[67Lemons]

So with some years behind us now since this thread was started has anything changed? Is there a “new” grind that beats the preferred RA4/Rhoads combo for a 455? Doesn’t seem so but figured I’d bring this one to the top for another look.

[JLMounce]

Originally Posted by 67Lemons

So with some years behind us now since this thread was started has anything changed? Is there a “new” grind that beats the preferred RA4/Rhoads combo for a 455? Doesn’t seem so but figured I’d bring this one to the top for another look.

There's been a lot of development from 2017 until now. I'm not an expert and I won't pretend to be one, but I have some thoughts.

I don't think you'll ever be able to say that RAIV grind with, or without Rhoads lifters in a 455+ Pontiac is a bad combo. Jim Hand proved that combination could motivate a 4300 lb wagon to 11 second time slips with good traction. That's never not going to be the case (pardon the double negative).

That said, it's much easier to fit an overdrive transmission of almost any sort now. Torque converter technology has progressed. The prevalence of hydraulic roller cams has increased, as has induction side changes. These things combined make performance without sacrifice easier to obtain from the traditional Pontiac engine.

All you have to do is open your pocket book now and you can put a top end on these engines that has at least 300 cfm flow, with decent port velocity, on the intake. The addition of modern fuel and timing control lets you tame what once were fairly radical cams.

If that's not in your budget, or simply not your speed, you always have these tried and true combinations to fall back on with confidence. Make no mistake, a RAIV 455, is still a performance beast. But, to say we haven't progressed, would be disingenuous.