street car suspension problems! - F-Body Road Racing and Autocross Forums

Newbie here, hello. Car is a 1995 Formula. Set up for Ozark road trips loaded full of camping gear, driven legally but aggressively on mostly great pavement. Planning to start doing a few autocross events/yr. Here's a rundown of current setup, which I gather is a mishmash of all the wrong parts. Most of this crap, I understand, is designed for straight-line racing and/or impressing techs at tire and muffler shops. Any advice is welcome.

-Stock 16x8 wheels, 245/50/16 BFG G-force SS, 37psi front/32psi rear cold pressure.
-BMR goodies (yeah, I know) - rear control arms (non-adjustable, poly bushings), welded frame connectors, strut tower brace, adjustable panhard rod (poly both ends), stock torque arm.
-Eibach pro-kit springs
-Bilstein HD shocks
-poly motor + trans mounts
-stock sway bars w/ poly end link and clamp bushings.

The car has gained a "bit" of power recently thanks to cam and head work and some old fashioned displacement, and the weaknesses are beginning to show.

Issue #1: The car now squirms around in the rear on hard acceleration, even with no apparent wheelspin. Quite frightening. Difficult to keep it in it's lane even when accelerating from 40-60mph. The rear axle seems to be steering the car.

Issue #2: A recent alignment indicated something funny. Camber and caster were no problem, but with the tie rods adjusted to the limit, toe setting is 1/8" out. No less can be had. Previous alignments presented no problems with setting toe to zero, which I always preferred. Is it possible that the wrong tie rod ends were installed at some point, or is this a function of the lowering springs? How durable are the spindles, and should I suspect them as well after 135k miles?

Question: Should the rear control arms be relocated for the lowered ride height, or is that another Summit catalog myth? Launch traction is definitely reduced now that it sits lower.

Also, the car is under-represented in the braking department. C-5/C-6 brakes or something aftermarket? Don't really want to go larger than 17" wheels.

QUOTE (Gradinger @ Dec 15 2010, 05:57 PM)

Set up for Ozark road trips loaded full of camping gear

Sorry for the off topic, but Ozark as in Southern Missouri or northern Arkansas? If so, where do you plan to auto-x?

Only other thing I have to add is that I've got C6 brakes (using Trackbrackets!) on the front of my 93 and I love them more every time I drive it. Night and day compared to the stock LT1 brakes. Good stuff.

QUOTE (RumbleZ @ Dec 20 2010, 07:35 AM)

QUOTE (Gradinger @ Dec 15 2010, 05:57 PM)

Set up for Ozark road trips loaded full of camping gear

Southern Missouri, not Arkansas. I live in Memphis, and with any luck, the track here will be ready for the spring season. It was just sold last week after sitting dormant all year.

Thanks for all the advice, plenty to check on next time I get the car up. The bushings are fairly new all around, with the exception of the torque arm. The plan for now is to replace tie rod ends and ball joints (again) and to replace the rear control arms and panhard bar with rod ends rather than bushings. I also plan to replace the torque arm, just because. Re-align, re-apply thottle, re-assess. Once the bad manners are sorted out, time for a brake upgrade.

Gradinger View Member Profile	Dec 15 2010, 11:57 PM Post #1
newbie Group: Members Posts: 6 Joined: 10-December 10 Member No.: 32,953	Newbie here, hello. Car is a 1995 Formula. Set up for Ozark road trips loaded full of camping gear, driven legally but aggressively on mostly great pavement. Planning to start doing a few autocross events/yr. Here's a rundown of current setup, which I gather is a mishmash of all the wrong parts. Most of this crap, I understand, is designed for straight-line racing and/or impressing techs at tire and muffler shops. Any advice is welcome. -Stock 16x8 wheels, 245/50/16 BFG G-force SS, 37psi front/32psi rear cold pressure. -BMR goodies (yeah, I know) - rear control arms (non-adjustable, poly bushings), welded frame connectors, strut tower brace, adjustable panhard rod (poly both ends), stock torque arm. -Eibach pro-kit springs -Bilstein HD shocks -poly motor + trans mounts -stock sway bars w/ poly end link and clamp bushings. The car has gained a "bit" of power recently thanks to cam and head work and some old fashioned displacement, and the weaknesses are beginning to show. Issue #1: The car now squirms around in the rear on hard acceleration, even with no apparent wheelspin. Quite frightening. Difficult to keep it in it's lane even when accelerating from 40-60mph. The rear axle seems to be steering the car. Issue #2: A recent alignment indicated something funny. Camber and caster were no problem, but with the tie rods adjusted to the limit, toe setting is 1/8" out. No less can be had. Previous alignments presented no problems with setting toe to zero, which I always preferred. Is it possible that the wrong tie rod ends were installed at some point, or is this a function of the lowering springs? How durable are the spindles, and should I suspect them as well after 135k miles? Question: Should the rear control arms be relocated for the lowered ride height, or is that another Summit catalog myth? Launch traction is definitely reduced now that it sits lower. Also, the car is under-represented in the braking department. C-5/C-6 brakes or something aftermarket? Don't really want to go larger than 17" wheels.

RumbleZ View Member Profile	Dec 20 2010, 01:35 PM Post #2
Member Group: Advanced Members Posts: 58 Joined: 30-August 07 From: SW Missouri Member No.: 1,926	QUOTE (Gradinger @ Dec 15 2010, 05:57 PM) Set up for Ozark road trips loaded full of camping gear Sorry for the off topic, but Ozark as in Southern Missouri or northern Arkansas? If so, where do you plan to auto-x? Only other thing I have to add is that I've got C6 brakes (using Trackbrackets!) on the front of my 93 and I love them more every time I drive it. Night and day compared to the stock LT1 brakes. Good stuff.

Gradinger View Member Profile	Dec 25 2010, 02:25 AM Post #3
newbie Group: Members Posts: 6 Joined: 10-December 10 Member No.: 32,953	QUOTE (RumbleZ @ Dec 20 2010, 07:35 AM) QUOTE (Gradinger @ Dec 15 2010, 05:57 PM) Set up for Ozark road trips loaded full of camping gear Sorry for the off topic, but Ozark as in Southern Missouri or northern Arkansas? If so, where do you plan to auto-x? Only other thing I have to add is that I've got C6 brakes (using Trackbrackets!) on the front of my 93 and I love them more every time I drive it. Night and day compared to the stock LT1 brakes. Good stuff. Southern Missouri, not Arkansas. I live in Memphis, and with any luck, the track here will be ready for the spring season. It was just sold last week after sitting dormant all year. Thanks for all the advice, plenty to check on next time I get the car up. The bushings are fairly new all around, with the exception of the torque arm. The plan for now is to replace tie rod ends and ball joints (again) and to replace the rear control arms and panhard bar with rod ends rather than bushings. I also plan to replace the torque arm, just because. Re-align, re-apply thottle, re-assess. Once the bad manners are sorted out, time for a brake upgrade.