My son has a 1984 Firebird that has had the computer eliminated to run an older chevy V8 with carb and HEI distributor. We have a 1993 GMC truck 350 engine that was fuel injected and computer controlled distributor and an oil filter with cooling lines . We want to eliminate all of these things and put all of the parts from the older engine . ( Carb and intake , HEI distributor , and put a standard oil filter on the engine ) and use this engine in the car. Are there any differences in these blocks and heads from the older engines ? Don't want any surprises . Has anyone made this conversion ?

 

They're both Gen 1 engines, the parts are interchangeable. The one thing you'll run into is the 2 inner intake manifold bolts on both sides of the 93 engine go vertically into the heads as opposed to the rest of them, and all on the older engine, going in on an angle. You can "fix" this on the old intake manifold by drilling those holes vertically. The bolts will only catch on the one edge of the manifold, which works, or you could make angled spacers. The other difference is the center valve cover bolts on the 87 and newer engines vs your current 4 bolts on the perimeter lip.

 

We noticed the valve covers bolt on different but hadn't seen the difference in the intake manifold yet . I'll take another look . Thanks for that heads up.

 

The angled intake bolts are at a 90 degree angle to the heads. The center ones on your 93 are 72 degrees, an 18 degree difference. Those bolts aren't straight up and down, but you'll see it.

 

I checked out those bolts . I would have never noticed it since it is so slight . I was wondering if someone is making an aftermarket intake manifold with the proper angle on those bolt holes. Maybe someone else has bought one and will chime in . If not I will alter the holes . Another concern is the oil filter. The engine came out of a heavy duty 3/4 ton truck with a factory adapter for an oil cooler and lines . Will it accept the bolt in adapter for a screw in oil filter ?

 

Edelbrock, for one, makes intake manifolds for that engine. Unless you don't like the intake you have and want something different, I'd just ream out the holes with a drill to give them a new angle.
For the oil filter, is what you have the sandwich adapter with in & out lines, and a spin on filter below that? Or do you have a remote mount filter?

 

Yes it is the adapter right at the normal filter location with the in and out lines . When we removed it there is no spin on adapter but the mounting holes for the adapter are there if it takes the usual adapter. It looks the same. As for the intake manifold we will probably just taper the holes . The block off plate for the fuel pump is there . Not sure if it would already have the concentric for the push rod . I'm thinking it should be there already and just need the push rod. Other than those things I don't see any other problems.

 

You can also find stock intakes that will work. GM made the change in 87, there was still a lot of larger trucks running carbs in 87-88, heck I think there was a 305 Camaro carbed in 87 that would work. Also I think there was someone selling the wedge style washer to make it work right.

 

Thanks that is good to know.