Hook set up questions

[rockinjester]

Situation: hooking on inital launch then going into spin. Car starts to lift the front end then slams to the ground. Have tried multiple set ups but have had same results.

Tires: 28 x 10.5 x 15 MT Slicks air adjustments numerous 9 to 15 PSI.
Transbrake - launch at 42-4400.

1) Set up One: negative 2 degree pinion angle - solid double adjustable UCA'S - weight jackers LCA - Moroso coil springs - Comp Eng. 3 way drag shocks with anti-body roll bar.
60' -1.38-1.46

2) Set up Two: Same as above but with airbag. 8-15 psi pass 1-5 drive.
without airbag car squats and eats the tires. with airbag horrible 60' and ET times but dont shave the tires.

3) New Set up: Same UCA'S with new solid LCA'S without coil springs - chassis engineering coil over conversion mount kit for stock shock location -strange single adjustable coil overs with 150 lb springs - anti-body roll bar kit.

Any suggestions how I can set this up to keep the wheelwells from squating down on the tires without minitubs and best set up for my package?:eek:

[KEVINS]

The squating is due to the stock control arm geometry placing the Instant Center too far forward and this causes the tires to unload. What front struts do you have? The 150# rear springs are pretty stiff and you should look into something around 110#.

HTH's
ks

[jmood45]

i had the same problem a few years ago. i changed my front struts fom 90/10 to 70/30 and it solved the problem.

[rockinjester]

Kevin, the fronts are lakewood 70/30 coilover conversions on a tube k-member and a-arms. The reason for the 150# rear springs is. They are what chassis engineering suggested. By the way this is an 82 Hatch if that makes any difference or not on spring suggestion.

[KEVINS]

Those struts should be fine. What front springs are you running and how much "available" travel do you have?

KS

[rockinjester]

I think they are 160# and are set mid way on the coil tube. When sitting still w/me in it the front top of tire is exposed aprox. 2" and has 5 to 6"of travel

[KEVINS]

Have you ever plotted the Instant Center to see where it's located?
I don't see anything that drastically stands out right now except the IC location being unknown. Do you have a good vid of the launches you can email me so I can see what's it's doing?

Tech@baselinesuspensions.com

ks

[rockinjester]

Kevin sorry to be getting back to you so late but it statred getting late last night and I knew I had a long day ahead of me. Any way. No I do not know where the IC is at but will know tomorrow afternoon when I get it back from the shop. Also no I do not have any digital video at the moment. My computer and cam-corder were stolen shortly after we got home from Badenton. All though on the home page of the NMRA. click the Bradenton link and the NMRA TV link. I am the 4th race in the Sun Elim 1 OC MM. I will have current video after this weekend. P.S. I am also installing a upper control arm bracket to change my uca mounting location and pivot points. This should get my CI closer to the rear end where ever it is now.

[KEVINS]

What bracket are you buying to change the IC? Don't use the one from Jeggs b/c this creates major binding. Make sure the UCA's still have freedom to move in all directions..

Good Luck..
ks

[Redsnk95]

Hmm...have me worried with my 150lb springs in the rear.

Troy

[jericoholic]

Hmm...have me worried with my 150lb springs in the rear.

Troy
You should be. 110# ;)

[scstang377]

What are the best brackets to change the IC and were do you get them? Thanks.

[rockinjester]

ask Kevin. He makes the kit. Check out his web site mailto:Tech@baselinesuspensions.com Good luck.

[blake_yount]

If those are the Moroso trick springs take them off and throw them in the trash. Put some stock springs back in it. I have an outlaw EZ street car and my car was doing the same thing that you are describing and I changed the whole rear suspension. Just picked the car up from Team Z and haven't made any passes yet. Call Dave Zimmerman he can hook you up!! Literally!