1989 Gen 1 ~ Interchange Questions

[Whitfield]

New to the site, I've been wrenching 20 years but not much 350 experience.

Thru searching here it looks like I have bought a revised Gen I block..

Engine from a 1989 Suburban TBI 350
going into a 1984 inboard Dixie ski boat (counter rotation).

So far I've found that revised Gen 1 means: 1 piece crank seal, different exhaust manifold bolt spacing at head, different intake bolt (angle in the center holes / not confirmed) hydraulic roller cam/provisions.


My (3) questions are related to building with some of my 1984 parts. My 1984 is 700 hrs but froze and cracked the block / welding brazing repair failed.



1. Can I install non roller lifters and non roller cam in the 1989 motor?
What changes will I need to make?


2. Can I install or modify to install my 84 Gen 1 Edelbrock Performer intake.
What changes will I need to make?


3. Can I run my 1984 Exhaust manifolds, Will the bolt holes line up? Is this a 7 bolt head? If not can I modify it to work with my new $400 boat manifolds.


Bringing motor home tomorrow ~ Working on a build plan today.

[Whitfield]

Answer to question #2 from page 8 here...

Slotting the intake holes to fit the late modle gen 1 heads is a very simple task that about anyone can do.

The four middle intake bolts go in at a 72 degree angle verses pre-87's 90 degree angle.. That's the only ones that need modifying.

The holes are in the same place, just the angles of the the 4 center holes are slightly different.


I've done this mixing and matching many times---especially pulling the TBI intakes off the 80's Camaros and going with a regular intake and carb.

Do not hog out the holes, elongate them to change the angle. A little bit of careful metal removal is all that's needed. When done right, the holes are not wider, just longer.

When using the late intake on early heads, I don't use a wedge washer. I grind the throttle body side of the bolt boss down a little until the bolt and washer fits flat. There is plenty of meat there to work with.

When doing the early intake on a late heads swap, a wedge must be used because you have no boss on the ealy intakes to work with.

[pat mccarthy]

if you change out the timing set roller lifters cam hold down plate push rod you can put a flat lifter cam in a roller block

[Whitfield]

Thanks Pat, It is nice to know I have that option.


As I read thru the volumes of Chevy small block tech (on page 13 now)

I am seeing that placing a flat tappet in a roller block is backwards of the performance trend.

My delima is I need to run my counter rotation engine (marine cam) and I only find (2) cam choices available on the competitoin ski boat parts site. Gen 1 early / and Vortec LS

They offer a roller cam for the later modle vortec motors. Will the Vortec (LS) cam work in the late gen 1 block? (I'm thinking No)

Otherwise I do not find a counter rotation roller cam available for the later modle Gen 1.

[pat mccarthy]

no the ls is not going to work. you could call Howards cams .or Erson cam see if they could grind you rev rot cam in a roller i would look in to that.