The 500 and 731/800 kent cams
Turbo Mini Forums

As promised 1 year ago here (attached) is the profile of the 731 camshaft I bought in the US. I show it along with the MD266 and MD256 (both brand new) profiles. I use theoretical rocker ratio 1.25:1 (Kent use 1.28) and the valve clearance of 0.4mm must be deduced to get the advertised lifts.

I'm not sure it's really a 731. It should be, it's a star pump drive and there are 3 rings on the camshaft. But the lift at TDC is much higher than advertised by Kent. Intake and exhaust cams are identical like on 731.
The MD256 looks strange compared to MD266 but I'm pretty sure about the measures I did. I don't have this MD256 any longer.
I was not able to find the advertised timings especially because the take-off/landing areas are very carefully designed and are very smooth, so it's difficult to located the exact 0.4mm lift point that Kent use as reference.

Assuming it's a 731 the main difference is on the intake cam which is shorter on MD266. Exhaust cams are quite similar, the 266 one is a bit shorter. 731 overlap is much bigger (despite the Kent numbers)

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Edited by alpa on 25th Feb, 2010.

std 998 A+, g295, MD266, RHF4, 109hp @0.8bar/5400rpm