halokiller

Hello,

Ive been out to the track with my 03 hci c5z a couple of times and have been disappointed by my 60' times. Im running 275/40/17 MT drag radials. The best I have been able to do is 1.75 60' with a 3500 clutch slip. If I do a launch at a higher rpm, I spin the tires. I have been doing 1st gear burnouts as well because I bog the car when I try 2nd. I might try 2nd gear next time and be release the clutch quicker. I have an aftermarket clutch and run the tires at 15psi.

What kind of 60's should I expect with these tires? I was hoping to get into the 1.6's. Is there a trick to get these to launch better?

Thanks

98NYFINESTVETTE

I have used the same tires on an automatic running 11.50 with a 18.5psi. Leaving the line at 2,400rpm's. I understand you have a stick, what gears in the rear? You may have to bog it depending on the gears. I have 1.60's sixty foots. Good luck

How where the track conditions? Where you in the groove?

robz

Yes.
What clutch are you running?
You don't want to launch in 2nd gear.
15 psi is as low as you want to go with that tire. I'd probably start around 15-16psi cold.
I'm guessing you might not be getting the tires hot enough or your definition of a slip is closer to a dump. If you have an on/off type clutch it will be harder to but there is no reason you can't 60' in the 1.5x's on a good track surface. I'm sure you know gears will help as well. Check out technique below.

Tips:
-Make sure you are in the groove and shallow staged.
-Try doing a big smoky burnout to make sure the tires are hot since you are spinning badly
-Take note of your launch rpm, ignore the tree, and try and launch the same way each time and only alter your launch rpm by 100-200rpms at a time.
- Get very familiar with the clutch pedal release point. When staging, light the bulbs at that breaking point and slightly depress the clutch another 1/2" or so, so that you are off the floor but just below the engagement. As you rev the throttle to launch at desired rpm, stop and hold it there for a second or 2, try riding the clutch out at the same timing and pace you feed the throttle. This way you are right at the clutch threshold and not "hitting" the clutch so hard which will tend to invoke wheelspin. It's like bunching a heavy bag when you fist is only a few inches away from it.
Sometimes you want this wheelspin/wheelspeed but for your purposes with this radial setup, I'd work on reducing it.
You may find you can launch much higher this way than if you had the clutch on the floor. Also you may notice that the car creeps somewhat on these type of launches which you don't want but at least it tells you that your close and that's where the practice comes in. If you had a stock clutch or if you had a bias ply tire you could launch much differently.
It's best to learn on slicks or et streets and you'll likely have a lot more fun launching but if this setup is your only option then try some of the stuff mentioned above.
-Smoother is better.

halokiller

Thanks for the response,

I meant 2nd gear as in a 2nd gear burnout. I think my clutch release might not be as smooth as it should be. I was afraid of burning up the clutch. This is what makes drag racing fun for me. I know the tires are more than capable of better 60's, I just have to utilize them correctly. I bought the car used so I don't know what clutch is in it, but it does have a short disengagement range.

robz

Cool. Either gear burnout. Try things out and let us know. It will take practice but creep up on it.
And do the Ranger clutch fluid flush regularly.

dankhts

same tires/size here, but with an A4 and 3600 stall.... can cut 1.5X 60' without spinning at 18 - 19 PSI, flash the stall to about 1500 ish RPM at the line - sounds like you need a bit more burnout to prevent spinning...

skull

the radial will need good prep to. my track hooked as good as some of the best in the country. I have my intake, exhaust and 3.90 gears c5z on 275 40 17 e.t. streets and was leaving at 6k. best I pulled was a 1.53 60ft. had about 18psi in them