Ok so I'm pretty damn frustrated with this. I cannot find the right amount of boost and the proper RPM to launch at. Below is everything I have

Engine:

* Harrop 1320LSJ Supercharger 80MM pulley
* LS4 77mm Throttle Body
* Rebel Auto Worx LS4 Throttle Body Adapter plate with 1/8NPT tap for water injection nozzle
* Quaife Limited Slip Differential
* GM Performance Parts Dual Pass Option B kit
* HP Tuners Tuning Software
* OTTP Rotated Mounts
* Fujita F5 Intake
* CX Racing Heat Exchanger
* ZZP Midlength Header Ceramic Coated
* ZZP 304 Stainless 3 inch downpipe with Magnaflow High Flow Cat
* ZZP 3inch Whisper Catback Exhaust System
* AEM Water Methanol Injection Kit
* Siemens 660cc Injectors


I cannot for the life of me get it right. I either shoot into boost and then bounce off the limiter because it blows through the rpms too fast or it bogs because theres not enough boost or not enough rpm.

whats a good percentage and rpm to run, or at least something to start at nothing Im doing is working

 

What happens at around 3.5k to 4k?

 

avoid the water box when on street tires, drop tire pressure to a happy medium, leave off idle and gently roll into throttle. You have limited boost no?

 

3.5-4k should be a good RPM with a little bit of clutch slippage.

 

Yeah if so just let off the throttle till you catch grip then ease it through 1st and hammer 2nd

 

yea right now the boost cut is kinda funky because of the LS4, I have zero boost to 4000rpm so its not all jerky and then the boost ramps in to 100% by 5500 or so

Yesterday I tried a 4000 rpm launch, nice tire spin with no wheel hop the rotated mounts are doing what they are supposed to and it really jumps through the rpms as soon as the boost hits so its hard not to hit the rev limiter in first

 

Slip the clutch some.

 

so let it out slower rather than dumping it?

 

yeah, or feather the gas until u catch a decent grip instead of spinning into your boost areas

 

Dumping the clutch is never the fastest way off the line.

 

i have no problems launching my **** , maybe you need some good tires. i have no boost cut and i also dont have a ls4 tb

 

2,000 rpm. street tires at 24psi. slip the clutch out of the hole. got me a 2.1 60 foot on stock tires

 

With the LS4 its very hard to have a smooth and gradual engagement of anything in 1st gear. I have some somewhat worn stock contis on my 08-09 SS wheels if that means anything. They do grip way better than the redline 17s with brand new 225/45 Yokahoma S-Drives, I spin the **** out of those.

 

get some dr's or slicks im selling some bfg dr's 225-45-17 for 200 almost brandnew

 

realllllllly how much shipped to 17111?

 

You can't dump the clutch. If you have no boost until 4k then you should be able to hold the revs at 4 k, slip the clutch till the car catches up till about 4k then WOT. By then you will probably be leaving the 60' area and tire spin isn't a huge issue. I ALWAYS spin 1st a the track but it doesn't spot me from 60footing or launching well. I also find that if first is spinning ride it out of the rev limit for a second so that when you shift to second you don't bog.

 

Most FWD drag racers will tell you a very little bit of spin helps get the car moving.

 

heres me last night on STREET tires out launching an a4 ls1

https://www.cobaltss.net/forums/war-stories-54/few-suprising-races-tonight-173574/

more practice muh friend

 

thats impressive

 

bring R's to 2K let clutch out until it engages a TINY bit then go 1/2 to 3/4 throttle(depending on conditions) while slipping the clutch by 2.5-3K you should be WOT tires sticking....

 

go buy some real tires. Trying to launch hard on street tires is just dumb. and pointless.