motor questions,chevy experts needed?

Question

ok i recently had a motor put in a 86 chevy 4x4 truck, it had a 305 and i had a 350 put in, the motor is carb, when the motor was changed he had to get a new intake manifold and valve covers, my valve covers that were on the 305 have the 4 bolts on the outside but now on the 350 they have 2 bolts down the center of the covers, with that being said is this motor really for a 88 and up model car, and if so isn't there a difference in flywheels, i thought the flywheels for 87 and below were one style and 88 and up were weighted flywheels, plz tell me if i am right, also what are some other ways i can tell what this motor is for, and one last question the motor has square ports and my headers are of course round, my header gasket should be sqaured not round correct, plz give me as much info as possible

also which gaskets are better copper or alum. for headers

Answer 1

It just might possibly make a good boat anchor

Answer 2

All 283,302, 327 and 350 Chevrolet's are internally balanced. Only the 383's and 400's are externally balanced The vortec cylinder heads all have four bolts across the center of the valve cover. There is however one cylinder head with four bolts across the middle which is not of the vortec design. That's part number 10159552. The vortec iron heads are worth 20 - 30 free horsepower. Don't worry about header gaskets you'll see that they lay on the outside perimiter of the port and will provide adequate sealing. All vortec heads have plenty of meat around the exhaust ports to provide the seal your looking for. When selecting headers resist large diameter primaries. A 1 5/8 equal length with small collectors is hot for street use. Actually a tri-wy design (Headman) is best if you have an automatic trans.They'll keep the velosity of the exhaust gasses up which will aid scavaging the next exhaust pulse.

Answer 3

To answer some of this best of my knowledge all the flywheels are weighted, this balances the flywheel wheel out. Now for the center bolt valve covers, they came on the newer eightys and up. But if i recall right the heads can interchange with the older blocks with a different intake. Id recommend cooper gasket.

Answer 4

Your flywheel and valve cover r the same .....they r internally balanced...the 400 is the only one that uses a weighted flywheel. However your gaskets are the only ones that will make a difference to your exhaust. You should go with square because they have to mate the block instead of the header.

You can purchase a GM bible and see the casting numbers.

Answer 5

yes you are right on flywheels ,88 and newer have weights ,smaller bolt pattern on the crankshaft .and the block has a one piece alum. crank seal. most Chevy blocks have an ident. stamping on the right front of the block where the head gasket would sit .two row of numbers and letters call your gm or salvage yard with alphabet only. they can tell you year and type car or truck motor was from