The weekend tracker's suspension guide....help!

[forcefeedme]

Well, im new to the G-body crowd. I've been searching for the proper way to set up the suspension on my car without much satisfaction.

I sometimes drive the car to work, bring it out on cruise nights, and plan on taking her to the track often.... which i assume is the norm for most people on the boards.

I bought the car how it currently is.

Boxed stock lower control arms
Lower relocation brackets (that move the LCA's upward )
Stock upper control arms
Stock sway bar
Stock springs
Bilsteins
Dual air bags
MT ET street 28x13.5 slicks
Not sure on the pinion angle.
3.42 locked rear

Also has....
pt63 nonBB turbo
built 200r4 (which i plan on selling, and replacing with a th400)

I was able to pull off a 1.76 60' launching with around 4psi.I will say that the car did squat alot. I would like to be able to get the car down to the 1.5x range, yet still be somewhat streetable. I am willing to sacrifise ride quality for performance.

From some of the research i have done, and after talking to a few g-body owners, here is what i've come up with...

-Stock boxed lowers should be fine, but aftermarket ones would be better
-Adjustable upper control arms
-1 3/8" rear sway bar will be sufficient (fulthrottle)
-Take current relocation brackets out, add lowering relocation brackets.
-Poly bushings all around
-Stiffer rear spring (moroso trick)

I've also been reading that lowering the rear mounting point of the lower control arms actually may inhibit wheel hop. Ive heard people say to leave the mounting position in the stock location. What do you guys have to say about that?

I would like to see some good constructive advice. Help me acheive a 1.5x 60'

Thanks in advance.

 

[DCVING 6]

HRpartsNstuff "Your WWW performance parts supplier"

 

[johnplogii]

I have never seen relocation brackets that move the mounting point up for the lowers. They either move the rear of the lowers down or the rear of the uppers up. Can you elaborate on this? Is the car spinning? Tires and wheels are very inportant. I never had luck with the et street bias ply tires. What width is your rim?

 

[Roc87]

I have never had much luck with ET Streets, didn't seem to have much luck with ET drags either. How many pounds of boost were you leaving with? Is the posi working correctly?

 

[forcefeedme]

I have never seen relocation brackets that move the mounting point up for the lowers. They either move the rear of the lowers down or the rear of the uppers up. Can you elaborate on this? Is the car spinning? Tires and wheels are very inportant. I never had luck with the et street bias ply tires. What width is your rim?

Im not joking, the car has relocation brackets that are upside down, moving the rear of the lower control arm upwards.

Im using 28" tall, 13.5" wide MT ET Streets. I cant even do a burnout without there being water on the tires. Wheels are 15x10 in the rear.

I left with about 4psi and i didnt spin.

 

[forcefeedme]

I have never had much luck with ET Streets, didn't seem to have much luck with ET drags either. How many pounds of boost were you leaving with? Is the posi working correctly?

I personally like the hoosier quicktime pros much better, and ill be getting a set of them once these MT's wear down.

I left with about 4 pounds, didnt spin. Posi works fine. Car did squat considerably.

I will say that i probably could have left with more boost, but my friend told me the tires sounded like they were close to losing traction... and that was at 4psi.

BTW... i ran 14psi tire pressure in both tires. Would it benifit to go lower? 13? 12?

 

[Roc87]

Numberous guys around here liked the Hoosier QTP's also. I was going to give them a shot, but since I rarely make it to the track I picked up a pair of M&H 275/55/16 DR's. Even aired up at 28#, they held a 4# launch on the street with no burnout. I tried a 6# launch and even though it felt like it launched much harder, they did spin a turn or two.... That's about the time the tranny flare made itself VERY appearent, so no new track times yet. Personally I wouldn't go much lower than 14# in the ET Street or ET Drags. I tried 12# and it was WAY too "squirelly" at the top end and that was with 26" tires, can't imagine what that extra sidewall height would do .
Those relocation brackets being on upside down are probably not helping. I'd look into getting a new set and having the old ones cut off and the new ones installed correctly.

