PDA

View Full Version : maybe dip into the twelves?



fasterthanyou
07-27-2011, 08:17 PM
at the track right now. Making some progress. Its hot out and im only making 13 psi but i just managed to crack off a 13.04 @ 104mph with a 2.04 60ft. Letting it cool down and going to lower the tire pressure in my slicks to 20psi and go for my first 12 sec pass!

XR7 Dave
07-27-2011, 09:09 PM
Hey that's pretty good. If you can get that 60 ft down where it belongs - 1.7 - then 12.50's aren't out of reach. Good luck!

fasterthanyou
07-27-2011, 10:25 PM
well, I'm home now.. Didn't get my 12 second pass :(

last pass of the night, lowered the tire pressure to 20psi. let the engine cool down to 140 degrees F, launched at 2krpm. spun pretty bad for about half a second, hooked up real good and then POP! something broke. this may sound stupid but I honestly have no idea what broke. I know the difference between wheel spin and just free revving. Its like as soon as the tires stopped spinning and grabbed, I heard a pop and the engine free revved to redline. I let off and revved it again with the same free-rev result. pulled to the side right away and got out. I figured it was an axle but the axles are intact, driveshaft is okay. I drove it around the pits and everything seems fine, I have all my gears and there are no vibrations.

:confused: drove it home and here I am. I didn't try to launch it again on my way home, just in case something really did brake. I'd rather be closer to home than 30 miles away. hm..

Mike8675309
07-27-2011, 10:45 PM
If you apply power does the car speed up or can did you have to be careful how much throttle you gave it? If the trac lock is tight, you could bust a axle but still move if you apply the power gently. It didn't pop out of gear did it?

fasterthanyou
07-27-2011, 11:08 PM
If you apply power does the car speed up or can did you have to be careful how much throttle you gave it? If the trac lock is tight, you could bust a axle but still move if you apply the power gently. It didn't pop out of gear did it?

really? a trac lock can do that? I had no idea. I'll have to look into it further tomorrow

Mike8675309
07-28-2011, 10:22 AM
A stock one will never do it. But if someone built it super tight, as some do, it might. It takes, if I recall, about 28lb/ft of torque to overcome the stock track lock if it's on spec. That's the preload via the s-spring in the housing. The car is too heavy and will easily overcome that torque bias if an axle is broken. But if you have it built tight, and the torque bias is higher, you might pull it off.

paintme205
08-03-2011, 01:50 PM
It might be worth taking the thirty minutes to pop both axles out and just look at them. It sounds really odd though:confused:

Congrats on the 13.04. WIth some practice, cooler weather, and good traction, that bird will be flying.