Need help with finding right jetting...

[383man]

They always say when towing a car with the rear wheels on the ground to unhook the driveshaft even if you have it in neutral or you can hurt the trans and I have seen it done. When I worked at an independent shop years ago one of the tow truck drivers towed a car about 20 miles and he had the rear wheels on the ground and he did not unhook the driveshaft and it burnt the trans up but good.

As for jetting I am still old school and do it by reading the plugs as I do not have an 02 setup on my car. As said I jet for mph until it falls off. Ron

 

[dvw]

I can tell you guys that I build and maintain my own transmissions. You are right there will be no pressurized lube. Contrary to a statement in an earlier post the output shaft does not drive the pump. The tail shaft bushing is splash lubed anyway. By the time everything stops spinning your at the return road anyway. There is no way the bushings run out of lube in a 1000 or so feet. We've been doing this for a few years with 2 cars to check jetting. Plugs read just like is was in neutral. The engine rpm slowly ramps down over a few seconds. Both run 140+. Neither has shown any internal wear. It's a hell of a lot safer than putting it into neutral.
Doug

 

[383man]

Funny as now I remember that they used to say if you tow a car with the rear wheels on the ground the only kind that is safe without taking the driveshaft out is the auto trans with a rear pump. I do agree with "dvw" about shutting it off in gear at the track. Ron

 

[dvw]

Ron does his own transmissions as well.
Doug

 

[SUPERSTOCKRACER]

I can tell you guys that I build and maintain my own transmissions. You are right there will be no pressurized lube. Contrary to a statement in an earlier post the output shaft does not drive the pump. The tail shaft bushing is splash lubed anyway. By the time everything stops spinning your at the return road anyway. There is no way the bushings run out of lube in a 1000 or so feet. We've been doing this for a few years with 2 cars to check jetting. Plugs read just like is was in neutral. The engine rpm slowly ramps down over a few seconds. Both run 140+. Neither has shown any internal wear. It's a hell of a lot safer than putting it into neutral.
Doug

Ask Charlie Wescott Jr.on this matter. Not only decelerating in gear are super hard on engine parts. Wescott says decelerating in gear is like going down the 1/4 mile in reverse.
They make free neutral valvebodies for reason.

 

[dvw]

Not doubting that decell has more effect than neutral . In my 40+ years of racing ive had one motor failure. On the other hand I would bet Tha 99% of the cars that are drag raced slow down in gear. But back to the original topic. The car can be shut off or put in neutral to read plugs.
Doug