hiyosilver

I have the chance to buy a 350 4 bolt up to 85 application . Heres the hitch i would like to put this in my 89 silverado which currently has a 350 throtle body engine that is very tired .Other than the obvious such as side bolt valve covers and mech fuel pump would this bolt up to a 7oo r4 . i know the trans housing is the same but what about the rear main seal 1 piece vrs 2 piece .My main concern is balance of engine.i can buy this motor for a song and a dance brand new in the crate.what problems if any will i have. i know someone has probably done this.one last thing are the heads tapped for external acessories.

Jvette73

I cant confidently answer all your questions but I do believe the thans and flexplate will bolt up to the crate moter no prob. The rear seal shouldnt be an issue. You will need to get the proper carb bracket for the trans TV cable. TV cable setup is important to tranny long life and proper operation. The exaust manifolds may not bolt up. I think the bolt holes in towards on one end of the late model exaust manifold are further spaced. Nothing a set a headers wouldnt cure. I hope someone can concur with me on this cause im not totally sure. I think late model heads like in your '89 have an extra exaust manifold bolt hole on the end of each head.

mountainmotor

You will need to check into a external flex plate for a two piece seal motor like from a 400 also.This I do know a one piece rear seal motor uses a internal harmonic balancer and external flywheel or flexplate.Whether or not the one piece flex plate will work on the 85 I do not know.Edited to add the above post is correct in the added exhaust manifold bolt on the later heads.I have seen this on 1984 305 HO motors.Passenger side center to center is 18 inches while the driver side manifold is 17 1/2.That is manifold bolt centers.Be carefull and double check everything before you buy.


[Modified by mountainmotor, 7:38 PM 12/3/2001]


[Modified by mountainmotor, 7:39 PM 12/3/2001]

hiyosilver

Thanks guys i think i'll pass and just order the correct crate motor from the general .It's my daily driver and i'll leave my hassle energy focused on the vette