Suspension, Tires, or both?

[dville_gt]

Went out to K-dale yesterday and could not hook at all, this was at a measly 5lbs as well. Car danced all over the place and I had to go in and out of the throttle all the way down (was sure I was going to take a timing marker out on my 2nd pass). So now I've got to get this figured out, that was only on 5psi, I put a 10lb spring in today and it'll blow the tires off rolling into the throttle in 3rd (top gear), it feels about 10x more powerful at this setting and it wouldn't even hook on the 5lb spring.

Anyway, the tires are 28x11.50x15 et street bias plys. I have a set of et street radials that I am going to throw on, but I'd imagine they will be even worse since they are a radial. On the other hand the bias ply's that are on there came with the roller and could be 4-5 years old, and I've personally put 1800 miles on them so they are not in there prime either.

My suspension consists of a coilover fronts (I believe they are 150lb 14in springs) w/lakewood 90/10's. The rear has strange 10-ways (set on 3), stock v8 springs, and a Wolfe anti-roll bar (first time out with it). Of course all the control arms are tubular front and rear.

I made the passes yesterday w/11-12psi of air in the tires (which is right where I normally run them). I don't know how everyone else was hooking, but I know they were some of the most concerning passes I've ever made and I won't be back out till I change something.

Any suggestions, I guess I should try the tires first since thats the easiest/cheapest. How are you guys setting up your anti-roll? I tried to follow Wolfe's instructions for mine but don't know how accurate it is since I pulled the link and had to put it back in without resetting everything.

[shumpertdavid]

+1 for new tires. The m/t drag radials are pretty impressive, if the 10.5 guys can make them stick you should be able to also. Same advice was given to foxbody mike when he was complaining he couldn't get his old dried out slicks to hold.

[LS1Goat]

Went out to K-dale yesterday and could not hook at all, this was at a measly 5lbs as well. Car danced all over the place and I had to go in and out of the throttle all the way down (was sure I was going to take a timing marker out on my 2nd pass). So now I've got to get this figured out, that was only on 5psi, I put a 10lb spring in today and it'll blow the tires off rolling into the throttle in 3rd (top gear), it feels about 10x more powerful at this setting and it wouldn't even hook on the 5lb spring.

Anyway, the tires are 28x11.50x15 et street bias plys.

Something is definitely a miss. I had to put in hotchkis control arms and weld up the torque boxes because my 28x11.5 e.t. streets were trying to rip the car apart. About 10 psi on a prepped track and it's like tires were welded to the track.

On my Nitto DRs, you could spin through the gears to 330 ft. mark. Total junk.

[Super Coupe]

It's probably the tires. Even foxbodymike spins his old dry rotted slicks.

[Chas_svo]

Everyone is probably right on the tires. Do you have a video? If you do, slow it down and watch tires, suspension, etc. It's very enlightening.

Good luck.

[dville_gt]

no video, i'm going to swap out the tires and see how it goes. the car felt all over the track. the odd part is that it still 60'd 1.5's, just felt loose when it got into boost. now that i've turned it up it blows the tires off at ease in any gear.

[CYAZ06]

I noticed there was no mention of a torque arm or panhard bar? What kind of RWHTQ are you laying down?

[dville_gt]

I noticed there was no mention of a torque arm or panhard bar? What kind of RWHTQ are you laying down?

it has a wolfe anti-roll bar. i had the 5lb springs in so the tq shouldn't be too much, maybe 500ftlb

[Grape]

Get that thing on some scales with the swaybars neutral'd out

[dville_gt]

Get that thing on some scales with the swaybars neutral'd out

Where should I do this?

[Magnimike1]

The Radials should hook alot better if they are fresh and your car being an auto. Was it spinning right after 60', 330'? What do the logs read?

[dville_gt]

The Radials should hook alot better if they are fresh and your car being an auto. Was it spinning right after 60', 330'? What do the logs read?

Hard to read wheel spin with the logs, I am using a mechanical pulse generator to feed the PCM vehicle speed and it is kind of jumpy. I know I can see I was in and out of it the entire run. It is hard to explain but it wasn't like it was just blowing the tires off, it was just all over the track if that makes sense. I was trying to stay in it to get a good log, but I really shouldn't have as it did not feel safe. Maybe I let too much air out of the slicks or maybe they are just done, I'll figure that out when I swap them for the radials, but now that I've jumped up to a lot more boost I'm not sure how any of these "1000rwhp" cars can keep from skating down the road as my car makes way less and is blowing the tires off with ease.

[robert]

My .02
Try with newer rubber first at a prepped track with 13-15lbs (air)
then decide if your suspension needs tuning,
might need slight pinion angle adjustment. G/L

[G..]

Hard to read wheel spin with the logs, I am using a mechanical pulse generator to feed the PCM vehicle speed and it is kind of jumpy. I know I can see I was in and out of it the entire run. It is hard to explain but it wasn't like it was just blowing the tires off, it was just all over the track if that makes sense. I was trying to stay in it to get a good log, but I really shouldn't have as it did not feel safe. Maybe I let too much air out of the slicks or maybe they are just done, I'll figure that out when I swap them for the radials, but now that I've jumped up to a lot more boost I'm not sure how any of these "1000rwhp" cars can keep from skating down the road as my car makes way less and is blowing the tires off with ease.

ETstreet s will walk with that little of air in them. Try running them between 14-16. roll throught the water. Do a 2gear burn out. roll straight to the line and launch. That walk is normal for a street with low air. They are made to be run with alittle more air in them

[71chevellejohn]

Just a heads up -

If those are the same slicks that were on it when the roller was built then they are closer to 6 years old. Obviously they didn't have any usage, but the age is definitely there.