Sorry in advance if this is redundant. I could not find much in the search.

I understand that the key to a good, drive-line-friendly launch is getting the tires to slip. Up until this weekend I had some old Hoosier A3S04s on the AS car. I had that launch all figured out. With those old tires, I could rev up to 4500 rpm, slip the clutch a slight bit, get the rear tires slipping and get a perfect, easy launch.

I just switched to v710s with 265 width in the back, and now I can't figure out how to launch this thing without a) breaking the car and b) bogging badly. I knew I would probably need more RPM with the stickier tires. This weekend was my first try with the new tires. I had 6 runs and tried variations on launching at 5500-7000rpm, but I could not figure out how to get the rear tires to break traction. On 5 tries I bogged horribly. And 1 try I cooked up some yummy smelling clutch.

Any tips for launching an 00-03 AS car on the big v710s? FWIW the car has a huge Gendron front bar and stock shocks.

Andrew

 

Are you slipping the clutch quickly (sounds like it) or are you dumping it? If you are slipping it, there's your problem. From your description of burning a clutch I would say you are slipping it quickly. Rev it up too high and dump it. It should spin the tires. On the next run lower your rpms and try it again. You'll find the spot.

Also, the proper rpm differs thoughout the day as the launching surface gets chewed up and as track temps change. Every site is different too so it's really impossible to give an exact launch rpm.

Good luck.

 

[QUOTE=aklucsarits,Jul 10 2006, 11:42 AM]With those old tires, I could rev up to 4500 rpm, slip the clutch a slight bit, get the rear tires slipping and get a perfect, easy launch. I just switched to v710s with 265 width in the back, and now I can't figure out how to launch this thing without a) breaking the car and b) bogging badly. I knew I would probably need more RPM with the stickier tires. This weekend was my first try with the new tires. I had 6 runs and tried variations on launching at 5500-7000rpm, but I could not figure out how to get the rear tires to break traction. On 5 tries I bogged horribly. And 1 try I cooked up some yummy smelling clutch.[QUOTE]

I was launching at 7k rpm this weekend with great results. I tached up to 7k, dumped the clutch and floored it. Of course it varies greatly with the grip of the surface.

 

I guess what I was doing before (and what I was trying to do yesterday) was rev up to xxxx RPM, then engage the clutch maybe 80%, and then modulating the throttle to maintain wheelspin as I let out the rest of the clutch.

What is meant by "dumping the clutch"? Is that like side-stepping it? Or is it more like just releasing the clutch really quicky in one motion?

Thanks,
Andrew

 

Short answer---yes.

Personally, I release really quickly in one motion. Many prefer sidestepping as it is less likely to slip the clutch if you don't release it quickly enough.

 

sidestepping is the best way. With R compounds, sometimes the grip is higher than the initial bite of the clutch if the clutch is released the normal way, and the clutch slipping at 7000 RPMs leaves a nice smell in the car all day sidestepping is the way to go!

 

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ^^

Nice car.

 

She was a fine cah... the shocks were great on asphalt

 

Yeah just rev it up and cut it loose, slipping the clutch at all is a recipe for burning it up.

 

Agree with very fast or side step approach. Do it most events. I don't usually do this on concrete, usually just take off slowly and accelerate hard. All depends on the grip as mentioned above.