Thread: rebuilding a 350 that has 305 heads

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Vortec heads from a 350 will work fine. There are some aftermarket companies out there selling them. I even think Jeg's does too. I wish I could find a Ford stroker kit for as cheap as the 383 stroker kit you found. That is what I hate about trying to fix up my 302 is everything is way more than a Chevy.

I would like to get Vortec heads but then I would need to get a different intake wouldn't I? What about cam selection?

I thought the Edelbrock Performer Series intake manifold worked with Vortec heads? I mean, I am not saying it does but that is what I thought. Am I wrong?

GM Performance Parts and Edelbrock both make intake manifolds for Vortec heads. They start at about $150 from Summit.

There is an Edelbrock Performer that fits the Vortec Heads but I don't think mine is the one since it is attached to regular heads right now. I'll price out the Vortec heads with the new intake and cam to see if I can fit it into my budget.

Yeah if that is what you really want and I think would be worth it then you can always sell the intake you have now or keep and save it for another project for later. Those 305 heads are really constricting power. They are basically junk, especially with no work done on them.

Okay guys, here is what I am planning on doing. If the 350 does not need machine work than I am planning on buying the Sealed Power engine rebuild kit from Summit that makes 9.35:1 cr with 64cc heads. It goes for $219.95. I am also planning on buying the stock GM Vortec head kit with a performer intake from SPDC that costs $729.95. The only thing I have left to buy is the cam. What cam do you guys recommend? The stock vortec head kit says it is compatible with valve lift of up to 0.450". Should I go with the upgraded kit that is good for .550" lift?

Originally posted by richmondb
Okay guys, here is what I am planning on doing. If the 350 does not need machine work than I am planning on buying the Sealed Power engine rebuild kit from Summit that makes 9.35:1 cr with 64cc heads. It goes for $219.95. I am also planning on buying the stock GM Vortec head kit with a performer intake from SPDC that costs $729.95. The only thing I have left to buy is the cam. What cam do you guys recommend? The stock vortec head kit says it is compatible with valve lift of up to 0.450". Should I go with the upgraded kit that is good for .550" lift?

The G.M. Vortec heads are fine.But here is another idea.How about a Dart Iron Eagle SS head.1.94.1.50 stainless steel valves,165 cc intake ports,screw in studs,.Competion Products sells these for $ 560 plus shipping.If it where up to me I would buy these over the Vortec heads just based on the fact that they are a much heavier casting and less prone to cracking and wrapping.

Someone beat me to the small valves and chambers comment. You want some heads with the mighty 202s. Smoking at start up is a good indication that the valve guides in those heads are shot anyway. If you have a 2K budged, I'd spend half of it on heads. Get some good aluminum heads, and you're on the right track.

AS for the big block / small block vs. gas milage theory: The best way to get more power from an engine is to improve its EFFICIENCY. When you step up the compression, larger cam, headers, port n' polish, multi-angle valve grind, etc... you are improving the engine efficiency. Until you go to extremes.. and if you are doing a daily driver, then you don't want extremes. Extreme cams wear down, stiff springs stretch the timing chain, etc. If the price of gas is an issue, then build the 350 for 300-350 HP. You don't want a toy you can't afford to play with.

I gotta agree with halftanked on getting rid of those 305 heads. Had the same basic setup in my '70 Elky and it pinged like crazy once it got hot unless I ran the timing a bit retarded which didn't do anything but kill the performance.

Hey richmondb, I got the balanced kit from powerhouse and it was not to good. I got the one piece rear main seal crank for a 94 block. The first thing I had to do is when I put the crank in, it was hitting the block right where the oil dipstick went in on the oil pan gasket boss. Not a problem to fix with a die grinder and about 1 min. of grinding, other than that every thing else cleared except the piston skirts hit on the counterbalance on about 5 of the pistons. I got that problem taken care of and busted #5 piston. I called and ordered a new set of pistons and when I got them, one already had a hole in it. They shipped me another one but still took a week to get it. Their parts are ok but check everything very well before you put anything in the block. I still run the rods and crank but I went with Speed Pro pistons this time. I think their pistons are pretty much junk and may be seconds or something. I do know one thing, the crank fits in the block without much machine work. As far as power and torque, them strokers sure has got it going on.

Kodiak

So what have you done about the 302 head problem? Get rid of them and find some other GOOD heads?

Here's my plan, because i'm sorta in the same situation as you are. I had a good starting point but until the other day, no direction. But now I think I've decided what i'm looking for.

I'm going to build my 350 so that it gets 1hp = 1cui or at least get it as close as possible. I'll build it so that it is a good, stout running engine. Then spray it. This way, at 350 hp, i'll be able to afford to go and cruise or what not, then when i'm at the track and i need that extra oomph that i'd have gotten from that 400-500 hp motor I can have it. Don't take my advice without some other research and what not first though. Nitrous can be the best choice you've ever made, or it can be the reason that your car is in ashes. It's all about how you deal with it and what precautions you take. A good strong 350 or 383 with a set of good flowing heads and about 50-100 shot of nitrous would get you close to where u want to be without breaking your wallet everytime you go to fill up your gas tank. JMO, and i really hope that i get some feedback on this opinion here because I can't seem to find anyone on here to comment on nitrous use as far as what's safe for a stock block, stock rods and pistons and the different types of upgraded parts.