This was my best time that night and happen to be filming in the car at the time, but unfortunately the camera went dead right after take off. I had a sticking thermostat that night (replaced now) and I'm sure I was running way rich. I launched from about idle.
I tried several RPMs, but they all were slower than this. YES, I know it's slow, but the juice is on the way, so for now, I'd like to learn to be a better driver.
Well, with my eco I rev up to about 3000 rpms and feather the clutch some when I launch. That seems to work the best with my car.
you spun and then bogged..
so I'm going to say too low an RPM, and too much clutch
rev to 4000, keep the revs high let the clutch out sharp, but at the same time feather it to keep the tires on the brink of spin
once you feel the car is gripping hammer the throttle and let the clutch all the way out
Thanks. Sounds like a launch that takes a lot of practice to get just right.
Yes feathering the clutch takes lots of practice (I can't do it). I launch at 3000-3500 RPM and just let the clutch go. To me in the video you did not launch at idle, sounds like it was reved up a little. What was your tire pressure at?
FU Tuning
^^
At about 1500 at launch, tire pressure was street pressure (35). I know 25 psi would've been better, but I'm trying to work out one variable at a time.
I think if I can get a better launch, lower my tire pressure, and not bog it I can run a 2.3. Then comes spray and Eagle rods.
David St. Hubbins , AKA: Eddie wrote:^^
At about 1500 at launch, tire pressure was street pressure (35). I know 25 psi would've been better, but I'm trying to work out one variable at a time.
I think if I can get a better launch, lower my tire pressure, and not bog it I can run a 2.3. Then comes spray and Eagle rods.
You can't just work 1 variable. they all work together. 25psi is not a best pressure. It will be different for all. I usually recommend starting around 28psi and launch at the same RPM. If it spins lower the pressure another pound or 2. Do the same way again. If it bogs then you can up your RPM by a couple hunderd and go again. Keep ding that until you get the highest RPM you can launch at with little to no tire spin. A little bit a chirping is ok, but NO wheel hop!!
FU Tuning
John Higgins wrote:David St. Hubbins , AKA: Eddie wrote:^^
At about 1500 at launch, tire pressure was street pressure (35). I know 25 psi would've been better, but I'm trying to work out one variable at a time.
I think if I can get a better launch, lower my tire pressure, and not bog it I can run a 2.3. Then comes spray and Eagle rods.
You can't just work 1 variable. they all work together. 25psi is not a best pressure. It will be different for all. I usually recommend starting around 28psi and launch at the same RPM. If it spins lower the pressure another pound or 2. Do the same way again. If it bogs then you can up your RPM by a couple hunderd and go again. Keep ding that until you get the highest RPM you can launch at with little to no tire spin. A little bit a chirping is ok, but NO wheel hop!!
Wouldn't I be working one variable if I do that with my tire pressure. lol
I am trying to figure that out myself. I took my sunfire to the track for the first time this weekend and had a bad problem with wheel hop. I was launching at 3000rpm and popping the clutch. The tires were hooking without any wheel spin since the tires are 225's and plenty of VHT on the track. But the wheel hop was killing me.
see my post here
http://www.j-body.org/forums/read.php?f=48&i=20946&t=20946 thats my technique, it has been passed on to me by the 1.8T gods but should work for pretty much anybody. Of course, if you're running different tires, disregard the part about pressure and burnout, you'll have to figure that part out for yourself.
Arrival Blue 04 LS Sport
Eco
Turbo
Megasquirt
'Nuff said
Thanks, read it before but forgot seeing it. Will try that some next time. ^^^
Jon Simmons wrote:I am trying to figure that out myself. I took my sunfire to the track for the first time this weekend and had a bad problem with wheel hop. I was launching at 3000rpm and popping the clutch. The tires were hooking without any wheel spin since the tires are 225's and plenty of VHT on the track. But the wheel hop was killing me.
If you have wheel hop you are not hooking. What was your tire pressure?
FU Tuning
35.
That 2200's got a rod knocking now, though, so down until I get this Eco swap done, Next time I'll lower the pressure to about 28 and try to feather the clutch a little more. Going to expect a big improvement anyway with about 30 more hp with the Ecotec.
