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MO_chevelle

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Im going too the track this weekend with my 69. Stock front suspension. SSM lift bars in rear. 400hp/425tq TH 400 tranny 3000 stall. 235/70/15 regular tires. Im looking for any advice that may help me, something you wish you would have known when you raced for the first time. Im going too unhook my swaybar, I assume I should unhook my vacuum advance, Im planning on making it idle at 1000-1200 so I launch the same everytime or should I try too make it stall as much as possible without turning the tires? Any suggestions on tire pressure. Im pretty sure traction will be a problem but I dont want too spend money on tires until I see what Ive got. Any help will be greatly appreciated.
 
Don't power brake it at the line, leave off a 1200 idle. Don't bother disconnecting the sway bar it won't matter with your street tires. Your vacuum advance shouldn't matter, over 3000 it should be all in anyway with the mechanical advance.

Run your standard tire pressure in your radials, maybe 28 psi min. Any less and you will not get good contact with the center of your tire. Do not do a burnout, it will make it worse with street radials, drive around the water being careful not to get any water on your tires. Watch a bunch of runs before you go up, see what the sequence of events is like and be careful not to stage with your rear tires, happens a lot to first timers.

If something doesn't seem right like you broke something, pull over to the edge of the track immediately and stop, the last thing you want is to spill something all the way down the track.

Hope this helps and many more will respond with other tips,

Have a blast
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I agree with everything Tom said. Unhooking the sway bar won't help much, and there is no vacuum advance under full throttle (vacuum falls to zero at WOT). My experience on street radials is they always work best at high pressures, 32-36 pounds, for the reasons Tom described. With a 3000 stall, going instantly to full throttle will blow the tires away. You will have to learn to get the car rolling and ease into full throttle. It's very frustrating, and takes lots of practice.
 
On the radial tires, I dropped the PSI from 28 to 18 and my 60 ft time improved. I'll do the same next time I hit the track.

Watch the guy starting line guy(s). They'll guide you into place and tell you when to do a burnout (if you're not running radials) and when to stage. Don't worry about what the guy in the other lane is doing. Concentrate on what you need to do to stage and get down the 1/4 mile.

Try different things to improve your launch. More throttle, less throttle, more power brake, etc. Once you make a few passes, you'll get the urge to experiment. Most of all, have fun!
 
Mark,
I'll be looking forward to meeting you. My son and I will be there all 3 days as we live close by. Just look for the fat guy w/ the cigar and a brown Chevelle. Here's the web add to a pic of my car on my brothers web site. Couldn't get the link to work. Gary
http://scarecrw28.freeservers.com/index.html
PS Got the car all legal for the track? George is a very picky inspector.
Don't know how but the link works now!
 
some things i dont agree with is the radial tire comments.....i have been running radials since the day i started racing since early 1990 and i want to say that each and every set of tires i have bought new or used responded the BEST with less air pressure and a hotter burn out....

in the beggining i took the advice full inflation and no burn out only to be handed over crappy 60 ft times......

thru experience i have devoloped my own way to set air pressure for each given car....radials with the stated air pressure amount on the side walls are to round....meaning the outer edges of the tires just dont get to see the cement and therefor you are giving away tread contact area that you can be using for traction....

best thing to do.....wet your driveway (small area) for your tires and roll the car thru the water.....(rear tires only) and look for yourself how much tread is not hitting the ground...now lower the air pressure till you achieve the most contact across the tire.....now dont go to far to where the middle of the tire is fading out.......

in most cases with a 60 series tire you will be in the 18 to 24 psi range depending how much weight the rear tires are taking on......

now you have a base line that is close.....the nest step is to do a little burn out about 12" long and check you burn out patch what you are looking for is a nice even tread wear pattern not to dark on the edges or to light in the middle.......temp gun would be nice to check the temp across the tire...now this is where you can make your final air adjustments....may take a few times but you will find the sweet spot......even tread color from the burn out.....

once this is done you have the best traction patch possable from your tires......now the burn out will depend some for each track......in most cases doing a burn out with radials in first gear and second gear lift the brake and ride it to the line under power......brake intime to stop for the stage lights and stage....NO dry hops.....

now i know this works for i have run the 60 ft time so far on radial with a 1.72 60 ft....with the sidewalls of the radial wrinkled on the start line........the tires i used was bfg 275/60-15 with 18 lbs of air pressure and they was used from becker tires for 10 bucks each... on my 81 camaro running 12.18 @ 110 mph in street trim....

right now im running 245/60 -15 tires uniroyals that are sticking at the track under full throttle from 1400 rpms stage. with 104 plus mph trap speeds....tire pressure for these tires wanted to be set at 22 psi and best traction is acheived with what was said above.......

with street tires you want to stay off the convertor for this tightens up the suspension and just makes the rear tires spin......allowing the car to go thru its motion help in planting the tires......

being this is your first outing i would just work on in trying to launch the car......get the tires set up as described above and go at the track with ease......maybe first time up there on the line do a small burn out stage the car and hit part throttle and see how it grabs......get alittle more agressive each time.......you will find the limits of your traction you will be able to "feel" it when your just about ready to break loose .......unless im the only one who can....lol.......
 