 

[Chuck Leeper]

My $.02

"Girls squat, race cars don't". You tune the suspension w/ the IC, % of rise, and the shocks, tires, ft suspension. The springs are there to do 1 thing, support the wt of the car.
I've built many sets of relo brkts, and see no way to move the LCA up.. The LCA fits in the axle brkt, and would hit the lower side of the axle tube, if one attempted to raise it. What you may be seeing, is the relo brkts are of a design that bolts to the OEM brkt, using the original holes. The previous owner has put the LCA's back to the OEM location, leaving the relos in place, [welded on?] thus the appearance of "raising" the bars.
A. Adjustable uppers w/ pinion angle to 3-4* down.
B. Dbl adjustable shocks at all 4 corners.
C. HR antiroll bar. [Ditch the air bags.]
D. A pr of BBC Moroso ft springs.
E. Videos of the car launching, will provide LOTS of good info as to how well things are working. [Or not]
And, 1 thing I've found to be VERY important: A good alignment! You can EASILY add a tenth with a bad alignment.
Start w/ the shocks in a midpoint setting, tires at the mfgr recommended psi, and a repeatable burnout proceedure. Make LOTS of notes, and see where the times are headed after each change. REMEMBER: Change 1 thing at a time!
Tires need to be 10-15* hotter than the track surface... No need for a T/F burnout.. All that does is make the tire vendors :biggrin:

Just my $.02.. It worked for me.

 

[forcefeedme]

"Girls squat, race cars don't". You tune the suspension w/ the IC, % of rise, and the shocks, tires, ft suspension. The springs are there to do 1 thing, support the wt of the car.
I've built many sets of relo brkts, and see no way to move the LCA up.. The LCA fits in the axle brkt, and would hit the lower side of the axle tube, if one attempted to raise it. What you may be seeing, is the relo brkts are of a design that bolts to the OEM brkt, using the original holes. The previous owner has put the LCA's back to the OEM location, leaving the relos in place, [welded on?] thus the appearance of "raising" the bars.
A. Adjustable uppers w/ pinion angle to 3-4* down.
B. Dbl adjustable shocks at all 4 corners.
C. HR antiroll bar. [Ditch the air bags.]
D. A pr of BBC Moroso ft springs.
E. Videos of the car launching, will provide LOTS of good info as to how well things are working. [Or not]
And, 1 thing I've found to be VERY important: A good alignment! You can EASILY add a tenth with a bad alignment.
Start w/ the shocks in a midpoint setting, tires at the mfgr recommended psi, and a repeatable burnout proceedure. Make LOTS of notes, and see where the times are headed after each change. REMEMBER: Change 1 thing at a time!
Tires need to be 10-15* hotter than the track surface... No need for a T/F burnout.. All that does is make the tire vendors :biggrin:

Just my $.02.. It worked for me.

You are probably right about the relocation brackets. Ill have to look at it better.

1. ill get adjustable uppers....keep the boxed stock lowers or should i go with lift bars?

2. i have bilsteins, which arent adjustable. Which ones do you recommend? How about 90/10's or 70/30's? Most people seem to use 90/10's.

3. ill be getting the 1 3/8" rear bar from full throttle

4. Can you explain why BBC front springs would benefit? Is this to make the front of the car sit higher?

Thanks for your input.

 

[Chuck Leeper]

Some more of..

You are probably right about the relocation brackets. Ill have to look at it better.

1. ill get adjustable uppers....keep the boxed stock lowers or should i go with lift bars?

2. i have bilsteins, which arent adjustable. Which ones do you recommend? How about 90/10's or 70/30's? Most people seem to use 90/10's.

3. ill be getting the 1 3/8" rear bar from full throttle

4. Can you explain why BBC front springs would benefit? Is this to make the front of the car sit higher?

Thanks for your input.

"my $.02"...

1. Adjustable uppers are a good investment. They make setting pinion angle possible.

2. By adjustable shocks, I meant Konis, HAls, etc. They are adjustable on the car, by use of adj knobs. They are not cheap, but can be set back to "street" settings, while the 70/30, types are a PITA to adjust. [Have to be removed in most cases.]

3. The big rear swaybar, mounted in the OEM location, on stock arms, can be so stiff it will distort the arms. The HR bar does not fasten on the arms, so that problem is eliminated. The HR bar is adjustable, the other is not.

4. The Moroso BBC springs allow for easier/faster ft end rise, on launch. They do not make the car sit higher. Faster ft rise allows for faster pitch rotation, and wt transfer to the rear tires.

Like I said, my $.02. That combo worked for me...

 

[forcefeedme]

"my $.02"...

1. Adjustable uppers are a good investment. They make setting pinion angle possible.

2. By adjustable shocks, I meant Konis, HAls, etc. They are adjustable on the car, by use of adj knobs. They are not cheap, but can be set back to "street" settings, while the 70/30, types are a PITA to adjust. [Have to be removed in most cases.]

3. The big rear swaybar, mounted in the OEM location, on stock arms, can be so stiff it will distort the arms. The HR bar does not fasten on the arms, so that problem is eliminated. The HR bar is adjustable, the other is not.

4. The Moroso BBC springs allow for easier/faster ft end rise, on launch. They do not make the car sit higher. Faster ft rise allows for faster pitch rotation, and wt transfer to the rear tires.

Like I said, my $.02. That combo worked for me...

I really appriciate your advice.