Is it possible to get big power using the 425? If I ran a VN headed 355 stroker that makes 260rwkw using the same dual plane low rise manifold, but with a carby rather than the mixer, what could I expect from the gas? Would I have to change the cam to something lumpier to get similar characteristics, as in if a 234 deg at .050" cam suits a certain stall speed on petrol, can I run more duration with the same stall on gas? Would running a double pumper baseplate instead of the current QJ baseplate help much? I'm currently running a 3.45 rear end and a 2200rpm stall converter. With a 425 on top of a 355 stroker, what's the most duration I should run without changing either of those? What power could I expect from that? If I could get decent power without going for huge gears and a massive stall, I'd prefer to.

I used a 425 with 300rwkw in mind on a gas vlt.. however your v8 will ingest more air to make less power... so it'd be close, id go two just to be safe.

You'd need to adapt a second one to the manifold.

I'm getting my ute put on gas soonish(jan I hope) and the guy from the hoppers gas joint said I'd need 2 for a 355.

Hay guy l`ll tell you the bottom line about the impco 425 it`s a 425cfm gas mixer and it`s rated at 286hp it`s not a Sh*T mixer, it is small, and they need vacuum to work, like a SU l have seen them slowy start to shut on the dyno`s at WOT with motors with big cams, would anyone put a 465 holley on a 500hp motor!!!!!!

lol well said!

Quote: Originally Posted by lmtuff Hay guy l`ll tell you the bottom line about the impco 425 it`s a 425cfm gas mixer and it`s rated at 286hp it`s not a Sh*T mixer, it is small, and they need vacuum to work, like a SU l have seen them slowy start to shut on the dyno`s at WOT with motors with big cams, would anyone put a 465 holley on a 500hp motor!!!!!! LOL the bottom line is.. u dont know what ur talking about.