LS1GTO.com Forums banner

41 - 60 of 60 Posts

·
Registered
Joined
·
177 Posts
Discussion Starter #41

·
Registered
Joined
·
545 Posts
Why is that?
Because the stock inner control arm bushing is designed with voids to deflect as you adjust toe with the toe link. A homogenous poly bushing is not going to give like that, hence swapping over to the quad eccentric setup with no toe-links.
 

·
Registered
Joined
·
177 Posts
Discussion Starter #43
Because the stock inner control arm bushing is designed with voids to deflect as you adjust toe with the toe link. A homogenous poly bushing is not going to give like that, hence swapping over to the quad eccentric setup with no toe-links.
What's the better choice then, quad eccentrics or outer eccentrics with stock inners? If I leave the inners stock, would it be wise to replace the original stocks with replacement stocks?

Thank you for all of your help gentlemen.
 

·
Registered
Joined
·
545 Posts
What's the better choice then, quad eccentrics or outer eccentrics with stock inners? If I leave the inners stock, would it be wise to replace the original stocks with replacement stocks?

Thank you for all of your help gentlemen.

I went quad Whiteline eccentrics and deleted the toe rods. The downside is you have to trust alignment shops to figure out the alignment and tighten up the rear control arm bushings enough after adjusting them or they will come loose. This can be a real pain and may lead to more costly alignments down the road. Better is subjective. With the OEM inner and eccentric outer, you can set camber where you want it and alignments remain relatively simple, as toe is the critical one that may need adjustment more often. This is an easier, lower maintenance option but for max performance/aggressive alignments/track duty, going quad eccentrics should maintain alignment in hard cornering better.

If it was a spirited street car, I would personally do the eccentric on the outer only, and while I was in there just put a fresh OEM bushing on the inner. I do track days in mine though and run about -3 degrees of camber on all 4 corners.
 

·
Registered
Joined
·
177 Posts
Discussion Starter #45 (Edited)
I went quad Whiteline eccentrics and deleted the toe rods. The downside is you have to trust alignment shops to figure out the alignment and tighten up the rear control arm bushings enough after adjusting them or they will come loose. This can be a real pain and may lead to more costly alignments down the road. Better is subjective. With the OEM inner and eccentric outer, you can set camber where you want it and alignments remain relatively simple, as toe is the critical one that may need adjustment more often. This is an easier, lower maintenance option but for max performance/aggressive alignments/track duty, going quad eccentrics should maintain alignment in hard cornering better.

If it was a spirited street car, I would personally do the eccentric on the outer only, and while I was in there just put a fresh OEM bushing on the inner. I do track days in mine though and run about -3 degrees of camber on all 4 corners.
Fair enough, my car is typically a spirited street driver. It may see the track in the future after H/C/I/TB modifications. Can you point me to the right product links from GTOG8TA or Kollar?

Thank you!

A couple of other items I'm thinking of would be new spring pads (what size thickness?) and are there front outer control arm bushings or just inner?
 

·
Registered
Joined
·
8 Posts
No one mentioned (that I scanned), the reason you're rubbing after addressing the rear fenders is your wheel offset!
I ran 275/245 on widened stock 18's with Zero rubbing at any suspension deflection, because my overall wheel offset was more inboard than yours (I don't remember the exact numbers now, but can be calculated if required).
Just food for thought now that you're into upgrading the suspension anyways.
 

·
Registered
Joined
·
177 Posts
Discussion Starter #47
No one mentioned (that I scanned), the reason you're rubbing after addressing the rear fenders is your wheel offset!
I ran 275/245 on widened stock 18's with Zero rubbing at any suspension deflection, because my overall wheel offset was more inboard than yours (I don't remember the exact numbers now, but can be calculated if required).
Just food for thought now that you're into upgrading the suspension anyways.
Hmmm...in my previous threads about my wheel offsets and comparing them to other people's offsets with different rims, the consensus was that the offset was fine and that my suspension was shot.
 

·
Registered
Joined
·
177 Posts
Discussion Starter #48
Thank you to Duckman with Kollar Racing for the stellar customer service for helping me with my shopping list and offering some advice along the way. Here is what I ordered:

•MaverickManCarbon.com Front Coilovers
•MaverickManCarbon.com Rear Coilovers
•Polyurethane Bushing Front Sway Bar End Links
•Whiteline Front Polyurethane Upper Strut Mount Bushings
•Whiteline Rear Upper Shock Absorber Bushings
•Pedders Polyurethane Front Lower Control Arm Inner Bushings
•Whiteline Rear Control Arm Inner Bushings
•Whiteline Rear Control Arm Outer Bushings
•Pedders Polyurethane Front Radius Arm Bushings (Caster Adjustable)
•Pedders Polyurethane Rear Radius Arm Bushings
•Pedders Front Outer Tie Rod Ends
•Whiteline Rear Sway Bar End Link Bushings
•Whiteline Front Sway Bar Bushings
•Whiteline Rear Sway Bar Bushings
•Pedders Rear Subframe Mount Bushings
•Pedders Polyurethane Rear Differential Mount Insert
 

·
Registered
Joined
·
8 Posts
Hmmm...in my previous threads about my wheel offsets and comparing them to other people's offsets with different rims, the consensus was that the offset was fine and that my suspension was shot.
Just pointing out you can fit even bigger rubber under there with better offsets. Don't ask me for specific numbers though! FWIW.

