Did the MR get a different cam than it's GSR brother? I was searching around trying to identify a set of OEM camshafts and came across http://www.lancerregister.com/showth...entify+mr+cams

The cams in question have a number stamped along the edge of the cam like the bottom ones in the picture, but have a toolmark like the "MR" cams in the picture (looks like a little house, or maybe a P) definitely not a 2 rollmark. What's the deal?

 

The link in your thread is from the British Evo forum, "LancerRegister". To make a long story short, the British Market VIII MR's, unlike USDM MR'S, were fitted from the factory with cams slightly more radical than the British Market GSR's. I think this holds true likewise, for JDM VIII MR cams as well.

USDM VIII MR's are not fitted with those "special" cams. Instead all USDM EVO engines were fitted with the milder factory cam grind. This is probably due to no Federal and CARB testing or approval for engines fitted with the bumped MR grind.

 

Same cams in the us across the bar

 

Uk 8 mr were imported jdm 8mr

 

Gotcha, now for the next question. I see even here on EVOM there is a discrepancy in the stock cam specs.
https://www.evolutionm.net/forums/ev...d-updated.html claims 248 duration on both intake and exhaust with 9.8mm lift on the intake and 9.32 on the exhaust
https://www.evolutionm.net/forums/ev...no-replys.html claims 260 on the intake and 256 on the exhaust with 10mm lift on the intake and 9.5mm on the exhaust.

Who's correct?

 

The first thread you posted is correct

 

Interesting you should say that, do you have a source that confirms the first thread's specs? Further research in the book "How to Build Max Performance Mitsubishi 4G63t Engines" states the stock Evo cams are 260 intake/256 exhaust with no mention of lift, which would seem to support the second thread's numbers as being correct. I'd like to know where these conflicting numbers are originating.