400hp on 350ci

I'm looking to build a v8 rx7 and im a beginner
I'm looking for 400hp at the crank I don't need/want much higher.
I'm planning on rebuilding the 350 but thing is like I said I'm new to this and currently I just have a stripped down 350 block, did run before but it was filthy and the intake was clogged.
So I need a new top end. I'm on a budget build
I read here that cast iron heads are better than aluminum heads(and far cheaper), so I chose the cast iron vortec heads as well as this: http://www.jegs.com/i/GM+Performanc...8060K/10002/-1#
any suggestions?


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Vortech heads, and the right cam will get you to 400HP pretty easily. There was a budget build in one of the rags a few months back that did a 430 or so HP vortech build.

THink the whole thing was under $3000. I'll see if I can find it and post a link.

If those are the Mexican casting I would CC the intake runners as we have seen them 159CC not 170CC like they are suppose to be which will kill your HP.

With the old 906 casting and and 10:5 compression and a hyd. cam we saw 432 on the engine dyno and 460ish on the torque.

Block was blue printed zero decked, plate honed ETC.

Heads were bowl howged and good valve job.

Okay like I said I'm a rookie
My 350 is out of a chevy g20 1983
can you explain to me what you just said?
what do you mean "Mexican casting" and "CC the intake runners" and a "hyd. cam"?
whats all that mean?

edit: would someone please give me some suggestions on what to look for in a good rebuild and why those suggestions make it good?

Heads cast in Mexico, Intake runners were smaller than they should've been. Intake runners should have held 170cc's of liquid but only held 159cc.
hyd. cam = Hydraulic Lifter Camshaft

thankyou guys
this site is awesome!

THe origional production L-31 vortec heads (062-906 castings) were cast in St. Catharines Ont. These were the good ones. (170cc port, 230ish cfm flow)
(I am unaware if these heads were also cast else where in the US.)

Then GM in their wisdom switched this state of the art plant over to V6, layed a lot of people off and moved the L-31 350 vortec head production to Mexico.
Apparantly the cast cores have not been maintained and the port dimentions arenow not the same as the old Made in Canada stuff.

So your options are buy the GMPP Bowtie vortecs, buy the RHS "906 torker vortecs"
Buy the EngineQuest Lightning vortecs, or port out the newer, crappier GM Mexican vortecs to get the flow back up.