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Adjustable strut and shock advice

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Old 09-22-2024, 03:58 PM
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Adjustable strut and shock advice

Looking for adjustable strut and shock advice from people with a similar set up. I don't have any experience with them. My Car, 1986 Trans Am, hard top, fully optioned, drag strip 2x a month, no autocross, otherwise a cruiser. Motown 454 sbc, AFR 235 Eliminators, Howards cam-110275-12s, 1.65 roller rockers, ported Miniram 2, Hooker 2210's, Mufflex 4 inch exhaust, Probuilt 700r4, Yank 3200 converter, Strange 12 bolt 3.73. Inner and outer sfc, welded, Spohn adjustable Torque arm on crossmember, CE lca and track bar, BMR lca relocation brackets, Eibach Prokit with kyb gr2 struts and kyb gas adjust shocks. New Mickey Thompson ET streets-255/50-16.
Pinion angle at-3 degrees, lca in btm hole, ET streets at 18 psi, tires break loose even from a roll in 1st and 2nd, move the lca to the top hole and traction improves a lot, but still breaks loose at 4-5000 rpm in 1st and 2nd. With either setting, i have to roll into the throttle from a standing start, flooring it will break it loose immediately. Assuming adjustable struts and shocks are the next move, but have 0 experience with them. I have read many threads on this, with no clear answer. Koni's appear to be the favorite, with Tokico not available and KYB Agx a distant 3rd. Is a double adjustable strut needed for this application or would a single be ok? Would Kyb agx give me the weight trans for that I need? Not set on any brand, Just bang for the buck.
This was all backroad testing, test and tune at the local track was rained out last Friday. Track will be closed for the season after this weekend.
Thanks for looking!
Old 09-28-2024, 08:12 AM
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Re: Adjustable strut and shock advice

Originally Posted by 86 406
Looking for adjustable strut and shock advice from people with a similar set up. I don't have any experience with them. My Car, 1986 Trans Am, hard top, fully optioned, drag strip 2x a month, no autocross, otherwise a cruiser. Motown 454 sbc, AFR 235 Eliminators, Howards cam-110275-12s, 1.65 roller rockers, ported Miniram 2, Hooker 2210's, Mufflex 4 inch exhaust, Probuilt 700r4, Yank 3200 converter, Strange 12 bolt 3.73. Inner and outer sfc, welded, Spohn adjustable Torque arm on crossmember, CE lca and track bar, BMR lca relocation brackets, Eibach Prokit with kyb gr2 struts and kyb gas adjust shocks. New Mickey Thompson ET streets-255/50-16.
Pinion angle at-3 degrees, lca in btm hole, ET streets at 18 psi, tires break loose even from a roll in 1st and 2nd, move the lca to the top hole and traction improves a lot, but still breaks loose at 4-5000 rpm in 1st and 2nd. With either setting, i have to roll into the throttle from a standing start, flooring it will break it loose immediately. Assuming adjustable struts and shocks are the next move, but have 0 experience with them. I have read many threads on this, with no clear answer. Koni's appear to be the favorite, with Tokico not available and KYB Agx a distant 3rd. Is a double adjustable strut needed for this application or would a single be ok? Would Kyb agx give me the weight trans for that I need? Not set on any brand, Just bang for the buck.
This was all backroad testing, test and tune at the local track was rained out last Friday. Track will be closed for the season after this weekend.
Thanks for looking!
I'm running a turbo LS fully built and with Koni adjustable struts and QA1 single adjustable rear shocks. I've got the struts about 1.5 turns in and the shocks at 6 clicks, LCA's at the bottom hole and my torque arm is in the second hole from bottom. Pinion angle -2*. Tires are 275/40-17 Mickey Thompson drag radial 25 psi.

With mine set up like so I can hammer it off the line and it keeps traction much better than when I was hitting the tires a bit harder with the torque arm in the 3rd or 4th hole up.
Old 09-28-2024, 04:52 PM
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Re: Adjustable strut and shock advice

Hello, thanks for responding, your car sounds like a lot of fun. I have the torque arm in the 3rd hole, I'll drop that and move the LCA's back to the bottom hole and see what happens. Koni adjustables will be the next move. Noticed you have Koni's on the front and QA1 on the rear. Do you find there is an advantage to this combo, rather than Koni's all around?



Old 09-28-2024, 07:25 PM
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Re: Adjustable strut and shock advice

Originally Posted by 86 406
Hello, thanks for responding, your car sounds like a lot of fun. I have the torque arm in the 3rd hole, I'll drop that and move the LCA's back to the bottom hole and see what happens. Koni adjustables will be the next move. Noticed you have Koni's on the front and QA1 on the rear. Do you find there is an advantage to this combo, rather than Koni's all around?



No advantage to the 2 brands I bought the Koni struts on sale for like 45% off and the QA1 shocks were the right price and in stock. That's really the whole reason for two brands of shocks. I do really like the QA1 shocks out back they are really sensitive to the adjustments.

For the front torque arm adjustment the higher up you go the harder it's gonna hit the tires. I've got 5 holes for adjustment on mine. I only made it up to 3 before realizing any higher was not gonna be worth it
Old 09-28-2024, 11:55 PM
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Re: Adjustable strut and shock advice

* Pinion angle should be adjusted for smooth operation of the driveshaft and health of the u-joints.

* It will help you tremendously if the rear shocks have adjustable compression (not just rebound).

* If car is lowered then make sure axle is not hitting the rear bump stops, that will cause tires to spin instantly. This might be a problem given your descriptions.

* Torque arm: Raising the front mount raises instant center. It doesn't have a very strong effect on it though.

* Rear control arms: Begin with 1° - 2° slope downward toward axle. Moving to a lower position on axle will raise instant center, and it has a strong effect on it. I would just leave it at these numbers while you work on other issues.

* Throttle control. Seriously. You have a 454 stroker.... it has mega throttle response. Don't snap the throttle, roll into it.


* Street driving murders 0 treadwear rubber. It maybe could be your tires are just getting more slippery too.

By the way, I suck at drag racing sooooooo.... just being transparent and honest about that.
Old Yesterday, 12:05 AM
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Re: Adjustable strut and shock advice

Also, you want a drag car but your suspension is more autocross than it is drag. I had autocross suspension with drag radials and the car did everything poorly. Been there, done that.... best to choose one or the other and commit to suspension philosophy that goes with it.

I do have experience with that! LOL!
Old Yesterday, 03:16 PM
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Re: Adjustable strut and shock advice

Thanks for the responses and advice guys. I understand the difficulty in trying to set up a dual purpose car. I'm the original owner, and a lot of the mods were done as the factory parts wore out, without a clear goal in mind. I've had several different engines in it over the years, and as power levels increase, traction becomes more difficult to obtain. Each swap is a learning experience. I'm going to try to crutch a less than ideal suspension set up with adjustable struts and shocks to make acceptable passes at the local track, which is open 2 weekends a month during the season. The track runs under NHRA rules, so if the car runs under 11.5's, I'll need a roll bar, which I don't have now. That will open another can of worms. Very few Third Gens come out, so its nice to put up a good effort. Thanks for looking.
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