What NOT to do to your turbo!!!

[rapidray]

This will slow a 7.80 second bike down to an 8.80 really quick! The boost gauge tell tale was at 32 PSI at the end of the run! Ray.

[rapidray]

Another shot! Ray.

[rapidray]

Last one for now. Ray.

[Steve]

Bummer, Ray, was that one of yours?

I am surprised that something like that did NOT happen to my little car, about 30 years ago.
Had a '74 Corolla, 1600 engine, 5 speed tranny. Had a Rayjay turbo (don't remember which model) installed, then modified a bit.
Had to borrow a manifold pressure gauge from my Peterbilt to find that I was running 22 psi of boost.
Estimated 300+ hp at the rear wheels. Never got a dyno reading with 22 psi, but it had 192 hp at the wheels with 11 psi.
Not too many 4-cylinder Toyotas of that era would hit redline in 5th gear. 125 mph showing on the speedo. 1978 Corvette still in the rearview mirror.

.

[rapidray]

The bike is owned by a friend of mine & is a Top Gas bike. It's a 1400cc GS 1150 car tire chromoly chassis bike. It has gone 7.80s at 175 before & goes straight as an arrow! It has a 3 stage boost controller on it & he was on his 5th re-licensing pass when this happened Saturday morning. If it had happened only ONE run later, he would've finished licensing! We decided to turn the boost down a little when we go back out in 2 weeks to make the last license run. The amazing thing is that I pulled the valve cover & no damage. Then we pulled the head & found a dime sized piece of aluminum on top of the #3 piston. NO damage to the motor! Talk about LUCKY!!! We figure it had to have happened when he pulled in the clutch & shut the throttle at the end of the run. I'm tearing the whole bottom end down now to make SURE no metal went into the motor. I will hone, ring, spring, & seal the motor & make it all fresh for the next time out. Ray.

[SqDancerLynn1]

Big Ouch on that one, but Racing is expensive

[steve murdoch]

Top Gas is 8.20 if i remember correct?
Ray, is it easier to tune the bike/boost back a bit to fit the class or would it be better to let the rider control the times.

[rapidray]

I like to set it up with the boost so it can just be run out the back door every time. I'll set it up with just enough boost to go 8.17 or 8.18 & then have the rider run it hard every time. It's actually easier on the motor than trying to go on & off the throttle. Plus, a turbo looses too much boost when you try to "pedal" it. Ray.