I was dealing with high slip numbers until I pulled my drive off and someone scribed in the new 1.65 ratio. It's a long shot but a viable question to ask.

The above must be a typo. What do you really have ?

That's what it says in the build sheet my friend.

Drive ratio is 1.5

It's still a typo.

Find out what you have.

If it's a 215cc pro topline head and there wasn't something seriously wrong elsewhere, turning the same outdrive ratio as with the previous engine, I'd think once it spun past 3500rpm it would come alive and really rip----- excuse me for missing that line on the heads earlier, as the 420hp is very easy to believe if you have something aftermarket along those lines.....

not a typo. Called and verified. why do you believe its a typo

thats what we thought... hence my conundrum.....

How does it sound when it's to the wall? No hesitation, misfire, bucking, surging, just out of nuts?

Need to verify ignition timing and fuel pressure.... I know some head designs would actually make more power with less timing than some of the standard stuff and have power fall off if too advanced.

210+cc heads do not have small 1.94/1.50 valves,no matter who makes them.

So, I just want to know exactly what you have so I can know what power the engine should make when properly tuned and rigged as part of my helping to diagnose what your issue may be.

Mechanic said, they are 1.94/1.5. Said they produce better flow than 2.02s under 5000 rpm. Again the way it is set up I can't push it past 4800 and his reasoning is saving the drive.. sorry for any confusion but I don't know enough myself to answer the technical questions.. just doing a lot of reading to educate myself. your help is appreciated