Suspension work is always welcome. You seem to have a good handle with the list you are implementing. I'm just hoping you're not masking the root problem - of course it won't rub as much if you reduce/raise squat.
 

·
Registered
Joined
·
177 Posts
Discussion Starter #50
Just pointing out you can fit even bigger rubber under there with better offsets. Don't ask me for specific numbers though! FWIW.

Suspension work is always welcome. You seem to have a good handle with the list you are implementing. I'm just hoping you're not masking the root problem - of course it won't rub as much if you reduce/raise squat.
How do you know I can fit a bigger tire with better offsets if you don't know the offsets?

Weak sagging springs seem to be the root problem and they will be replaced by coilovers.
 

·
Registered
Joined
·
105 Posts
Looking good there. I would consider Hinson engine and transmission mounts if You don’t have it already. They won’t help with tire rub but truly transform the car feel from sloppy to solid. The car just becomes more fun to drive.
 

·
Registered
Joined
·
8 Posts
How do you know I can fit a bigger tire with better offsets if you don't know the offsets?
Because I have done it twice on LS2 GTO's, and based my implementation (at the time) on the original Brazen Orange GTO here on this site that first documented widened 18's with 275's.

FYI my setup was stock 18's widened 1.5" (9.5" resulting width), with a 1/2" spacer, whatever offset this comes out to be.
 

·
Registered
Joined
·
105 Posts
Because I have done it twice on LS2 GTO's, and based my implementation (at the time) on the original Brazen Orange GTO here on this site that first documented widened 18's with 275's.

FYI my setup was stock 18's widened 1.5" (9.5" resulting width), with a 1/2" spacer, whatever offset this comes out to be.
I think that works out to be 54 mm offset on 9.5” wheel. Sound right.
 

·
Registered
Joined
·
8 Posts

·
Registered
Joined
·
177 Posts
Discussion Starter #55
Looking good there. I would consider Hinson engine and transmission mounts if You don’t have it already. They won’t help with tire rub but truly transform the car feel from sloppy to solid. The car just becomes more fun to drive.
For now, I am doing Lou's Short Stick with the transmission detent plug modification. I will see how that feels, might snag the transmission mount insert from Revshift.
Because I have done it twice on LS2 GTO's, and based my implementation (at the time) on the original Brazen Orange GTO here on this site that first documented widened 18's with 275's.

FYI my setup was stock 18's widened 1.5" (9.5" resulting width), with a 1/2" spacer, whatever offset this comes out to be.
Fair enough, I'm 9 in wide right now with 45 offset. I'm not sure how 9.5 in wide at 54 offset compares, I'd have to do the math.
 

·
Registered
Joined
·
105 Posts
I think it is not recommended to install poly transmission mount without installing engine mounts as well. It’s ok to do it the other way around.
 

·
Registered
Joined
·
177 Posts
Discussion Starter #57
I think it is not recommended to install poly transmission mount without installing engine mounts as well. It’s ok to do it the other way around.
Sounds good, thanks for the tip!
 

·
Registered
Joined
·
211 Posts
OP, did you get all of your parts installed? I recently upgraded to VMR 710s 18x8.5 45 front and 18x9.5 45 rear. Tires are 235/40/18 front and 265/35/18 rear. Rear slightly rubbed going into dips and turns until I had the fenders rolled. My GTO has Lovells 20mm drop springs and KYB shocks all around. I have no rubbing whatsoever now. I also had an alignment done, but haven't replaced any rear bushings apart from the subframe bushings.
 

·
Registered
Joined
·
177 Posts
Discussion Starter #59
OP, did you get all of your parts installed? I recently upgraded to VMR 710s 18x8.5 45 front and 18x9.5 45 rear. Tires are 235/40/18 front and 265/35/18 rear. Rear slightly rubbed going into dips and turns until I had the fenders rolled. My GTO has Lovells 20mm drop springs and KYB shocks all around. I have no rubbing whatsoever now. I also had an alignment done, but haven't replaced any rear bushings apart from the subframe bushings.
EZ28, I just ordered the parts the other day, won't be here until next week, and the install will be a learning process for me. But you have the same tire sizes as me, and I rubbed in the rear until I cut my fender lips down to a half inch. No more rubbing which is great, but a terrible squat on launch. Time to tighten up the rear end and keep the car level.
 
41 - 60 of 60 Posts
Top