[Michael__kopp]

Anyone use these? Im about to order some and just wanted to know if anyone had any thoughts on them? Were they hard to install because they are a more rigid material?

[Cloud9blue]

It's tiny bit more rigid than their yellow bushings (95A vs 75A in terms of Shore hardness rating, google that up if you don't know what that means). What bushings did you order btw?

[Michael__kopp]

I am still on the fence about ordering the subframe bushings and the diff bushings. Is it worth doing the diff bushings at the same time or just save it for a different time? I don't know how much disassembly is shared in the two jobs.

[Cloud9blue]

Originally Posted by Michael__kopp

I am still on the fence about ordering the subframe bushings and the diff bushings. Is it worth doing the diff bushings at the same time or just save it for a different time? I don't know how much disassembly is shared in the two jobs.

Depends what you are trying to achieve? Street driving only, diff probably not worth the trouble. But if you track it (especially is you drag race it), I think the diff bushings are going to be critical (more so on a manual). Since you are dropping the whole subframe anyway (diff is attached to the rear subrame), switching the diff bushing is probably just gonna one hour of extra labor for a competent tech. But if you are DIYing this, I think you can rent out the bushing tools from HPA to make your life a lot easier.

FYI, I would go with the stiffest subframe bushing you can deal with and a bit softer diff bushings for NVH reasons.

[Stucks]

Originally Posted by Cloud9blue

FYI, I would go with the stiffest subframe bushing you can deal with and a bit softer diff bushings for NVH reasons.

this.

[EJ_3]

Originally Posted by Cloud9blue

Depends what you are trying to achieve? Street driving only, diff probably not worth the trouble. But if you track it (especially is you drag race it), I think the diff bushings are going to be critical (more so on a manual). Since you are dropping the whole subframe anyway (diff is attached to the rear subrame), switching the diff bushing is probably just gonna one hour of extra labor for a competent tech. But if you are DIYing this, I think you can rent out the bushing tools from HPA to make your life a lot easier.

FYI, I would go with the stiffest subframe bushing you can deal with and a bit softer diff bushings for NVH reasons.

Originally Posted by Stucks

this.

Interesting, any polyurethane bushing replacement will perform better than stock so I can see this. I'm assuming this method is for daily/street, not performance/tracking since you're mentioning NVH? I have powerflex black sf bushings and was about to order matching diff bushings and some diff fluid since I just got my LSD. I auto-x, drag, and do road courses, but my car isn't by definition a race car (gutted, full roll cage, and aero), but it's my fun car and don't get drove daily. Should I stick with my plan or would you recommend powerflex purple diff bushings to pair with black sf bushings or yellow?

[ashmostro]

Purple on diff, black on sf will be fine for the street

[whosdady]

I have yellow subframe bushings and purple diff bushings and they are not enough for the street.

I'm very unhappy! Looking spec N and Delein...

[Cloud9blue]

Originally Posted by whosdady

I have yellow subframe bushings and purple diff bushings and they are not enough for the street.

I'm very unhappy! Looking spec N and Delein...

care to list out your supporting suspension mods and the actual issue you experience with the current setup?

everyone has different expectations and tolerance for NVH, so this sort of posts isn't exactly helpful.

[I35it]

Just get aluminum subframe inserts and some yellow diff bushings. No issues what so ever.

[cvc 22349a]

Originally Posted by whosdady

I have yellow subframe bushings and purple diff bushings and they are not enough for the street.

I'm very unhappy! Looking spec N and Delein...

Pls post your experience if you install the group n bushings

[whosdady]

Originally Posted by Cloud9blue

care to list out your supporting suspension mods and the actual issue you experience with the current setup?

everyone has different expectations and tolerance for NVH, so this sort of posts isn't exactly helpful.

This is only the 3rd or 4th time this question has come up in the last couple of months. Feel free to search. But I don't mind listing my suspension mods again.

I have all of the e92 m3 front and rear suspension mods. (Less than 6 months old) Including front strut bar.

- Olhins coilovers with swift 12g springs in the rear positioned at 15 clicks from soft.

- Megan adjustable toe links.

- OS Giken vac built lsd with forged vac cover.

- 265 Michelin pss in the rear (70% tread left) attached to oem 313 19 inch performance wheels.

- power flex yellow subframe bushings and power flex purple diff bushings. RE tranny mounts.

- car is a 6at with 54k miles with an aggressive PTF tune. FBO 50% e85.

- alignment has been done 4 times over the last year to help rectify the problem below. Wheels and tires have been switched to also try and resolve this issue.

Car will not stay in a straight line under hard acceleration. It goes perfectly straight under normal driving. However the right rear pushes out hard when I floor it. Wheels spin at 75mph if I punch it. I believe the subframe/diff are moving slightly due to the weak yellow/ purple power flex bushings. This seems to be a common problem power levels over 400rwtq.

All I'm looking for is the car to track straight under full acceleration in a straight line. Hopefully this was more helpful.

[Cloud9blue]

Originally Posted by whosdady

This is only the 3rd or 4th time this question has come up in the last couple of months. Feel free to search. But I don't mind listing my suspension mods again.

