Hey guys, i need your help!

I have a 350 that i got from a friend for free and wanna replace it with my 305. The only thing is...i dont know much about engines! The block I have is a '94 350 block, "hecho en mexico" and is a 2 piece rear seal. Thats all i know. Whats the best thing i should do to make the engine run at its best? What should i rebuild? replace? What are the best specs for what? I would like to get at least 350 HP out of the engine, and also try not to spend an arm and a leg on everything. I appreciate your guys help and will keep you posted on whats going on. Thanks!!!!!!!!

 

first thing would be the heads.....then the intake and cam...emmissions in cali will restrict you on your choices....

 

Cam would be first on my list.

 

If you are rebuilding it completely then take the whole thing apart. Take the block to the machine shop and bore it out .030 over. Have it magnafluxed and align bored, and hot tanked. Then have the crank polished or turned 10/10. Have the rods sonic checked and straightened.Get some 9.0:1 or 9.5:1 pistons and put the short block togethter. Then have the heads rebuilt with a three angle valve job and new springs, locks and retainers. Have the heads resurfaces and magnafluxed, hot tanked. You will have to use an emissions legal cam. Oh yea, don't forget to have the cam bearings changed by the machine shop. Then when this is done, put the long block back together. Don't forget to use a high volume oil pump. When this is done you will have to pick out your intake system. You have to make sure that it is 50 state legal. Then put the accessories on and water pump and other misc. things and you should have a pretty powerful smog legal engine. Now, this is just what I would do.

If you want to know a sure fire engine check out the chevy high performance magazine. They had an article in there that said how to build an emmissions legal 355. It was pretty powerful too, and they put it in a thirdgen. If you can't find the article, then tell me and I will scan it in here for you. Good luck.

 

Free is good
OK..... you've got conflicting statements here. If it is a '94 block, it should be a 1 pc. rear main seal. Get the casting number off the block and go here www.mortec.com/castnum.htm and look it up. The casting number will be where the bellhousing bolts on.


As far as the rest goes, do what bes217 says except the high volume oil pump. That's not needed on the street and actually uses a few horses to move more oil that doesn't need to be moved.

For just a few dollars more than what it would cost you to get those heads rebuilt, you can get a good set of aftermarket heads. I wouldn't waste the money on rebuilding them.

Find the casting numbers (under the valve cover) of the heads and use the link above to check those also. More than likely they're either 14102191 or 14102193. Not great heads for performance.