Some questions (pictures soon).

[Blessed66]

Hi everyone.

I've been recently toying with a project (since my 66 is on hold) on my 1984 GMC LWB. This truck is a 5.0 (LE9) with a TH350 (MX1) and approximately 130,xxx miles. It has sat up some and then I sort of inherit it. That's a story for a different day, however.

I will try to add some pictures later, but this is where I'm at (so far). I have checked some of the basics, changed engine oil (some leaks - valve cover gaskets for sure, probably oil pan and/or rear main as well), checked trans fluid (still full and darker red, but not burned surprisingly), and have been removing A/C and emissions equipment (A/C completely empty, not even a hiss, R4 compressor locked, metal shavings everywhere... no emissions hoses stood the test of time, or being parked in rural Texas).

Right now, this truck barely runs - partly due to vacuum leaks I caused () and not having a tune-up done in the last 15 years, probably. But, it still starts and runs decently given all of the "damage" I've done.

I plan on replacing the intake manifold and carb, regardless, to simplify my vacuum situation and help breathe some life back into this truck. Nothing crazy - I'm thinking this 305 probably doesn't need much more than a 500 cfm carb to begin with. Memory serves me right, they don't breathe like their 4" bore brothers.

This is the basic part of my questions, for now...

Given the potential for other issues to pop up (haven't popped diff cover, checked suspension pieces, or even figured out exactly what I want besides a long & low cruising truck), I am going to invest in a set of cheaper headers, intake and carb just to get this truck running somewhat reliably right now.

Is my cfm assumption (~500 cfm) an accurate starting point?
Is there anything specific to the 305/TH350 I should be concerned with?
While I'm sure getting a 4" bore engine would be better for performance options, is there a feasible alternative to building what I have into being decent in terms of power?

More questions (and pictures) to come, I'm sure.