Whats the main difference between the 305 heads and the 350 heads. Probably air flow. Does anyone know the spring seat lbs? The thing is that I have a 350 Crate TPI and I dont know if the guy who switched the engine before me used new 350 heads or the old stock 305 heads. I was going to have the heads redone but looked into it and noticed I can get new heads for $180 each while I would be paying for them to get redone for $175 eace. Get what Im saying. Is it worth buying new 350 heads from AutoZone with the springs and valves and all instead of having my maybe 350 heads redone?

 

the 305 heads have different water ports then the 350 so they ont work on a 350

 

The coolant ports aren't THAT different.....just slightly bigger on the 305 heads. You can bolt them on and it'll work fine. Compression will be nice and high but the intake/exhaust flow will be cruddy at best.

The 350 heads generally have bigger runners, bigger valves, and bigger chambers. To be any more specific than that you'll need to know the casting number of the heads. FWIW all you need to do to find out for sure what heads you have is pull one valve cover. The casting number will be between the 5&7 cylinders on the driver's side or the 2&4 cyl on the pass side. Get the number and go to Mortec.com and match it up to see exactly which heads you have.

 

Thanks alot man. Good site. Im gonna bookmark it. Didnt narrow it down though..haha,.....I guess its good for both 305 and 350 blocks.

14102193...87-up...305/350......1.94"/1.5" valves

 

Those are terrible heads, the TBI heads.

Go to the junkyard and for about $30 get a set of 601, 416 or 083 305 heads. Then do them up according to the instructions at the end of my sig.

 

I agree...the swirl-port heads aren't even worth freshening up. I'd try to find a set of Vortec truck heads and get them milled and have bigger springs installed. Stick a Performer AirGap intake on them and a TBI-4150 flange adapter and you'll make good power. It may even fit under the stock hood with a drop-base air cleaner.

 

Im trying to go cheap at the moment. Do you think its worth buying the 92' 350 stock heads? Its only about $350. I cant afford a different intake or anything right now so I need to go cheap

 

Thanks alot for this info. Good stuff.