95 Z28 M6 - CC306 w/ported factory heads

We're street tuning it so I can't confirm with actual numbers, but it felt like a monster at 12.9-13.0 vs mid 12's. Night and day difference when we leaned it out.

How much timing you running?

I'll have to get the tune in front of me, my friend has the tuning laptop at the moment. It's aggressive, but doesn't knock at all. What kind of timing do these cams like? I assume that as long as it's not knocking, I'm not going too far?

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Originally Posted by Mr. Brett

I'll have to get the tune in front of me, my friend has the tuning laptop at the moment. It's aggressive, but doesn't knock at all. What kind of timing do these cams like? I assume that as long as it's not knocking, I'm not going too far?

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sometime you can get more power out of it with less timing, and a leaner afr. i think i was running around 34-35 degrees on 93 octane.

i'd like to see your tune and datalog if you have them.

I'll get a copy and post it.

Car was running 34-37* at WOT, 12.7-13.0 AFR

I took the car out for a bit yesterday in the early morning when it was nice and cool, and the AFR was as low as 12.6 at times. I think I might need to do some more MAF tweaking and dial it in a bit. I'll make some changes this weekend and get a tune and updated scan posted. Thanks everyone for the feedback.

you tune to what the car wants, every set up being the same are different, looser tolerances in the motor, factory balancing, carbon build up ect. I have had two identical cars, basically the same mileage, same cams ect, put them on the dyno and one would like a richer A/F with more timing and the other Leaner with less timing, One made 20 more RWHP. Back in the day Chris Bennight was the LT1 Guru, he had a cam, bolt on only, M6 with a lot of gear and ran high 10's, Very aggressive tune, 39* total timing up top. Again, I tune to what the car wants, of course check your plugs for timing marks, heat ect..

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Originally Posted by Mr. Brett

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Note: I bought the car as it sits and have only tweaked the tune, so I don't know the exact flow specs on the heads. Stock bottom end, 119k. AFR is 12.9-13.2 at WOT. Thoughts? This seems awfully low compared to what I've seen from this setup. I have Edelbrock shorties, a high flow cat and an unknown catback (Magnaflow I think?). Peak torque came on at ~3k and stayed there, power climbed until redline. One theory is that I might be choking it with the shorties. Opti is newer, plugs are new, wires are good. Car runs great in general.

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Did you really only take it to factory redline of 5200rpm or was that an expression? That cam wants 6700. What springs are on it? Could be valve float, can you post the graph?

isnt factory like 5750 or something like that.