Engine Builders talk.
Flat tops will be fine on 91. I blistered them on 87 and poor tuning. As long as the tune is safe it will be fine. I have coated Mahle hyperutectics now and they are fine. They have been going for around 140k. Being I tune I know how far I can push timing. If I was gonna do it all over again I would have gotten a more aggressive cam profile and used Motorcraft headgaskets. The Motorcraft
Are .008" thicker when compressed.
Are .008" thicker when compressed.
Would you have to deck your heads to be sure they run true or is it just good practice?
Thank you for taking the time to answer my questions.
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Joined: Sep 2011
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I have custom grind SHM cams that are very similar to the Comp 264s with a little more duration and a more aggressive lobe separation angle. They make a lot of torque down low and in the midrange but they are outilized of breath around 4800.
I honestly can't remember the last time I needed anything above 4800.
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Joined: May 2011
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It's a good deal but I don't truck buying used but built engines-unless it would be from someone extremely reputable
Alright guys I am trying to decide on a piston dish to go with Comp Cams XE262H or XE262AH. I would like to be able to run 89 octane if need be. I end up in some boonies sometimes that honestly just dont carry anything better at the pump.
Or better yet. What CR should I be shooting for?
Or better yet. What CR should I be shooting for?
Last edited by jprevat; Mar 24, 2016 at 12:40 PM.
I imagine that with a flat top I would be better off using the XE262H. I would also be right around 10.8 as far as my CR would go. Am I on the right track for 89 octane?