oadamo

iTrader: (1)

hi what revs do people use when launching and do you let the clutch out fast or just pop it out. whats best.
adam

Skooby53

iTrader: (1)

Hi Adam, holding around 4k is about as far as I would go and that will scare you, honest! I really would not recommend this though, the stresses that this places on the transmission etc is going to kill something. This type of abuse will find your weakest link and it will eventually go bang. Try and get a slight rolling start if you can as this will reduce the stress. Doing a rolling start you can just side step the clutch and go, don't slip it or it will burn out eventually.

drewruberry

iTrader: (2)

im running around 350bhp and at santa pod i do full 5500rpm launches. Its alot of fun but does put lots of stress on the transmission but im still on standard box and diff and its holding up ok. I just hold it at 5500 and then let the clutch out fully

oadamo

iTrader: (1)

ive tryed holding the revs and letting the clutch out fast but i nearly fryed it lol. i was going to pop it out but my gearbox is not the best at the mo ive heard a lot about ppg boxes so iam looking around to upgrade. ill still have a go tho and see what happens. does the diff let go aswell or just the gearbox.
adam

WaltonWRX

iTrader: (4)

My tip is ingauge the clutch as quickly and poss, I whip my foot of the pedal.... less slipping and less smell after

RyanSTI

iTrader: (1)

i maxed out at santa pod the other month, ran a great run but ripped the mounts in half.

Jeem

iTrader: (1)

I let the clutch bite while my foot is on the brake and reving it to bout 5000rpm then pop the clutch and give it full throttle when the lights green.

Andy T

Personally use the handbrake to hold car, bring revs to about 4k, bring clutch up slowly to bite point. The idea of this is to pre-load the transmission to reduce initial damage and possible shear forces. Dont hold here for too long, but you will feel the car load up, then in one swift move drop handbrake give full throttle and release clutch as quick as possible.

Running a fairly standard box/transmission with an exedy clutch, find this method will light the tyres up quite easily. Just have a bit of mechanical sympathy as it is not nice when a box decideds to injest itself!!

debbiesonic

iTrader: (7)

Andy T, i'm curious to know what tyres you're using?

We went along to the local strip the other week, (hubby drag races a bike in straightliners pro-street class), he has often talked about taking the car on just for a bit of fun, and as it was a rwyb meet we were expecting it to be rather quiet so we took the oppertunity.
The reason i ask is, it just would not spin the tyres off the line no matter what. First couple of runs were sympathetic launches and on the verge of bogging. After that i thought he was trying to kill it! Full throttle, sidestepping the clutch, it would give a slight chirp (and i mean slight chirp) of the tyres, before sqautting and propelling itself like a rocket. Looks fantastic on the video the way it takes off.
He's used to his tyre still spinning 3/4 way up the track, so he was surprised by the traction it got. He actually said. he felt more G when the car was launching than he gets on the bike.
The cars not underpowered btw. It's a purpose built track car, stripped and caged, RR'd @ 381/347, exedy clutch, Yoko parada spec 2 tyres on the day.

I've read a few posts about people 'lighting their tyres up', i think they must be under rating the power they have

Andy T

Debbiesonic, the tyres i am using at the moment are really nothing special, but my favorite budget Nangkang ditchfinders until I am happy with my suspension/geometry setup experiments. As you know the drag strip will often have a higher grip surface than the average road, except for the patches of high grip tarmac near junctions/traffic lights, agree theses areas I struggle to get any slipage. HTH

JB1

Debbiesonic, Andy T. I use the handbrake too for holding on the line. But I have launch, which holds at 6500, then just dump the clutch. We found that anything less than that it bogged down a bit.
It doesn't spin the wheels though even with a manual launch. Unless you are almost bouncing it off the limiter, in which case you more or less stand still while it makes lots of noise.

Julio Jordio

I used to have a CTR before the Scoob, and that was forever lighting its front tyres, especially if it was wet/damp. Not just from a launch, but say set off in first, and I was to give it some, it'd be moving slowly but just spinning the tyres. That was a 200 bhp car, my Scoob is 317 bhp and as above, short of a 5500 rpm launch, I havent had my tyres chirping from a launch once!

I am running GF1's.

ScaldedCat

I normally slip the clutch at a RYWB, but last time at Santa Pod the other week decided on a 4000rpm clutch dump.

Two things happened:

1. I knackered my clutch
2. I got my fastest time ever!

Once clutch is replaced, I'll try Andy T's method.

rooferman

iTrader: (6)

Just bear in mind those who have dccd in a classic that holding the handbrake will set the dccd to diff free mode.......

WUZ

iTrader: (14)

..................... unless you rig in a switch on the wiring that detects the handbrake is applied so you can disable that issue.

Russell

ChristianR

iTrader: (1)

you can see how i launch here :

CICarScene.com - Rally Sprint Jersey - L'Etacq Attack 12th July 2008 Stage 4

dougwrx

Imho you should never slip the clutch or feed it in, I get to the line and rev the car up not holding revs and I dump the clutch fully at about 6000rpms or higher and away we go. I did 50 runs at this years Scooby shootout and I had 30 runs in the 1.6 60ft bracket with a best 1.61 on road tyres. I did it this way when my gearbox was standard with 330/330 and still now with ppg with 500/500 I have never damaged a clutch dragracing with this method but I did snap a rear driveshaft in two the other week .

Cheers Dougie

terzo320

i was at santa pod a few weeks ago 5 to 6k revs and dump the clutch works well

mickywrx

iTrader: (29)

Give it death, and dump the clutch works for me.

Death being anywhere from 4.5>6.5k

Jeem

iTrader: (1)

Got a vid of me launching as discribed in post 7 https://www.scoobynet.com/scotland-2...-fao-jeem.html

smokingkills

iTrader: (3)

one of me cheating with launch control set at 4500 revs YouTube - Smeatharpe July 08 1/8th mile drag strip. Subaru WRX STI V Subaru WRX STI

jd5217

I recognise the car in the opposite lane.

morpheus1870

Sweet driving mate, damm good job!!!