Michael Mansour

I suspect that my front pulley is not from the engine I have, it has been rebuilt before not by myself. I have driven the car for a while with no big issues like loud pinging or misfiring, but its not as smooth as it should be, i tried setting the timing using the flywheel notch method, i have an s5 turbo flywheel which has a section of the flywheel filled in not cut out, I tried putting that to the 9 oclock position(exhaust and intake port side) and restabbing the cas and I got bad results(ping/cant rev). I have an s4 rx7 with an s5 engine and turbo, I have no emission,P/S,A/C,air pump, omp delete with premix. What is another way i can find rotor 1 tdc? I have seen some methods with a wire.

insightful

best method is to buy a hub that has been timed. you can buy OEM paired units new still, you can buy aftermarket billet units or you can PM me if you want to send yours to be reconditioned and restamped to an even more accurate marking than the factory used.

unfortunately all other methods for finding an accurate TDC are myths and not nearly as accurate as those posters lead you to believe. the spark plug hole method is the worst, using the flywheel or eyeballing the e-shaft key is also still very rough. aside from that you got nothing to work with aside from a properly timed pulley. i'm sure you hoped there was an easy answer, unfortunately there isn't one, because these aren't boingers with vertical planes to measure. the plug hole method seemed the most feasable, until i actually tested it and found the results were quite a ways off because the spark plug holes in all series of rotary engine are not placed in the engine in such a manner that you can use for such a purpose.

Rotary Alkymist

You should be able to feel it by hand. If you turn the engine until apex seal is in the middle of the L2 spark plug hole you will be very close to TDC. Make a mark on the pulley. You should feel maximum resistance at TDC. It's hard to explain but TDC will be the hardest point to turn the engine to and is easily passed with uncontrolled force. When you home in on it tighten up your arms when you pull so you'll have more control. You should be close enough that you could run it and set it with the CAS.

Nothing beats having the right pulley though. That sucks.

insightful

no one should be using "hand feel" to time a turbo engine, that's how apex seals liberate themselves.

Rotary Alkymist

No one should but you could. So you're claiming that you could recondition and restamp my pulley to be even more accurate than stock? Haha. How much do you charge for that?

insightful

the stock pulley holes have slop, which allows timing to be off by as much as 7 degrees even on a new set of pulleys.

i'm not sure why mazda felt the need to make 2 sets of pulleys for the FC or to even not mark the pre 1986 pulleys on the old 12A and 13B engines which could be spun 3/4 revolutions and still bolt on. there has been plenty of timing stigma with these engines, many people not even aware how far off time their engines were. they finally got things right with the REW and MSP engines which have doweled pins and almost no play in the timing marks.