There are a couple of other things to consider about roller rockers.
The bigger benefit beyond performance is that they impart much less
stress to the valvetrain overall, making your head and valve guides last
longer. They are also stiffer, resulting in less deflection when a
valve is opened and follow the pushrods better, resulting in smoother
running.
Are they a miracle power source? No. Are they a way to protect a big
investment in a new head? Yes.
I strongly recdommend you go to Doug Jackson's website and look at his
methodical and scientific tests on roller rockers before making a
decision. The address is:
http://www.mgbmga.com/tech/mgb16.htm
He also sells roller rockers and they're a lot cheaper than the Moss
variety. I'd bet they're higher quality too, knowing Doug. You may
also want to get Doug on the phone regarding your aluminum head. He did
a number of flow analyses and lots of testing on these. I don't think
he liked them very much.
YMMV
Andy
Barney Gaylord wrote:
>
> At 07:18 PM 11/22/98 EST, BDurgin1@aol.com wrote:
> >I've decided to buy an alumininum head (not cross-flow) with the new valves
> >etc for my 64 B with a 3 main engine. .... I've been looking at the roller
> assemblies .... was wondering if they are indeed worth the BIG $$$? I'm
> trying to squeeze more HP out of the engine .... by "bolting" on stuff
> like K&N's, modified head, etc.
>
> I wouldn't spend $$$$ just because they're roller rockers, but, most roller
> rockers also have a different ratio of arm length and increase the valve
> lift significantly for better flow without changing the valve timing. This
> is one way to get more torque out of it without screwing up the other
> running characteristics like it may do with a more radical cam.
>
> $.02,
>
> Barney Gaylord
> 1958 MGA with an attitude
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