engine block & cylinder head identification

[56hotrodred]

Well it has been a while since I have posted as I have been back at work since the snow melted.

I have been working slowly at getting the body work done with the front and back fenders off, sanded and in at the body shop now. I hope to have them back by the end of summer and then get the box completely sanded down. I am buying an Eastwood soda blaster this summer to help me get all the paint off the cab and the rest of the box.

After trying to work in my un-insulated shop last winter I am also having someone come in and finish portions of my shop interior so I can work in a little more comfort this coming winter. The rest of it I can complete. This will however eat into my limited budget so may delay the truck getting finished for a bit but should be worth it.

In my search for parts this summer I have recently acquired a 327 block (casting # 3858174) that is out of a 1964-67 vehicle rated at 275 to 350 hp and has 2 main caps/bearings.

The heads that came with it (casting # 3917291) are either out of a 1967-69 vehicle and off of a 302 or 327 with 2.02 intake and 1.6 exhaust. There is some confusion here as the casting number is the same as a 350 with 1.94 exhaust and 1.5 exhaust - forgot to write done year. I like the first option but need to know for sure what the heads are from before I commit to re-building.

For those of you in the know does this sound like a desirable engine/head combination for my build? I am doing a resto-mod with my 56 shortbox big back window step side that is sitting on a 1980 1/2 ton frame. I am also hoping to use a Turbo 400 trany that I have eventually putting a gear vendors overdrive unit on it.

Any assistance would be appreciated especially with the proper head identification. As said I think the 302/327 head with the larger intake and exhaust would be the more desirable. The fellow I got it all from says that the heads are out of a corvette and are high performance.

I am going to do some more searching on the heads but I think I am pretty happy with the 327 although I wish it was a 4 bolt main. Should that be of any concern? Was there any 4 bolt main 327's?

Thanks in advance for any assistance.

56hotrodred

[53'gmc]

as for figuring out what heads you have the only way i know of is to measure the intake and exhaust ports if it is the 302/327 head style it will be more desired because of the greater flow it will allow the engine to breath better and create more horsepower without the risks of low flow building, but if you do have the 350 style heads they should flow fine up to 400hp but i would suggest porting and/or enlarging intake and exhaust valve to the desired size if you decide to have them ported make sure they dont make them totally smooth inside because when totally smooth the mixing does not occure and you will have a poor running engine so only smooth out the major ridges and eliminate all sharp bends and corners from the intake manifold to the tip of the exhaust pipe,,,,,,,,,,,,, also i think the 327 hade a 4 bolt main counterpart but i am not positive either way you can have it machined for the proper holes and use the correct 350 caps 'cause a 327 is basically a 350 with a shorter stroke

[56hotrodred]

I have since had a friend in a machine shop measure the heads and they are the 190 intake and 150 exhaust and the old camel backs. He says these are the ones I want to use as the 202's are too thin walled for everyday prolonged use. He suggests boring out the exhaust to 160. The 327 small journal is a 2 bolt main but also a sweet build. He says anybody can have a 350 but the 327's are more unique - also a little more money than a stock 350 crate. I tend to agree and want to eventually get the 327 rebuilt - after he inspects it of course. Most will not know the difference unless they know to look at the vibration dampner as the 327 one is smaller - but I will know. They did not call the 327 the "mighty mouse" for nothing.

Thanks for you comments/replies.

56hotrodred

[Hhan's 57]

I am running the same 327 block in my 57 and have always loved this motor. I last rebuilt my motor in 1986 and at the time it was balanced which made a huge difference. It's a fun and fast reving motor

[56hotrodred]

Sounds like that motor has given you good service. I have always like the older 283's & the 327's.

What is involved in balancing an engine? When my guy says it will cost about $2800.00 to completely rebuild the 327 does that sound like balancing would be a part of the deal? If not how much extra to do so do you think?

56 hotrodred

[Hhan's 57]

With my 327, the rods, pistons and crank were balanced. A balanced engine is smoother at higher RPMs, which is nice on a small block like a 327. I am not sure on cost these days for balancing. In 1986 I paid about $200.

[BigBlocksRule]

Balancing generally costs $150 - $200. It entails making sure the rods all weigh very close to the same on all the big ends and all the little ends. Part if the rod is reciprocating (up and down) weight, as is the piston, and part of the rod is rotating weight. Once the weights are determined, a "bob" weight is added to each journal of the crank to represent the weights of the piston/rod combos. The crank is then spun and balanced similar to the way your tires are balanced at the tire shop. It's probably not worth much (if any) hp, but your bearings will love you for it and it'll make a smooth running engine.
Go for the 327, the crank is forged steel and that 2-bolt block should hold up just fine.

[56hotrodred]

Thanks. That is good information.

56hotrodred