305 GMC preject.
There was a time when "hotrodders", had to virtually make a lot of their own parts; I think it was called "the old days". Some of them used odd engines as a starting point. The question about the old GMC has come up many times on this site. The way I see it, you're doing this for a grade in school, and also to be different. More "power" to you, and not in the just the vernacular either. You're not going to build any kind of screamer, and you already know that. First off, you're working on the intake and exhaust systems, freeing up things there can only help, everyone does that. An engine is an air pump, and the more air you can move, the better. Later, you can delve into the engine and heads, on the camshaft ( someone can regrind it ), do some portwork and angle milling ( be careful here with your use of steel to make your intake,as milling the heads also means milling the intake ). I'll bet this truck's exhaust will have a truley unique sound. Now, if it were me, I would conscider the turbocharging route, and even use the stock intake and exhaust manifolds. But, that's just me; good luck with your project, and see if you can find a pair of those "kilt like" painted valve covers. I looked at your intake manifold in progress, keep it up.
It looks to me like the stock intake manifold is of the open plenum design, it looks surprisingly a lot like the Pontiac 301 carbed intake, and looks to have siamesed ports also, like the Pontiac 301, save for yours being for a single throat carb. Maybe start with making an open plenum manifold, it would probably be the easiest.
Last edited by junior stocker; 03-12-2009 at 12:30 AM.