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Author Topic:   Too loose on dry slick
Morpheus
Dirt Newbie

Total posts: 2
posted July 15, 2002 02:55 AM
I've got a street stock camaro and I can run ok on a wet track, but when the track becomes dry slick my car gets way too loose. I'm hoping someone can help tell me what I can do to tighten my car up for a feature race. I'm on a 1/4 mile flat track with 7.20 final. Here is some info:

Springs
LF-1000 RF-1400
LR-225 RR-200

Shocks 50/50 all around

adjustable weight jack on RF

51.5% rear
52.9% left
42.1% cross (just recently bought this car and I've read that I should want to get it to at least 49%...need input please)

air pressures
heat race LF-10 RF-13
LR-12 RR-13
feature LF-10 RF-13
LR-13 RR-13

Tires are same size and offset all around

car total weight is 3300 with driver

Sometimes the car does push a little but I think that's because the crossweight is too low. Hopefully bringing it up will help that.

Can I tighten the car up by just adjusting air pressures or would I need to change some spring rates? I set up early for the turns and I'm sliding so much I just can't stay as low as I'd like and the rear of the car just feels like it wants to come around more than I'd like it to. I can pedal the gas around the turn but I'm losing time and getting passed doing this. PLEASE HELP!

BGA
Dirt Roller

Total posts: 16
posted July 15, 2002 07:20 AM
just off the top of my head I would say more
cross weight should help. Please do not make the assumption that I am by any means a chassis specialist,cause I am not. I do know that my car did the same thing and the cross helped out a lot.
Bruce

tyler weiss
Dirt Roller

Total posts: 13
posted July 15, 2002 10:32 AM
Instead of changing your percentages all you have to do is put a tire with less back space on the left rear this will make the car just a little bit tighter. I had the same problem last week.

driver27
Dirt Full Roller

Total posts: 69
posted July 15, 2002 12:46 PM
Forget playing with tire pressure and wheel offset at this point, they simply do not make the magnitude of change that you need. Get the car on scales and get the cross up to 49 - 51% if the track really gets slick. Only way to get that much cross is take lowering block out of the left rear (at least one inch less than right rear) and add a couple turns to the right front. Once it is close, then play with offset and tire pressure. Those two things generally only change wheel weights about 20 or so pounds each, so they are fine tuning tools. Try it , you will like it I promise.

Morpheus
Dirt Newbie

Total posts: 2
posted July 15, 2002 05:45 PM
I appreciate all the information. Keep the replies coming!! It'll be Thursday before I can get this thing back on the scales and have the time to work with it. I'm new to the forum and have to say that I think it's fantastic. I wish I had found it sooner.

mtwrght29
Dirt Full Roller

Total posts: 32
posted July 15, 2002 08:20 PM
first of all i agree with the advice of driver 27. but i have a couple of more suggestions try a 1200 lbs. spring in the right front 400 lbs. split is too much. secondly unless you are way over minimum weight add more lead to rear. 52.9 rear percentage is ok on a tacky track but you will get more rear bite with more like 54-55 percent rear weight i wouldn't go over this though or you may get loose again due to pendilum effect

millerlt3
Dirt Forum Racer

Total posts: 96
posted July 15, 2002 11:03 PM
man with 42.1% cross your lucky to even get the thing to turn into the corner. 49%-51% depending on track conditions and driving style is a good starting point.

Scoot
Dirt Freak

Total posts: 330
posted July 16, 2002 12:39 AM
In my opinion, which is not worth much. I would try zero stagger and try alot lower air pressure in the lr like 8 or 9lbs. You can also try a bigger lr if the above doesnt work. These changes can be made without much hassle. Hope this helps.

------------------
Scoot
Smith Racing Team
870-365-5989

powerglides
Dirt Full Roller

Total posts: 69
posted July 16, 2002 06:25 AM
Driver and Miller are right lets get the cross weight close to 50% before anything else. then start playing!

driver27
Dirt Full Roller

Total posts: 69
posted July 16, 2002 08:47 AM
yep, once you get the cross weight in the ballpark, then you may find that the front split is indeed too much, i missed that detail, good call. A 1200 on the rf should be about perfect. There are other tricks to help with forward bite on leaf springs , but get the basics right before we discuss that. 42% cross, yeah I bet that was a wild ride, you should get better wear out of the rr tire when this is all done too. What kind of tires are you running?

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