with a stock 12a in pretty good running condition and stock tranny, and what points should i shift at (1-2 @ 6500, 2-3 etc..or something like that) to get the most ....oomph (for lack of a better word) out of it?...

thanks alot,
Sam

 

when it beeps you shift


isaac

 

Assuming it still buzzes

Mine doesn't

 

Take it for a dyno run. Find out when the torque peaks. That's where you should aim to shift.

 

Another theory is you change after the peak so power spread is equal both sides of the peak. While power is decreasing after the peak it is still higher than the power at the new rpm if you shift at the peak. This is the reason for close ratio boxes.

 

On mine Ive found that 1-2 at about 6000rpm is about the best, it might just be me but it seems that revving slows down after 6 grand in gear (eg 5k to 6k is faster than 6k to 7k). However mine is mostly stock (Ive got a large cone air filter directly on the carburater), nikki 4bbl and just hit 150000 miles. it might have something to do with the torque band more than the horsepower band, but Im not certain of that. For me it seems the magic # is 6000. Also if you over rev, you have plenty of room left over
Best advise I have is just to experiment

 

Look around for dyno graphs of rotaries. If they're in good tune, they usually climb until the person in the car gets too chicken to push the engine more, or until the ignition system freaks out (for the FI guys with ignition control computers).

So the idea is to shift before it does damage to your engine, ie: when it buzzes at you, shift.

Of course, you'll only know about *your* car specifically by taking it on a dyno, but our graphs look a little different than our piston-engined counterparts.

Jon