2.8/ 3.1 head swap?

[Toaster556]

I'm building a boosted longitudinal 3.1 for my 1992 S-10 S/T project, based around a 1991 Camaro 3.1 block with the forged 3.1 crank/rods, balanced to a set of Wiseco forged pistons. However, I've run into a bit of a conundrum.
I rebuilt my daily's engine (transverse 3.1) last year after it got cooked from a stoned rad, and I noted it had really nice splayed valve heads. The 2.8 has almost Buick Nailhead style heads, and I think the valves are slightly smaller.
Does anyone out there know if a set of transverse heads will bolt up to a longitudinal block? If so, does the Camaro intake bolt up? Thanks all!

[MrPbody]

All of the 60 degree V6s from GM use the same heads. That is, 2.8, 3.1 and 3.4 heads are 100% interchangeable within the same design. The iron heads have a larger chamber, but flow quite well for their era. We build them "up" with larger valves and better springs. The only similarity I can see to the old Buick would be the "zero" valve angle. The ports and chambers were "current" in 1980 when the engine was first released.

We've done many of these engines for both S-10s (and 15s) and Fieros. The iron-headed engine can make 250 HP without MAJOR work. Porting, cam and a good balance, along with larger induction will do the "trick". Edelbrock still offers an intake for them, using either the Rochester that came on them, or with an adapter, a small 4-bbl.

The aluminum heads (the splayed-valve units you speak of) are VERY good heads. If you can move the entire intake assembly "over", and get the injection wired right, you'll realize significant power gains. The water pump drive and plenum may take some creative "enginieering" to make them actually "work". The intake, etc. from the aluminum heads wll NOT fit the iron heads.

Jim

[Toaster556]

So what you're saying is the heads will bolt up, but required the matching intake manifold? It's a good thing I haven't got around to ordering my pistons yet!
I'm using an electric water pump anyways (Scavenged from my aborted joint project with my dad - Caddy 472 meets Cutlass) due to my original planned swap (Supercharged 3.8 Buick - holy crap are those WIDE)

What about the GM Performance parts heads? All my research points towards these heads being the same as the FWD Gen II heads, and I should be able to score a pair through my "connections" at the local GM dealer.
http://www.gmpartsdirect.com/results...ges=1&pkgid=98

I'm using the complete wiring harness from my buddy's 91 Camaro parts car (which the engine was yanked from)

[MrPbody]

Toast...

Pretty much, yes. You COULD use the RWD timing cover and water pump and the aluminum heads together. If you have one of those "remote" water pump drives (Moroso, etc.), it will work well with the RWD unit. It would be a monster to try to make it work with the FWD design. The intake for the aluminum heads is rather large and may create some clearance issues under the hood. I would "scout" a car with this equipment and see what you think.

If you use the aluminum heads, another "trick" is to use the pistons for the iron-headed engine, as the "dish" is smaller, yielding considerably more static compression (horsepower...). Valve reliefs are of no concern until valve "lift" goes over .700", which isn't going to happen here...

You'll save significant money by buying used heads (wrecking yard "specials") as long as they're warranted against cracks when you buy them. Even with a "connection", new heads aren't going to be inexpensive compared. Since you'll want to do some modifications anyway, the used heads can be upgraded just as easily as new ones.

Good luck!

Jim

[Vrtual]

I have a 94 Pontiac 3100 from a Grand Prix. Transverse engine. I am using it in a tractor and would like to put in a distributor and carburetor manifold so I can do away with any computers. Can I use an old 2.8 manifold and distributor for this? Any help would be appreciated.

[MagicRat]

Your 3.1 V6 is a Generation III engine. The carbureted V6 was the old Generation I engine.

The old intake and distributor will not fit the Gen. III engine unless you swap over the iron 2.8 V6 heads as well. Now, if you are going that far, you may as well pick up a complete carbureted 2,8 V6.

What kind of tractor is it? Lots of older, frame-style tractors can accept almost any kind of car engine. Usually guys swap in a carbureted V8.

[Vrtual]

I'm putting the engine in a 782 CUB CADET garden tractor. I know the heads are different in the aluminum version. Mostly the splayed valves and combustion chamber. Can you be more specific to why the intake won't fit? Is it a bolt problem? Do the ports not match? Can it be machined to fit? I don't know a lot about the 60 degree engines.

[Vrtual]

Latest news on putting the 3.1 in the 782 Cub Cadet. So far so good, the tractor engine is mounted in place. I have decided the easiest way to get a distributor to fit is to cut the runner on the intake to allow clearance. I cut a half moon shaped area large enough for the 2.8 distributor to fit. While I had the hole open I bored a 1 inch hole through into the next runner to help feed that cylinder. It won't be a problem on a tractor. I then used a piece of aluminum shaped to fit the hole in the runner and closed up the half moon shap. I will be modifying the plenum to put a carburetor on it next.