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How likely is det happening b/c of timing scatter? Can this be one of the reasons we blow are motors frequently? If so, why aren't more of us switching over? It seems like a genuine issue.

Quote:

Originally Posted by Joe Perez (Post 4675402)

Even having not yet seen the new wheel in person, I can vouch for this. There is an enormous amount of spark scatter at high RPM on the '90-'97 cars, owing to flex of the timing belt. I observed approximately 10° of scatter on my '92 engine using the original CAS, and this was reduced to maybe 1° after I converted to a 36-1 wheel. It should be noted that since this was with an MS1, there was functionally no difference between my 36 tooth wheel and a lower toothcount wheel (the MS1 only pays attention to two teeth on the wheel, regardless of how many there actually are), so this will pay huge dividends for anybody interested in really tightly tuning their ignition map.

I can tell you one thing.

I had swapped my block and forgot to tension my timing belt. Was able to set timing in MS and drive many miles, even dyno.

I eventually fitted MS3 a few months later. Had weird misfire issues and it just didnt run correctly. turns out, the processor is so much faster in ms3, it was able to pick up the problem and things were spark/fueling at odd times in relation to the crank cause the belt had so much slooooop.

once I tighten the TB, I had to resync the trigger angle, and then I was detonating in higher rpms on the current spark map.

I think on a motor that is pushing the boundaries, you need all the accuracy you can get. I have switched to a crank trigger myself. I can not imagine relying on the cam pulley for my high strung motor