Nasty Girl hits 10.65
- Thread starter mde
- Start date
so if no burn outs what do we do with all this power 1/4 drag racing must be even harder on the trans if i knew burn outs were so bad i would have never build this truck
The burn outs are made to heat up the slicks, otherwise he didn't had traction on the track by shifting in next gear
We go 1.5x in a RWD Corvette on DOT drag tires without heating at all. Don't heat Casper up either. Pretty rare for any truck to holeshot Casper at the track.
If heat a big concern use tire heaters instead of burnouts. But modern DOT racing compounds work well down to 30 deg.
what we started doing was holding the truck in 2nd gear to do the burnout.takes a bit longer to heat the tires up but doesnt get the rear tires rolling super fast so not such a shock can occur if a shift happens at the same time the rear tires catch traction at the end of the burnout...
So when a stupid little kid in a honda pulls up next to me at a light and i put put my foot to the floor and spin through first and half way through second while i am still accelerating your telling me thats bad news???
Just wanted to make sure...so the bad part is the shock on the tranny when the tires catch dry pavement?
exactly!
no joke, Ive probably only done ONE (maybe two) "solid" burnouts in my truck and the trans has hardly given me any trouble since I built it. That was over 75,000 miles ago and the trans has not been out of the truck to date. The shockload that occurs doing a "standing" burnout with a clutch to clutch trans is killer. Especially with the way the allison's ratios are setup/spaced.
Then if you're REALLY stupid, you'll do a huge ass standing burnout, let'er rip right up to 5th gear locked up, and then side step the gas pedal. Watch what happends then. :cool2:
Is converter lockup on nasty fast and consistant? Or does it sometimes hang and waste some time before the TCM finally locks the converter? It sounds like nasty bounced off the rev limiter (I would imagine the hard limiter set in the FICM, im sure tony has the ECM's internal rev limit turned off) a few times at the top of second (??) gear
ben
hmmm i have done several 5th gear rolling burnout forma 10psi launch... never had a shifting issue ...........
only issue i had has shortly after haveing it built and a filter change fixed that.
but i can understand how that there could be damage done from it.
only issue i had has shortly after haveing it built and a filter change fixed that.
but i can understand how that there could be damage done from it.
i honestky think the more power being applied during the burnout has a good deal to do with potential damage that may accur.my first level 5 i did funny car burn outs all the time andnever had a problem till the output shaft broke.buck had lots of problems with burnouts so we went to using 2nd gear...
If i understand Mike correctly burn outs are good for no truck. What he is trying to say is when u do your 1st 2nd 3rd or 4th or hell even 5th gear burn out and u let off sudden that is bad on all the hard parts in any tranny. Clucths are still smoken hot. Just like having a cool down timer u want it to cool down before u shut it off.
Actually, I think the problem is when you are doing a burnout with a lot of momentum/tire speed built up, and you all of a sudden grab traction and all that tire speed tries to accelerate the truck. That's a lot of force on the clutches, namely the C1s. I know I toasted a trans on a bad spinning launch that caught traction all of a sudden.
that sound alot like wheel hop/axle warp conditon. unload then shocking the system thus breaking stuff.
No, it was wheel spin. The track prep was shit and I didn't get a good launch, but it caught traction after the 1-2 shift.
street tires are a lot different than slicks. they actually loss grip when they get hot.
try this, jack up your truck, leave it in 2wd, run it up to 80mph or more and have someone drop the jack
the tranny or drive shaft or axle is about to become many small pieces
w/ modern slicks all you need is a haze from them to make them ready to go.
I used to do the funny car burnouts, they're a blast, 140-160 mph tire speed and get stopped at half track and back up.
track prep is most important.
when I worked the starting line at IRP it was 99* and sunny, I used a lot of VHT and my shoes would stick to the track like glue. didn't see a lot of tire spin unless it was guys running mud tires in 2wd.
hope you get it figured out Keith. what do you have done to the rear end as far as bars. what shocks are you running?
set up a video camera on the tires, put a white line on them, so you can see what they're doing when you launch. you should see a lot of wrinkle and a little slip. also see how much the front end is unloading on launch too.