4.3 Supercharged Chevy

[Qingdao]

Well... to hell with making a foam copy. This thing is gonna fit no problem. I might have to hack the fire wall some, but not any more than you'd expect.

And OoooHMYgod does the Eaton sit perfect on top of the 4.3.








All I should have to do is hack down the back of the M90 just a hair and tig up a square bore plate. Adapt the M90 for the 4.3 LIM; drop the carb on it and call it a day.




As for the size constraints here is the skinny...




The 4.3 is 22" long from flex plate to W/P... The 2.5 Porsche is about 23 ish (I can't exactly see down in there).

The 4.3 is TALL from the bell housing up its gonna be a whopper of 12" and after about 5 inches forward of the bell housing its gonna be about 16" (cause of the carb). According to my rough estimates that puts me at about right at where the top of the rear storage bin would be. Another words this is gonna fit under the glass.... BUT JUST barely under the glass.

[Qingdao]

Cut down the M90 some more. It almost sits flush on that LIM. Cool cause now all I need is a good 1/2" thick aluminum adaptor plate.





If I'm able to get the carb low enough I'll slap on my buddies old Duel fuel carb hat. How cool would that be having a duel fuel Porsche!!





I also put my vehicle make emblem on it; fits perfect.

[Qingdao]

Damn waiting for pieces. I ordered a 3/4" plate for the adaptor and carb, but it won't be in till Monday. In the mean time I'm twiddling my thumbs.

I did cut out this portion of the firewall. Hoooooo boy what a smell when the grinder met the old sound deadening material. It might also be my grinder is 60 years old and ready to retire.





Do any of you guys know for sure if these are the P/S hoses? They are right behind the drivers seat. They snake under the A/C compressor.

[Qingdao]

I don't really want to flood this thread with needless updates so I've stayed away for the moment. But the engine is out and for sale if anybody wants a boat anchor or coffee table. LOL

Seriously I think it might be a "re-builder". The oil filter didn't seem like it had an excess of metal shavings... IDK Doesn't matter





The Harbor Freight engine hoist which normally is quite inadequate when it comes to length did VERY well here. Just used a long chain and whola the engine is free.









Still waiting for my buddy to finish (or even start) welding my M90 so I can fit it to my 4.3 and get to rebuilding that engine.

[Qingdao]

Well I hit a brick wall. Kennedy doesn't make an adaptor for a 4.3 with an aluminum oil pan for a 5 speed boxster. They wrote me and said something about the starter not having a place with the adaptor plate.

Ah poooo.

I messaged them back to see if I could use an 88-95 4.3 engine. I mean if its the aluminum oil pan that's in the way I can work around that. Shoot mild steel is easy to work with.

I don't see the difference between a 4.3 and a SBC and the difference between the LS and SBC is .400" of bellhousing spacing. So buy an LS adaptor and add .400" of spacing???


One question I do have for any high output boxsters out there; what clutch's are yall running? I'm not seeing too many aftermarket options out there. How much power can the stock clutch hold?

[itsnotanova]

They probably did you a favor. The five speed can barely handle the power from a 2.5/2.7. The five speed won't last that long behind the torque of a supercharged 4.3. You're much better off using a 986 or 987 6 speed.

[Qingdao]

Its cause they use a proprietary starter they make in house and where they put it the starter conflicts with the aluminum oil pan.

I have a friend who, if you get on him hard enough, welds aluminum. Worst case I buy an older 4.3 and use an older block. But more than likely the oil pan is going to be custom.



So 5 speeds can't take the torque?

I have decided to tone it down a bit on the engine. No aggressive cam, light boost, stock or dish toped pistons, and only a 25 shot of nitrous at best.

I'd say 300#s on a good day.