More suspension upgrade info/FYI's

[GNVAIR]

Well, I have been playing around with my GN figuring how I can improve/tune what I have done thus far. For those that havent been involved in the previous threads, I will include a list of the mods as they presently stand.
b body spindles
12 inch 1LE rotors
b body master cylinder and calipers
Performance Friction pads
Del Alum lower control arm bushings
Global West upper control arms with Del Alum on left and brass on right
Bilstein Shocks (front and rear)
Moog 5660 front coil springs
Stock front sway bar with new stock bushings and urethane endlink bushings
Moog idler arm, centerlink, inner and outer tie rods
Hotchkiss tie rod sleeves
Perfect Circle lower ball joints
16x8" GTA rims (rear offset on the front and front offset on the rear)
Kumho Ecsta Supra 712 tires (P245/50ZR16 fronts, P255/50ZR16 rears)
Alignment set at 4.9°+ caster, -.9° camber, toe -1/16"
Some of the things I have noticed thus far. Steering seems good even though there is a little slop/travel in the wheel. Upon checking it out this weekend I found 2 things. First is my 130k mile stock steering box needed an adjustment. I got almost 2 full turns down on the adjustment screw
After taking up the slop in the box, I still had slop in the steering wheel. I checked out the linkage and found the pot joint at the base of the steering column had the boot torn open.........this seems to be common on a lot of the TR's I have looked at and might possibly be from the excessive heat that these engines can give off. The pot joint was wasted with a ton of lateral slop. When I grabbed it, it made an audible "clunk" noise. I also noticed that the column had some slop at the bottom. After checking out every g body in the U Pull it yard yesterday, I concluded that this is probably common. I located a very tight steering shaft with the pot joing and will be installing that for the time being. What I am planning to do is to contact Borgeson to see if they could make a "solid" steering shaft with 2 U joints and a telescoping shaft to take the place of the pot joint and rag joint.
As for another area I have been looking into is the rear suspension. I ordered an ATR rear sway bar and am hoping that it will solve the "loose" rear end feel that I currently have with my car. I will be doing this along with reconditioning my control arms with some needed reinforcements.
As for the bumpsteer issue, I found this on the www.montecarloss.com site last night. Pretty neat set up for eliminating the bumpsteer. http://jeffd.50megs.com/bump_steer_mods_page.htm

 

[RealFastV6]

Looking at your suspension mods list... You have nothing done to the rear suspension at all. Am I missing something?

I'd at the very least box the stock control arms (upper AND lower) and press some graphite or polyurathane bushings in. The ATR bar will tie everything together much better if there isn't so much slop in the control arms and control arm bushings.

 

[GNVAIR]

I forgot to mention that I have Moog cargo coils in the back (they really are a progressive rate spring), 1LE bushings in the control arms. I am going to box the control arms in more. When I said loose, I meant it seems to have more body roll in the back which can probably be attributed to the puny stock rear sway bar.
You will NEVER see any of my cars with any type of solid or polyurethane bushings in the control arms.

 

[SSYNERGY]

Hey Lee, it's Ashley, regarding the BORGESON setup, I've had one on my car for about a year now, and it works great. The problem is the setup cost me $250 for the 3 pieces. HTH's

Emial me and I will provide you with the complete list of parts needed for our cars. Or you can priviate message me on the Monte SS site. This BORGESON setup is BOSS, you will NEVER regret it .

 

[GNVAIR]

I am looking into this set up as most of the shafts I looked at in the yard yesterday were loose as mine is. I checked my father's low mileage Monte SS and his is the same way. This is totally unacceptable to me.

 

[GNVAIR]

Latest upgrades completed

As of last night I boxed all 4 of the rear control arms, replaced all 8 bushings with a new set of 1LE spec (higher durometer rubber) bushings and added an ATR rear sway bar.
The difference is nothing short of astounding. All of the roll in the rear has disappeared. Ride quality is slightly stiffer, but not obnoxious. Throttle on oversteer is just a tickle of the gas pedal away. Some people might not like it, but I simply love it. There are 5 other things I have in store next.
1) Add 5/8" rear wheel spacers to move the GTA rims outward and increase the rear track width.
2) To replace the unknown age/mileage/spring rate cargo coils with Moog 6435's to lower the back end down a tad.
3) To replace the sloppy factory steering shaft/rag joint with a set of precise Borgeson units AND to go through the steering box and reset the preload in the bearings.
4) To replace all of the factory body bushings with new facory units along with adding the missing ones
5) Add additional body bracing. I currently have the lower frame braces in the front. I would like to add the Gran Prix cross brace in the front. Fabricate new upper fender to rad support braces that actually work, fabricate trunk braces and fabricate a rear brace in front of the rear bumper to connect the rear frame rails.
I know it sounds like a lot more, but its actually not. This will obviously be an on going project. I will post updates from time to time so others can duplicate or see what I have experienced.

 

[SSYNERGY]

Hey Lee, could you email me the link to ATR's site, I can never find it and I've been wanting to get one of those REAR SWAY-BARS for a long time now. I don't even know the cost of that BAR. Thanks buddy.

 

[GNVAIR]

Ashley, I believe it cost me $179.95 + shipping. Definitely plan on replacing the mounting nuts and bolts they supply with something substantial like grade 10 since this bar is huge and will break/loosen the 3/8" stainless bolts they provide. Here is a link to their site http://www.atrperformance.com/

 

[BlackBuickBeast]

That sounds great. It's nice to see more and more people are trying to make our cars handle. I would say the biggest piece that your missing is a nice 6point cage. That would tie the car together great. That's is if you want to spend the money.

After you get the rest of your stuff it would be real instresting if you could go to a skid pade or salom and get some number to compare to a new cobra or vette.