Lug nut on every lug.
Battery is secure.
No more than than 12" of rubber fuel line, total.
Radiator overflow.
Seatbelt.
Operational neutral safety switch.
Helmet, driveshaft loop: don't remember the limit for these with street tires.
No big holes in firewall.

Staging with the rear tires is a big one.
Walk up to the starting line as close as they will let you and look for the staging beams, and closely watch a few people stage.
 
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Originally posted by Lonnie67:
Lug nut on every lug.
Battery is secure.
No more than than 12" of rubber fuel line, total.
Radiator overflow.
Seatbelt.
Operational neutral safety switch.
Helmet, driveshaft loop: don't remember the limit for these with street tires.
No big holes in firewall.

Staging with the rear tires is a big one.
Walk up to the starting line as close as they will let you and look for the staging beams, and closely watch a few people stage.
Right on! Double carb spring, too!
 
Tom,
you're style obviously works well for you, and probably for a street tired car as well.
But my question, is to why you do this instead of loading the converter.

When loading the converter you are tightening up on the driveline, taking the slack out of the ring and pinion, and all other gearsets, as well as loading the suspension.
Making for quicker reaction and 60ft times.

I would think it would be easier on the driveline to "hit" a loaded suspension, rather then take up all the slack upon the initial hit.
 
Yeah, I know Brian, it would seem so, but I have tried it and tried it with every combination and whenever I load the suspension...Tire Spin :( .

When I launch at 1200 there is some degree of pre-load in the driveline taking up some slack. I would love to try a transbrake for a dozen passes or so, but that would be it.

out of 84 passes so far this year, I have only lost traction 1 time and this was after the evening dew dropped from the heavens and ruined my final round race.


ddennis - hats off to your technique and I have to admit I expected to read as I made my down your write up that you were talking about drag radials. I have never witnessed a street radial work as well as you have described and never heard of any either. but hey !! $10 tires
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They run a true radial class at the monthly shootouts at our track and some of those guys are down in the mid 1.5x's 60ft. times. running mid 6's in the 1/8th. Of course they treat them with their "secret sauce" of choice...still impressive,and making lots of hp.
 
i too have found out when running just plain radials that over loading the suspension just creates tire spin...... even thou bringing the car up on the convertor allows for better reactions times.....it really hurts the 60 ft times on street radials...the car needs the motion of the "weight transfer" to help them hook.....if you take that motion away they just spin......

like tom said you do have slack taken up even with the lower launch rpm.....but there is still enough movement left in the chassis to allow everythig else to happen......

now when racing with slicks and using nitrous off the line like i do with my real race car....yes it is best to fully load the convertor and take all the slack out so parts dont break......

there is that line between having enough traction to not to worry about blowing the tires off and trying to get away with street tires that limit the load of the launch......its just one of those things you cant treat a street radial like a slick so you have to find other ways around the traction issue......

tom.....i would imagine im the only idiot that has spent more time with tunning street radials......to me slicks are an easy out for traction.....i find more fun into trying to get the chassis right to run street tires....besides isnt that what most street cars run on...lol...so why not tune the chassis to make it work with radials......i know i dont have time before the light turns green to change to slicks for some stop light action.....lol
 
some use wd-40, some use brake fluid, mixed with vht and wrap them in plastic til they are ready to use them. It softens the rubber so they hook almost as well as slicks. Which way off the 208 Paddy? north? A friend of mine used to go there quite regularly with his 60 Biscayne, I've heard they are real strict with their tech?? I'm sure I could pass,but that sure is a long tow :(
 
Tom,
Is this true with True slicks, or just the Quick Time Pro's?
I'll switch to Quick time pro's next season to get back to my regular racing class, but for right now i'm enjoying the use of Hoosier CO7 compound slicks.
Always looking to learn. :D
 
My car consistently 60's in the low 1.60's with a best of 1.59. I set my idle up to around 11-1200 and mash it and get my best 60's. I tried loading the converter and the best 60 foot I could do was a 1.74 loading the converter to about 2300. I kept lowering my leave rpm and eventually got my best 60' leaving off an idle. This is with 28x10.50 in MT ET Drags Stiff Sidewall. I thought the same thing that it would 60 better loading the converter but it doesn't for some reason. Just thought I'd share what my car does.

Matt
 
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