so whats better when launching droping the clutch or sliping it? what are the differences

 

When I drop it it usually does 1 of 2 things. 1 massive wheel hop or 2 way too much wheel spin. However I have a very aggressive clutch that will grip if I drop it from 7k. I find my best results are from slipping it but still spinning the tires.

 

which one puts more stress on the car? clutch tranny drivetrain so on.

 

Slip causes a lot of clutch surface wear. Drop puts a lot of load on clutch, tranny and drivetrain. If you're worried about those things then best option is to do neither most of the time. Save it for the ocassional drag strip run.

 

it just depends on your setup...

 

dropping does increase massive wheel hop, great for breaking traction for turning but bad for grip drag racing, or trying to get a good launch.

 

It depends on how much power and torque the engine makes, wheels, tires, suspension, alignment, etc. With NA's its best to drop the clutch at 5k+, TIIs you might be better off slipping it out. If you try it you will know when you have a good launch and when not, should have no bogging and minor wheelspin.

As far as whats bad for the car it also depends on the factors stated earlier. Stickier tires will transfer the stress on the next weak link the drivetrain during a clutch drop. Best way is to practice at a dragstrip and compare 60 foots.

 

I usually try to get staged first so I can watch the others staging lights as soon as his light up I slip the clutch a lil to load everything up then drop it at launch. Dont just sit staged slipping the clutch.

 

i have a 1988 N/A convertible only upgrades are exhaust and air filter it was boging but i tried droping the clutch at 5ksh and it dint bog if i drop the clutch at above 6k it stays there burning out for a second or so. and and as for sliping i gatta practice my sliping because last time i did it i smelled burnt clutch all the way home.

 

How do you slip a clutch at the line without moving?

10

 

With the line lock.

Don't think of it as slipping the clutch but more as loading the driveline. It takes the slack out of the driveline and reduces a lot of shock.

 

So, you take the slack out, and then drop it when the light turns green?

 

I personally don't but that is how many do it. You will also cut more consistent lights because your foot moves less before the car starts to move.

 

If you are on street tires - slip. If you feel ANY wheel hop, let off right away.

If you are on ET streets - drop the clutch. You should not get any wheel hop provided you have the right tire pressure.

Anthony

 

I have tried both methods but without success as yet,still trying to find that "sweetspot",last week my car ran a 10.6 at 144.7mph but with a 2.1 60ft .I have launched between 7000 and 9500 revs,it bogs upto 9000 but over that spins, seems a very fine line to launching it,going to be trying again at our annual rotary meeting in august with a good launch should get into the 9"s.

 

good info

 

Your case is different from the norm, you are making a ton of power and i'm not sure that the gear ratios are on the hks dogbox. Are you leaving on a 2step or just free revving?

Either way once you get a 1.5 60ft, you will have a mid 9sec car!

Anthony

 

http://www.gadgetvenue.com/wp-conten...bocop-suit.JPG

Drop it!

 

******' hilarious Rene! Imagine showing up to a Halloween party in that!

AND YES.....Drop it, then back peddle (feather) the throttle till you have traction. Just make sure you have a clutch that can handle dropping at decent revs. Depending on your port-say a streetport drop at 5000 or so....PPorts drop the clutch at 9000+, like this...
http://www.youtube.com/watch?v=UzehU-EDJfY
BTW...this is still one of the sickest vids out there!

 

Not entirely sure what the ratios are but the first gear is very long which isnt helping matters,i am going to try a 4.5 or 4.7 ratio diff,to try and compensate.I am free revving the engine,but 2 step is a possibility,what would the best way of doing this,i have a apexi pfc pro management system which has launch control on it,but has never been used, or do i use something else that cuts ignition, of which i run 2 crane cams fireball ignition amps.
Personally i think more and more seat time is the answer,the trouble with over here is we only have a couple of decent dragstrips and most of the time it is raining or windy,that last run with a 144.7 terminal was into a 50-60mph headwind,its meant to be summer but we havent seen any sun yet!Global warming no chance

 

I didnt have a line lock so a lil light pressure on the brake with the side of your foot should keep you there, or should I say it kept me there. I had a couple red lights but I got it down and my times improved a good bit because i was not spinning off the line.

 

Drop, slip, low rpm high rpm i tried them all saturday in a local 1/8 mile street event if your running the wrong tires your just going to have problems!
They wouldnt let me run the et streets so i ran on 275 street tires and is wasn't pretty.
Best 60 ft 1.96.
best trap 102.2.
best et 7.49.
But i did take the money so its ok!

The et streets were the best money ive spent for reduceing the et, 1.522 60 ft no wheel hop and the parts are still in one piece.

 

NICE!

 

Thanks

Any time the track writes you a check and you are able to drive home its a good day.

On the subject of the original post, there just isn't one answer to the slip/drop guestion there variables are just to great!
My advice practice small adjustments more practice and listen to what the cars telling you and give it to her!

 

I've had good luck with the drop. Netted a 1.52 off an 8k drop. You can see it here: http://www.youtube.com/watch?v=coxy4dOVI64

Some other good launches:
1.56 launch, you can hear it bang the 8100 limiter just before.
http://www.vimeo.com/1550870

Can't remember the 60', but its a good run:
http://www.youtube.com/watch?v=8KjeT7GOUds

The pic below describes it pretty well.