alright, my 350 is siezed with rust. i am totally disgusted with the late model blocks, i have had nothing but touble with the motor. i have a 305 from an 85z28. the problem is that i bought an aftermarket intake for the new model heads. It is the holley street dominator intake and it was like $160. is it possible to machine the intake to work with the older 416 castings i have? or do i have to spend another $120 on a new intake? i am very discouraged and the possibility of me saving at least some of the stuff from the origninal build is encouraging. if i can fix it, how should i go about doing it? something about special angle washers?

 

The major difference is the angle of the two center bolts into the heads. 1987 and later heads have these two bolts drilled and tapped at a 72° angle, while older heads have these holes perpendicular (90°) to the machined intake flange.

It is more common to convert an older intake to the newer heads by slightly elongating the two center holes and installing tapered or self-centering washers. I suppose just the opposite could be done by elongating the holes in the other direction and installing the washers to accomplish the same thing (or machining the intake surface square).

You can use wedged structural washers, which typically have a 15° angle to match the flanges on structural steel beams. This will require you to slightly grind or file them for a perfect fit. You can even get them in aluminum, carbon steel, or staqinless steel:



Or you can use conical self-centering washers that will distribute load at any angle up to 30°.



There is a little more detail in this thread: https://www.thirdgen.org/techbb2/sho...hreadid=168616

 

why not clean up the 350?

 

cause it cost to much to do. if i do rebuild the motor, i would do it "right the first time", meaning, good rods, forged pistons, and everything. i have a 305 at the house already, and i KNOW that it works, so i will put that in, probably sell the 350, cause i have a 355 block in the shed i will clean up and have cleared for a 383 build. it's all a matter of doing things once.(even though i will have done two motor swaps by the time it's all said and done) if i put the 305 in, all the parts i put on it will go to the 383(ie cam that's in it is a blue racer, roller rockers ect.) cause the 355 block i have is pre-86 as well. it's complicated to explain over the internet, but i got it figured out in my head.