so I watched some videos of sled pulls last night, and I want to understand the launch technique... it seems like they bring the rpm's up slowly (get the turbo spooled?) and once they are at the rpm they want to launch at, they somehow let out the clutch... or otherwise start to transfer power to the ground slowly? how do they keep from burning up clutches... or in the case of an auto, how do they get the rpm's up without overcoming the stall?

 

I just hold down the brake in Low Range 4WD as hard as I can, spool er' up, and when I feel the brakes let loose a bit I release them and LAUNCH!

Done it 12+ times with no issues

 

ok, that makes sense. I guess I'm most curious about the manuals...

 

from what i uderstand you rev it up let the clutch up a bit to get the chain tight and build boost,once u get the boost going. then bam dump it!!! its very hard on clutches!!! i think everyone that sled pulls is runing a dual disc... a regular clutch just can handle the sliping.... im sure someone that knows beter then me will chime in soon...

justin

 

With a stick you just bring it up to the desired rpm you want to launch at and start slipping the clutch until it feels like it will take off, sometimes 5 feet sometimes 25 feet. It is very hard on even a good pulling clutch, figure a big charger or chargers and some tire and you're going to rebuild about every year

 

Or have a specific boost fooler for yr box and then the boost comes

 

yeah i just ordered a sbc dd clutch. peter said that if i dont hook up to a sled withen the first 10 miles, ill be alright. i still havent decided on what to do. i know i want to pull but i dunno if i want to risk breakin anything or losing. theres not to many diesels round here so i dont think ill come in dead last, but ya never know. so, to pull or not to pull? and if i do, 3rd on the low side? what kinda rpms? over 2000?

 

well since u got a massive clutch and a six speed

and a good fueling box... well 3rd low isnt outta the questions. As far as RPMS go, id say over 2500 possibly..

If i was gonna pull my 12V (provided that i had a good clutch) id probly rev her up to about 2200 being that my redline is less than yours, and slip the clutch till it grabbed, then just floor it when it hooks up and hold on, id probly use 3rd and low as well (supposing i had a really good clutch)

Tx

 

dpends on the sled sometimes too as for what rpm to come out if yr pulling with those running type sleds then u can come out easy say 2000 then start laying into it cause thos sleds dont hit u till the end say 270 depends on the sled man .. As for those old ones were its hard to take off then i like to keep my rpms high 3000 + for me

 

If you have a DD run it up to 3 grand start letting the clutch out to build boost. Once you start letting he clutch out count out loud, in your head, what ever one thousand one, one thousand two, one thousand three. By the time you get to three you should be out of the clutch. If your not your going to smoke it in short order. What gear you run in depends on your HP TQ and tire size. I've heard of guys pulling in 5th low, but they had the power to do it. I'm currently only in the mid 300's so I pull in 3rd low. Once I'm closer to mid 4's or 5 I'll probably pull in 4th low. It also depends on the track conditions. If you dont like the gear you have you usually have 75 feet.

 

this is the advice van haisley gave me. get your rpm up to 2500 start to let off of the clutch and slip it for about 5ft or one full tire rotation then dump it. practice in gravel or dirt so you don't make a fool of yourself on your first pull

 

If ya got a good clutch then the proper rpm is when you can't push the pedal down anymore

 

Thats right!!
I got to about 4500 rpms when I let out of the clutch. my tach only goes to 4k so thats a guess but the needle is pointing straight down
DM01