Re: the rods: I’ve heard (dangerous to put faith into rumors, I know) that these rods are weak and that I ‘should’ have used M rods.

The early B20 rods have more tensile strength than anything found in a B21 or B23. They'll hold 300HP and hang together at 7000rpm with ease. The B21 rods might be able to handle some more HP, but they are a liability above 6000rpm. The two failings of the latter rod is that they cheaped out on the material + the cheaped out on the rod bolts. The B21 rods look like the forging was designed to use good capscrews like B230 rods, but cheaped out at the last minute.

The head was ported. Unfortunately (and as with many port jobs on these heads) it didn’t improve flow over stock on the intake side.

A 10% gain up to .25D lift is normal, without widening the SSR, the flow then goes away at higher lift, but that is no concern with any cam that lasts for long on the street.

What are the flow figures? Most of my records are at 1/4,2/4,3/4,1&5/4 & .25D. Maybe your head was a really good one to begin with.





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Three 164's, Two 144's, One 142 & a partridge in a pear tree.