similar effect?
@@FlatironsTuning I installed an quife atb LSD on my 2016 VA WRX and it works beautifully! the car feels more like a RWD car in some situations now. thanks guys, this should've been an option from subaru imo like they have on the GR corolla.
Thanks for your question. Motul Gear 300 or Subaru High Performance MT Fluid are both good starting points. If or when you put in a clutch type differential, the diff manufacturers typically have recommended fluids. Motul Gear 300 LS has worked well, and Cusco has a specific fluid for both a rear differential or a transmission with their diff in it. Motul also has Gear Competition fluid which is a 75w-140 for higher temps, or where a higher weight is needed. Thanks for watching and Stay Tuned!
Thanks for your question. I'd say that for a lot of applications, the torsen is going to work just fine. They are great on the street, and even for some extra power at the track, they work pretty well. If you get to the point where you are making over 400 whp, or you are starting to see slipping issues in the corners (especially if you are lifting a wheel, front or rear), that is where the torsen will start to be a bit limiting. For a car that sees a lot of street time, I'd say stick with the torsen until you become limited by it. Hope that helps and Stay Tuned!
Thanks for your question. The first question I would ask is are there any issues with the stock drivetrain that you would like to improve? The STI drivetrain starts off at a pretty high level, so it may not need much of a change. Maybe just a rear differential? When you are ready to get something going, open up a live chat with us and we'll be able to put something together for you.
So I want to use my 07 WRX for autocross and maybe track days if it comes down to it. So I decided that I want to swap the gear set up in the gearbox. Which means if I can I would want to put in a different front diff, center, and rear. Doing research and getting mixed answers so would anyone have any recommendations to look into?
Thanks for your question. Track and Autocross will generally demand different setups. I'd recommend narrowing down which one of those two you want to focus on, and then build the car around that. We had a really good conversation with RCE about Autocross, and I'd recommend giving it a listen: th-cam.com/video/NstPX5yCu7A/w-d-xo.html Thanks for watching and Stay Tuned!
Thanks for your question. Here is the Cusco rear differential on our site: www.flatironstuning.com/cusco-limited-slip-differential-type-rs The differential itself is $1260.00 then you just need the R180. If you have to source that as well, it could be close to the $3,000 - $3,500 range for the diff, R180, and the labor. It just depends on what you want to do. Hope that helps and Stay Tuned!
Coming from an 05 wrx to a 12 wrx I was pretty disappointed the first time I got stuck on the side of a ski mountain because I had a check engine light and I realized I had an open diff and no traction control. Coming from the 05 wrx which was a tank in the snow. Was even more disappointed at my first rallyx event when I could tell the open diff was holding me back. For someone who wants to keep his car under 350whp (currently stock with 192k original miles) I've been trying to figure out whether a 6 speed swap is better for me than a Cusco lsd. So this information is great since it's hard to find unbiased opinions. Thanks guys keep up the great videos!
Thanks for your question Joseph. If you just want to put in a rear differential, I'd say that a Quaife or AP Suretrack torque biasing diff would be a good option. It will work well with the traction control your car has, and for the street, it will get your car feeling more like the AWD platform that you are used to.
But if it is in your budget, putting in a 6-speed with a front TBD and the DCCD center diff, it makes a huge difference. That is what we did with our race car (using the R180 with a TBD to go with the transmission), and it is a really big improvement.
Hope that helps, thanks for watching, and Stay Tuned!
LSD’s are one of the best reasons for a 6MT upgrade. I just replaced a 5MT and decided to add a Quaife QDH3Y to the new one. It was a rewarding job to do but the cost to also add non viscous center and rear LSD’s gets you within spitting distance of a used 6MT, which has the added benefit of more durability and an extra gear.
Keep the great videos coming!
Thanks Cody! Yeah, I ended up rebuilding my 5-Speed about 6 months before we figured out our 6-Speed swap. I put in all new gears and a Modena front TBD. It makes a huge difference for sure.
The only think I miss is the DCCD. Someday maybe...
Thanks for watching and Stay Tuned!
You guys are seriously underrated, I've been learning a ton
Awesome info on diffs, very simple to understand, thank you!
Glad that the video helped and thanks for watching.
Stay Tuned!
Man I could talk nerdy with you all day 😂
Ha! Man, all we do around here is have nerdy conversations.
Thanks for watching and Stay Tuned!
I have an 85 rx turbo with the 3.77 viscous lsd and swapped a 4.44 ring and pinion gear set to match my trans
As always, great content.
Thanks very much! Glad that the video was helpful.
Thanks for watching and Stay Tuned!
Thoughts on the R160 suretrac diffs?
Im seriously debating on a clutch type or a torsen (suretrac)
Im debating because this is going to be in my daily and i want it to be fun, reliable, always work, and have the same maintenance intervals as stock.
Im not tracking this car, it will at most see an autocross session every month or so (probably even less). However, it will see alot of fun skids in the snow, rain, gravel, dry pavement, etc.
So what would be the proper approach to adding a rear LSD to an R160 on my (2016) WRX?
