In theory (as always) what kind of power can I expect by changing from my stock TBI intake and tb to this manifold?

 

Ok, now that ive had my fun with the 2x4 for the BBC how about this manifold?

 

anotherview

 

its going to be way to much plenum for your L03.

you want something like a edelbrock performer RPM or the sort,

A high rise dual plane.

That single plane will sacrifice low rpm power for high rpm power.

your L03 ONLY makes low rpm power, so get an intake to match.

your car might seem slower with the intake you posted.

 

I was gonna set it up with a 650 or 700cfm carb.

And elaborate on the plenum thing

 

well lets see, with a similar set up my 396 BBC in my 65 elky idles just about 2100 rpms. I dont think your engine could suck enough air through that to keep it running.

 

I was thinking about getting an aftermarket 4" cowl hood if that makes a difference

 

to be honest that weiand intake yest looks sweet and all i know a guy in town who has it with two 600ish cfm holleys atop and his truck is pretty fast altho it is a 350 i personally dont like taht look i would get a edelbrock performer rpm or victor jr. with a 600-700 cfm carb i would recomend edelbrock/carter due to they are less maintnence then holley demons are good but expensive.

 

plenum is the air space that the intake runners feed from. All in all it is just too big of an intake for a near stock 305. It shouldn't even be a consideration.

Those runners aren't going to be able to provide the air velocity at lower rpm. the usuable powerband for that intake is probably 3500-7500rpm.

and everything else about your engine is about 1200-4500.

not a good match.

 

Damn...I think I got a few other SBC manifolds somewhere. I gotta look.
But it would look hellua good tho