lxcamaroxl

I heard that heads from a 350 will bolt onto a 305. I know that they are a lot better than the heads on my car.

I have found a junk 350 and i want to take the heads off.
The car is an 87-89 Iroc 5.7 TPI

My question is what precautions would I have to take and/or do you have any tips on this subject. I will install these in my 305 if its done right.

I mainly know nothing about heads but im going to try and port them myself. I figure this will be a great way to learn and If I mess up anywhere it will not be too big of a loss.

TheMysticWizard

iTrader: (1)

The only thing that's gonna hurt you is the larger chambers on the 350 heads... the 305 heads probably have a 58cc chamber, while the 350 heads probably have a 64cc chamber. The difference between the two will probably end up costing you 1 point of compression.

The better flow of the heads will have a hard time making up for this loss of compression. The only thing you could do to try and make up for the loss is run a thin head gasket, or have the heads milled down, making smaller chambers. Running a thinner gasket isn't a perfect solution, since you can run into sealing problems with a thinner gasket.

It's up to you, the 350 heads might flow better, but if you already have the 305 tpi heads, you might just want to port them out, you'd probably get better results, since the compression will stay the same, and the flow will increase. Don't get me wrong, the 350 heads will probably flow better, but it's gonna take a ton to make up for the lost compression.

lxcamaroxl

I didnt even think about compression. Damn

I have the TBI heads

F-BIRD'88

Why not just pull the whole motor and take it home.

lxcamaroxl

I dont have that much knowledge of engines,(would be a good way to learn) i dont have that much money either. I did think about it tho.

Gumby

Yep, that sounds backwards.

The trick use to be, get a set of large valve 305 heads, port match and put them on your 350. Though now a days most people just buy better aluminum heads.