(i just want this thing to get sideways in a fun controlled manner, the open diffs dont cut it when trying to do so)
Thanks for watching and thanks for your question. I'd say given your parameters, you would be very happy with a Torque Biasing Differential, or Suretrac. They have great manners on the street and there aren't any chances to maintenance, etc.
They work well in the snow, too.
If you get to the point where you are breaking traction on tarmac more (which it doesn't sound like you would be necessarily, that is where the plated diff would come into play.
Hope that helps and Stay Tuned!
@@FlatironsTuning Great! And thank you for the proper response. When I ask this question in the Subaru community I usually get a snarky answer of
"why do you need that, just enjoy the car as is"
or
"what you're doing is reckless and you should take it to the TRACK"
or
"why didn't you buy RWD"
Anyways, I look forward to your next video and what you guys do next for your business in general. Im happy there's still people like you in the Subaru community.
I have a r160 rear differential from a 2011-2014 wrx. I find torque biasing differential options to be lacking. Most people say to just to go for the Cusco 1.5 way lsd. I use my car mostly for auto cross and light track days 1-3 times a year. So it’s a street car. Do you have any recommendations ?
Thanks for your question. If you just want to make some improvement, but are trying to avoid going into the transmission, a torque biasing diff in the rear would be a nice improvement, and works great on the street. I'd look at Quaife, or for an AP Suretrack diff for you R160.
If you are considering going into the transmission as well, and you can fit it in the budget, a full 6-speed swap with the front TBD, and center DCCD will make a huge difference.
Hope that helps and Stay Tuned!
@@FlatironsTuning thank you! I’ll look into those. Yes, I’m just looking for a small improvement to make my car more fun to drive but I don’t want all the hassle with clutch base diffs locking up all the time in parking lots, and the maintenance on them. Just trying to keep it simple.
Wouldn't electronic be the best? Work similar to ayc in the evos and reduce potential understeer.
So what about maintenance on switching to a clutch type diff? How often would a bolt on street driven Sti need to be rebuilding a clutch type diff and what kind of cost are you looking at?
That is a good question. We have run a Cusco rear differential in our Rally car for a long time, and it has only been rebuilt once. And even then, Cusco said that overall the clutch disk's looked good. More than likely, as long as you are using a good rear diff fluid, you will just need to change the fluid every 15,000 or 30,000 miles, and that is about it.
One of the reason that we like the Cusco diff's in our rally car is because they are so durable.
Hope that helps and Stay Tuned!
Awesome video!
Thanks Eric! Glad you liked it.
Thanks for watching and Stay Tuned!
Good street and canyon set up please on diff specs
With a rear 1.5 way. What sort of locking percentage do you recommend. My car is intended to be built for asphalt rally sprints. Is 100% to much out of the box? Also, whats your opinion of Kaaz vs cusco?
are there any upgrades for the 2012-2014 impreza 2.0i with FB20?
Do you have or can you make a video on how to tune (clutch stacking & preload, if possible the oem 04-06 mechanical type lsds?
Thanks for your question. Have you watched this video where we go into how clutch type differentials work:
th-cam.com/video/pf-s0f2EL2g/w-d-xo.htmlsi=gKVNfS89_7N9D56e
That would be a good starting point.
For an OE diff, the challenge is going to be finding parts. There was a Group-N re-build kit for those diff's but I am not sure if it is available any longer.
If not, the best next step would be to move to something like the Cusco so you have parts available to make changes as you see fit.
Hope that helps and Stay Tuned!
Clutch pack differential is the only way to go, anything else is dangerous especially at the rear.
They all have their place, but for competition use, the clutch type diff is definitely the way to go.
Thanks for watching and Stay Tuned!
How do the computers of Subaru adapt to the mechanical change in differential? TC, VDC, and ATV.
Thanks for your question. From our experience the TC/VDC is okay with the mechanical diff because the wheel speed delta is usually less. But on track I'd say you would want to turn it off to make sure that it doesn't interfere in an odd way with the handling of the car.
Thanks for watching and Stay Tuned!
I have a question about the clutches in the 02-05 wrx rear VLSD. You shown a picture of the disc stacking. What is the end results for each 100-80-60% stacking?
I bought a used diff from a 02 wrx and I went to drive it about 3 miles down the road it started getting noisy and binding until the passenger tire slowed me down and eventually was skidding on wet roads. It freed up when I reversed and was okay for about a mile.
I removed the diff and all the gears are fine, I'm in the process of deciding to clean and restack the clutch disc's and check specs. What grease is used for the disc's? I came across an unsure answer of 100000cst silicon..
Am I wasting my time or have you experienced anything like this?
*is the disc stacking outer/inner only pattern for stock and I've also heard of the shims but I am wondering if I have to remove a few discs because of the binding issue
Thanks for your question. That is only for the aftermarket clutch type LSD's not the factory VLSD's. In those, the fluid in the sealed diff is what gives you the locking.
I would say that you may be able to rebuild the rear diff, but that isn't something that we have done, so I can't speak from experience.
Best of luck and Stay Tuned!
What are the options for an aftermarket LSD upgrade for the front and center diff for a VA WRX? I read that the VA STi OEM helical front diff will fit the VA wrx and also read there were options for the center diff that bias more power to the rear for past generations the WRX but not sure about the VA chassis. Thanks!