I have all of the e92 m3 front and rear suspension mods. (Less than 6 months old) Including front strut bar.

- Olhins coilovers with swift 12g springs in the rear positioned at 15 clicks from soft.

- Megan adjustable toe links.

- OS Giken vac built lsd with forged vac cover.

- 265 Michelin pss in the rear (70% tread left) attached to oem 313 19 inch performance wheels.

- power flex yellow subframe bushings and power flex purple diff bushings. RE tranny mounts.

- car is a 6at with 54k miles with an aggressive PTF tune. FBO 50% e85.

- alignment has been done 4 times over the last year to help rectify the problem below. Wheels and tires have been switched to also try and resolve this issue.

Car will not stay in a straight line under hard acceleration. It goes perfectly straight under normal driving. However the right rear pushes out hard when I floor it. Wheels spin at 75mph if I punch it. I believe the subframe/diff are moving slightly due to the weak yellow/ purple power flex bushings. This seems to be a common problem power levels over 400rwtq.

All I'm looking for is the car to track straight under full acceleration in a straight line. Hopefully this was more helpful.

that must be annoying after all those work... I have similar setup (full M3, w/ whiteline subframe bushings, wavetrac LSD), but doesn't have such problem while running Hankook R-S3 tires. However, I am probably making 20-30 less whp than you since I don't run that aggressive of ethanol mix. I would ditch the PSS, great street tires they are, but they are way overhyped as a capable track tires.

The problem with stock frame turbo is the torque comes on so quickly, you really need stickier tires or be more gradual with the throttle (get some weight transfer to the rear wheels first before going WOT).

[cvc 22349a]

Originally Posted by whosdady

This is only the 3rd or 4th time this question has come up in the last couple of months. Feel free to search. But I don't mind listing my suspension mods again.

I have all of the e92 m3 front and rear suspension mods. (Less than 6 months old) Including front strut bar.

- Olhins coilovers with swift 12g springs in the rear positioned at 15 clicks from soft.

- Megan adjustable toe links.

- OS Giken vac built lsd with forged vac cover.

- 265 Michelin pss in the rear (70% tread left) attached to oem 313 19 inch performance wheels.

- power flex yellow subframe bushings and power flex purple diff bushings. RE tranny mounts.

- car is a 6at with 54k miles with an aggressive PTF tune. FBO 50% e85.

- alignment has been done 4 times over the last year to help rectify the problem below. Wheels and tires have been switched to also try and resolve this issue.

Car will not stay in a straight line under hard acceleration. It goes perfectly straight under normal driving. However the right rear pushes out hard when I floor it. Wheels spin at 75mph if I punch it. I believe the subframe/diff are moving slightly due to the weak yellow/ purple power flex bushings. This seems to be a common problem power levels over 400rwtq.

All I'm looking for is the car to track straight under full acceleration in a straight line. Hopefully this was more helpful.

Orb told me a long time ago the primary culprit is subframe bushings. He has solid mounts iirc. If I were to do it again it'd be group n for me.

[whosdady]

Originally Posted by Cloud9blue

that must be annoying after all those work... I have similar setup (full M3, w/ whiteline subframe bushings, wavetrac LSD), but doesn't have such problem while running Hankook R-S3 tires. However, I am probably making 20-30 less whp than you since I don't run that aggressive of ethanol mix. I would ditch the PSS, great street tires they are, but they are way overhyped as a capable track tires.

The problem with stock frame turbo is the torque comes on so quickly, you really need stickier tires or be more gradual with the throttle (get some weight transfer to the rear wheels first before going WOT).

I have almost crashed twice. It is really disappointing. I can't take it to the track in fear I will enter the other lane or hit the wall.

Tires are on the list...

I haven't decided on which ones? I like the re11's and r888's. I may need to take a look at the rs3's. This is my daily driver so I do need some other needs, which is why I went with the pss. But I think you are absolutely right about them. Are there any other tires I should look at?

[Cloud9blue]

Re11 is better for street use. Hankook grips betters in dry but awful when it is cold or wet.

[JC335xi]

I ran the RE-11a this last summer for mixed DD/Auto-x use and was nothing but pleased with the performance.

[ashmostro]

If you are looking at extreme summers you should also consider yoko ad08/ad08r

[whosdady]

How do the RE-11a's compare to the standard RE-11's?

I wish I could have 4 sets of wheels/tires. I've been researching tires a lot over the last few days and have come to this conclusion...

The M PSS are a great all around tire that do really well in wet, cold and dry weather when new and with less than 450rwhp. One of the greatest benefits is how light weight they are compared to the other sticky wheels. Not to mention, the tread lasts a long time.

Unfortunately I can't keep my car in as trainer line and would like even more grip. I can't decide between the RE-11's, RE-11a, Nt05/R888? It will be a daily driver in hot, cold and wet climates. I will also have upgraded RB's.

I must apologize for turning this into a tire thread. It was not my intent. Someone I trust greatly recently advised that he felt my issue was 70% tire and 30% yellow/purple power flex bushings being too soft.

If I had to do it again I would definitely go with stiffer bushings!