First I am running new style BFG DR 315 18's. My best with stock clutch was 1.653. My last time out with stock clutch I ran: 1.75, 1.76, 1.77, 1.79, 1.70, 1.71, 1.76.

Installed new Textralia clutch, and installer didn't change f-body bleeder on slave to Z06 bleeder (shorter) and had pedal stick on sec launch and complete failure on 3rd launch from bleeder snapping off. When repairing I noticed heat bluing from slipping inbetween complete failure.

With that said, after shop replaced slave, here are 60's so far: 2.05, 1.93, 1.92,1.89, 1.86, 1.75, 1.83, 1.94, 1.80, 1.83, 1.96, 1.97, 1.94, 2.07, 1.77, 1.93, 1.91, 1.84, 1.76, 1.84, 1.92, 1.94, 2.00, 1.96, 1.86, 1.93, 1.91, 1.87 in order 1st to last.

I get pretty bad spin and wheel hop 90% of the time (nun before new clutch). I have 78 runs on these tires. I have tried different pressures, different launch rpms, 3000/3200/3500/3600/3800/4000, n2o, no n2o. Seems now I have to burn the crap out of them to get anything on launch, and my traps are down. I also notice more chirpping when changing gears, even when hitting 4th. Are these tires just worn out? They still look good and are no where near bald.

Any advice or insight would certainly be welcomed, as this is driving me nuts.
Thanks in advance.
Robert

 

Robert...your bfg's are toast. ive seen the same problem with the tires, even though they look okay to the eye. Get some et streets and solve the hopping problems along with better et's and a happier drivetrain.
Regards Wash

 

ET Streets, ET Streets, ET Streets....
Ron

 

I never got any wheelhop with bfg's and seemed to work until the cords starting showing. Not sure but new tires can't hurt, maybe etstreets or mt drag radials or hoosier drag radials.

 

Rob, you told me when I bought your used DR's w/ the cords showing that it means they're real sticky!!!
Ron

 

Hey Robert.

I suspect the change you have experienced is due to the additional clamping power of the Aussie clutch.

With your stock clutch, there was some slippage during engagement even on a very fast release. Ditto on strong shifts.

Now with the Aussie clutch, you've got a heap more clamping power that increases the shock if you still use a fast release.

I'd suggest shooting a PM to J-Rod. He has made the jump to that clutch and can offer informed perspective.

Are the slower 60' times you are citing still all-motor, no spray?

With 363 rwhp and stock clutch, my 60' times remained pretty consistent in BFGs right down to the cords. In fact they were a little more consistent once those pesky treads were worn away. But once that occurred, it was really important to ensure that no water from the burnout box is slung up into the wheel-well and then can drip back down onto the heated slick-BFGs. Spin-city.

Ranger

 

Ranger, at first I agreed with everyone that tires may be shot. However, after checking, I found wear bars are not even being touched yet. I now have 87 passes on these tires.

All passes sited have been n/a, as was checking n2o last night and have wiring problem and it is not working at all, even when I thought I was using. This is also backed up by my mph, as with spray I get mid 120's usually, and haven't broke 114mph in sited 60's.

I think now I agree with what you say about clamping force. I was in such a habit of quick releasing at about 3500, just doesn't work for new set-up. Last night towards end, I started doing heaver burn-outs and launching at 4500rpm, results: 1.73, 1.74 and 1.75 (earler was all 1.8x's) and gained back 2-tenths in ET. Even at that rpm some slight bogging was happening, so I believe I still need to up rpm at launch.

Conclusion, just needed to adjust my launch/burn-out for new clutch, and tires are still fine even with many passes. There is definately some more time to be knocked off 60'er with a little more seat time. It's amazing how one change can through your whole launch off to point of a relearn/adjustment factor. I may have to slow my shifting down a tad also, as a slight spin is being had all the way into 4th, at least until I change over to ET streets. I'm sure this may be taking a bit off my ET as well, the best last night was 12.1x.

Thanks Ranger, once again you've hit the nail on the head, first time.
Robert