 

[c&cgn]

My question for GNVAIR:

Have you ever had your car to the track?

What did it 60' at the time?


Are you going to be taking it to the track and see what it 60's now?

Sounds like the car will handle real well in the twisties but what about hooking up in a straight line?

I would like to have the best of both worlds.

Clayton

 

[GNVAIR]

Both times I ran it at the track on the sloppy/worn out stock suspension it was run on radials. I will be taking it to the track soon to test out some of my other mods. I will be using a set of 26x10.50 Mickey T ET steets mounted on an extra set of rims. I will let you know.

 

[tminer]

Lee,

I can't find any info on the 6435's. do you have the specs or a link to more info?

Thanks,
Tom Miner

 

[GNVAIR]

The 6435's are a specific rate spring rated at approx 140lb/in.
They are available from Moog. I just paid $58 for them locally. I am going to install them tonight.

 

[motorhead]

Well, this all fine and dandy... but what shocks are you running or planning to run?

If you are running around on some crappy gas shocks (in the rear in particular) you are going to find that when you swap them out for KYBs, Konis, or QA1s that the gigantic ATR bar is going to cause massive oversteer issues.

Like yourself, I am planning on road racing a G-body... and it seems that you have an excellent project setup on the go... But, you are going to hate that big bar in the end. IIRC, Herb Adams offers a smaller bar than the ATR unit and that would be more applicable to our needs.

What about swapping a few pounds off the front with an F-body 34 or 36mm hollow bar? Could aid in the ATR bar OS issue.

Did you consider the Moog CC635s in the rear? They are progressive from 104# and are trimable for increased rate and stance (lowering the CG). I am planning on teaming these with cut 5664s in the front (yeilding about 840#s), and I am still unsure of what spring to run in the rear to attain the best possible wieght transfer through a corner.

Any thoughts?

Got pics?

 

[GNVAIR]

If you read the post you will know that I have Bilstein's all the way around. The reason why I am swapping the springs is to bring the back end down to match my 5660 front springs. I picked the specific rate 6435's based on someone else's suggestion. I will be teaming these with the stock sway bar for now and might try the slightly larger Addco/GW/Hotchkis 1" rear bar.

 

[GNVAIR]

I installed the Moog 6435's last night and reinstalled my stock rear sway bar. I really like this set up. The ride is stock and there is plenty of grip at the rear end now. There is just enough roll to the body to allow grip on the rear tires. With the ATR bar and the unknown cargo coils there was no roll and as such.....the rear end would hit the limits of its travel and then slide.
On my road test, I took the car down a road we have here that is all switch back turns and I was taking them at close to 70mph last night!!
The ATR bar is being donated to a friends project. Next step for me will be the steering box rebuild, steering shaft upgrade and some new body bushings. All should make substantial differences.

 

[SSYNERGY]

BORGESON setup and STEERING BOXES

Hey Lee, have you contacted BORGESON yet ? Also, are you doing the steering box rebuild yourself, or are you sending it out to LEE MANUFACTORING in California? My 88 GTA box is great on the street, but logic suggests that this same 12.7:1 ratio would be DANGEROUS for OPEN ROAD RACING. I know that the NASCAR RESTRICTOR PLATE CARS, use a 16.5:1 ratio box on those tracks, and so do all of the TRUE-VALUE "IROC" cars. I have a what I think is a 14:1 box out of a 91 V-6 RS, that I would like to have prepped to use in those events. I think that some of the STOCK V-6 G-bodies came with a 16:1 ratio box as well, but I don't know if these boxes are the GM 605's or if they are 800 SAGINAW's. I guess I will have to ask the guys at LEE's Manufactoring some more.

BTW, about the BORGESON setup, spend the extra money and get the STAINLESS STEEL U-JOINT and VIBRATION U-JOINT. Mine are showing some surface rust because of water exposure, and now I have to remove them and prep and paint them . Oh well

 

[motorhead]

Originally posted by GNVAIR
If you read the post you will know that I have Bilstein's all the way around.

D'Oh! Sorry, that was a very heathly list... I was bound to miss something.

The reason why I am swapping the springs is to bring the back end down to match my 5660 front springs. I picked the specific rate 6435's based on someone else's suggestion. I will be teaming these with the stock sway bar for now and might try the slightly larger Addco/GW/Hotchkis 1" rear bar.

...Yeah, I hear ya. The 1" sounds more promising to me.

Did you know that there is a G-body chassis mailing list? We talk this stuff all the time... if you are interested PM or email me for the info.

 

[GNVAIR]

Ashley, I havent ordered the pieces. I am dealing with multiple projects right now that I am trying to take care of. I will most likely order the pieces within the next few weeks. I plan on doing my own box using this article which is excellent http://www.monte-list.nu/tech/boxmesh.shtml
As far as the steering boxes go. The stock fast ratio Monte/GN/442 boxes AND the WS6/IROC boxes are great for the street and autocross with their quick ratios, but for road racing, you might want to consider one of the standard Saginaw 800 boxes from a standard G body with their slower ratios. If you are worried about road feel, you can replace the spool valve in the box with the one from the WS6/IROC box and do the power steering pump mods that Jeff Davidson has listed on his site. IMHO, this would be the way to go; especially if you plan on running the 160mph class in the Silver State. Here is a link to the mod http://jeffd.50megs.com/Pump_valve_mod_page.htm
Im sure you know how to id the Saginaw 800 box (4 bolt aluminum top cover as opposed to the round snap ring retained cover of the 605 box). The box you would want to start with can he had from any of the generic standard g bodies that have the 800 box.

 

[tminer]

Lee,

I can't seem to find any info on the rear springs (6435) that you are using. Do you have the specs or a link to them. I got my latest hp upgrades done and decided that I'd better do brakes and suspension sooner instead of later.

Thanks,
Tom