Thanks for your question. As far as I know there are not too many differential options for the split-case 6-speed trans. There is a stronger viscus center differential (12kg and 20kg). Those will keep the torque split closer to 50/50.
I would doubt that the STI front diff will fit the WRX split case trans, but we may look into it.
Thanks for watching and Stay Tuned!
Torque biasing i.e. Torsen and Quaife or clutch type....Cusco are all regarded as LSD.
Correct, all of Cusco's differentials are clutch type, so LSD. If you can find one, another good torque biasing option is the AP Suretrack.
Thanks for watching and Stay Tuned!
What would be the best rear lsd for a rallycross wrx that also get driven on the highway?
Dirt, gravel, sand, mud, snow, but also dd-able?
Torsen/helical?
Thanks for your question. That is a tough one. For a daily drivable diff, the torque biasing diffs tend to be more civilized. The problem is that for slick conditions like gravel, sand, mud, etc., they really end up not being that effective.
I'd say that if you really want a differential that makes a difference in those conditions, you would want a clutch type diff like a Cusco. You can certainly drive those on the street, it will just make a bit of noise, but it should last a good while.
Hope that helps and Stay Tuned!
is there is package to out there to install a torque biasing or torsen rear diff on the VA WRX?
Thanks for your question. Since you have an R160 rear differential, I think that you should be able to find something from Quaife, or maybe an older AP Suretrac (from a Subaru that came with that differential).
Those are the main options that come to mind.
Hope that helps and Stay Tuned!
@@FlatironsTuning Thanks so much for the advice definitely looking into the Quaife rear! I'm think this is best because my car is only pushing a bit higher than stock (~300hp) and the car is mostly daily driven but used on a few HPDE events and autocross per year. Do you think the ATB would smoother in operation than a clutch type like a cusco? I've also heard lots of drivers of the VA chassis say the 1.5 cusco help reduced understeer and feel more like a RWD car, do you think the ATB type rear LSD give me a similar effect?
@@FlatironsTuning I installed an quife atb LSD on my 2016 VA WRX and it works beautifully! the car feels more like a RWD car in some situations now. thanks guys, this should've been an option from subaru imo like they have on the GR corolla.
Trans and diff gear oil preferences for different applications?
Thanks for your question. Motul Gear 300 or Subaru High Performance MT Fluid are both good starting points.
If or when you put in a clutch type differential, the diff manufacturers typically have recommended fluids.
Motul Gear 300 LS has worked well, and Cusco has a specific fluid for both a rear differential or a transmission with their diff in it.
Motul also has Gear Competition fluid which is a 75w-140 for higher temps, or where a higher weight is needed.
Thanks for watching and Stay Tuned!
Which dif would work better on a weekend warrior sti a torsen LSD or plated LSD
Thanks for your question. I'd say that for a lot of applications, the torsen is going to work just fine. They are great on the street, and even for some extra power at the track, they work pretty well.
If you get to the point where you are making over 400 whp, or you are starting to see slipping issues in the corners (especially if you are lifting a wheel, front or rear), that is where the torsen will start to be a bit limiting.
For a car that sees a lot of street time, I'd say stick with the torsen until you become limited by it.
Hope that helps and Stay Tuned!
Y'all think I could shove an old OEM LSD into a 2015+ WRX? As long as it's from an R160?
What would you recommend for a VA 2020 STI that’s a mild track car and auto cross?
Thanks for your question. The first question I would ask is are there any issues with the stock drivetrain that you would like to improve? The STI drivetrain starts off at a pretty high level, so it may not need much of a change.
Maybe just a rear differential?
When you are ready to get something going, open up a live chat with us and we'll be able to put something together for you.
So I want to use my 07 WRX for autocross and maybe track days if it comes down to it. So I decided that I want to swap the gear set up in the gearbox. Which means if I can I would want to put in a different front diff, center, and rear. Doing research and getting mixed answers so would anyone have any recommendations to look into?
Thanks for your question. Track and Autocross will generally demand different setups. I'd recommend narrowing down which one of those two you want to focus on, and then build the car around that.
We had a really good conversation with RCE about Autocross, and I'd recommend giving it a listen:
th-cam.com/video/NstPX5yCu7A/w-d-xo.html
Thanks for watching and Stay Tuned!
Any recommendations for an 05 sti from center diff. I can’t find anything. Need help
would you happen to know a ballpark price for a fully cusco built 07 sti 6MT?
Thanks for your question. Here is the Cusco rear differential on our site:
www.flatironstuning.com/cusco-limited-slip-differential-type-rs
The differential itself is $1260.00 then you just need the R180. If you have to source that as well, it could be close to the $3,000 - $3,500 range for the diff, R180, and the labor. It just depends on what you want to do.
Hope that helps and Stay Tuned!
Wouldn’t want homie on left to thne anything 👀 😂😂
04-06 R180 + racingdiffs plates = 100ft-lb of lock for a bargain.
Thanks for watching. Stay Tuned!
Great video!!
Thanks very much. Stay Tuned!