Mixed ratio rocker arms?

[Silly Seville]

Hey Guys...who has opinions on mixed ratio rocker arms in a Vortec 350 build? Specifically, I want to run a 350 Ramjet/383HT cam #14097395 with 1.5's on the exhaust for standard .451 lift, and 1.6's on the intake for a .459 lift. My reason for keeping stock exhaust lift is a 1.6 would take me to .481, and I've heard that the Vortec heads don't appreciate anything much past .480 Has anyone actually done this combo with any success or failure and lived to tell about it? FWIW, I'm planning on keeping my stock springs, pushrods and keepers, unless someone can convince me of a need to change them out with new. Thanks!

 

[Bondo]

Re: Mixed ratio rocker arms?

Hey Guys...who has opinions on mixed ratio rocker arms in a Vortec 350 build? Specifically, I want to run a 350 Ramjet/383HT cam #14097395 with 1.5's on the exhaust for standard .451 lift, and 1.6's on the intake for a .459 lift. My reason for keeping stock exhaust lift is a 1.6 would take me to .481, and I've heard that the Vortec heads don't appreciate anything much past .480 Has anyone actually done this combo with any success or failure and lived to tell about it? FWIW, I'm planning on keeping my stock springs, pushrods and keepers, unless someone can convince me of a need to change them out with new. Thanks!

Ayuh,... The SBC in marine applications suffers from a poor Exhaust flow, not intake flow...
Unless yer willin' to spend a fortune on true headers, yer wasting yer time...
The motor can't use more intake flow, if it can't get rid of it's exhaust..

 

[Silly Seville]

Re: Mixed ratio rocker arms?

Thanks Bondo. That sounds like very good information and advice.

 

[John_S]

Re: Mixed ratio rocker arms?

It is interesting that the ramjet crate engine comes with the Merc marine cam. It is also interesting that it uses iron vortec heads, and 1.6 rockers.