Proper way to launch a manual?

[Zevox]

Okay so all these broken rear end threads have me a little spooked. Going to hit the track tomorrow and I feel like my car living through it so looking for advice. Is there a good way to launch a manual hard enough to cut a decent time but easy enough that the rear end won't fly to pieces?

I'm running Mickey ET Street radials with the Torsen locker and 3.73's and last time I was out at the track I was dumping the clutch at around 4000-4500rpm's. I launched low a few times and bogged which feels really bad on the car. My car just got the rest of it's suspension on and Kelly@BMR said I should be able to dump it at 6k and cut a sick 60ft time but... that sounds dangerous to my car after seeing all these threads, haha.

I'm low on the horsepower spectrum if that changes things, just running a FRPP tune, CAI, and catback exhaust.

 

[debit_free_2010]

I wouldn't suggest any 6000rpm clutch dumps unless you have a way home.

Since you're on ET Street's, Start with higher tire pressure (20psi if the track is prepped at all) and launch at say, 4500, and if your spinning work the pressure down till you hook.

To keep the slop out of the drivetrain while staging I roll into the light and use the emergency brake to stop. That helps prevent drive line shock when you drop the clutch.

Try to be smooth on the clutch release as you slam your foot to floor, bogging isn't bad on the car, it tells you either need more tire pressure or launch harder.

I like to run as much pressure as I can and launch softer than use lower pressure and leave harder. It it can get rather exciting to launch at 6500 on slicks and have them dead hook at 12lbs.

It'll take some trial and error to get it figured out.

 

[ExTurbo]

I was always ok with 1.7's and knowing I had a few 10ths left in her, kept pressure a little higher so it spun a little (on a slick) when I had my Gto. Always worried about breaking something. I know I could launch harder but I was too afraid to break my daily driver lol. Guess if I had a backup plan it would be different.

Also what debit said about keeping the slack out of the drive line makes a difference, try letting out of the clutch until just before it engages and lift your foot off rather than dumping it from the firewall

 

[cobrakidz]

The quickest way to find the weak link in your drivetrain is by dumping the clutch.

 

[wikdlx]

you need a 2 step and a line lock on the same button on the shifter. this way you can leave with the gas on the floor and just let off the button...............this has always worked best for me

 

[Zevox]

Thanks for the tips everyone. Didn't make it out to the track today but I might try for tomorrow if the weather holds out.

 

[Stormtrooper5.0]

Also been wondering about this because this has been my biggest trouble with getting a good 1/4 time. All of my problems seem to happen in the first 330. Either bogging or spinning off of the line due to a bad launch or spinning after the 1st-2nd shift.

 

[agony]

Shouldn't he be able to use the adj suspension to take some of the shock off drivetrain to hopefully not break the rear?

The reason I ask is that I will be having almost the exact setup (after I order my strange/vikings).

 

[blackbeast12]

Torsen diffs are not for drag racing eventually it will break on you, even sooner then a non torsen rear. Buy a Ford 9 inch then all you will break is suspension parts!

 

[5lho]

In my search for 11 sec 1/4 I tried every launch rpm from 3500 to 6000, full dumps on every one. Now, I'm on a 28 inch bias slick and the carbon clutch LSD so I could get away with that.

Found the best idea on 3.73s and a stick is to put about 4500 on the clock, let the clutch out to engagement and dump and stab at the same time. The car likes to eat in first gear a bit. The 60s were no quicker launching higher.