Manual tranny for 81 Malibu cross?

[robertisaar]

probably the 4.3 had vortec heads. which would be in improvement in power and economy, but if you can't fit them, oh well.

[rgaz]

When I measured it with the heads on, the heads were a different shape or had something that would cause an interference. I can't remember which it was, it might have been the height or something else. I ahd the 3.8L already sitting around anyway.

[robertisaar]

thats odd... the only difference between the Chevrolet 3.8 and the 4.3 is that the 4.3 has the bore of a 350, and a 3.8 has the bore of a 305.... it should be the same block externally...

[faster7]

Thanks, so any 80-90's year is fine? I looked at the 4.3, the engine width angle and height was a problem. In the app I am looking at the space between the shock towers is tight, real tight. There used to be a 1.5L I4 in there that sat much lower.

Thanks,
Randy

Yes, any 80's/90's. Still trying to nail down which flywheel you will want to run.

I bet if you take a tape measure to yours and to a 4.3 you will find that they are the same, and also that the bigger bored 4.3 weighs a bit less.

[rgaz]

Yes, distributor in the back= chevrolet V6, SBC bolt pattern. So I'd be looking for the complete T5 setup from a V8 camaro. I'm not sure about which flywheel you will need though.

Honestly though with that motor.... as common/cheap/BETTER as the 4.3's are, I'd find a 4.3 to start with.

Thanks, so any 80-90's year is fine? I looked at the 4.3, the engine width angle and height was a problem. In the app I am looking at the space between the shock towers is tight, real tight. There used to be a 1.5L I4 in there that sat much lower.

Thanks,
Randy

[faster7]

Man you rock. This makes perfect sense. My 3.8l has the dist in the back so from your post I can assume that I can fit any 70's model chevy manual? So I can go find a old S-10 or nova manual? Ok, considering I have a 3.85 rear diff ratio, which car/truck manual would give me a good street combo with highway capability? I.e. which car/truck would be the best combo.

(If you can answer this, life would be good).

Randy

Yes, distributor in the back= chevrolet V6, SBC bolt pattern. So I'd be looking for the complete T5 setup from a V8 camaro. I'm not sure about which flywheel you will need though.

Honestly though with that motor.... as common/cheap/BETTER as the 4.3's are, I'd find a 4.3 to start with.

[rgaz]

Back in the day, there was two different 3.8's - one Chevy production, one Buick production. Most of the '81 Malibu had the Chev production engine. If it's the Chev engine, the dist is in the back, same as the original small block. This engine was the early design that grew into the 4.3. It has the same bellhousing bolt pattern as the early Camaros, Chevelles, Nova, etc., so the trans combo's are endless.
The Buick 3.8 is the same engine that powered the GNs, but have the BOP bellhousing pattern. The dist is in the front. You can use the same transmissions, but you need a different bellhousing. D

Man you rock. This makes perfect sense. My 3.8l has the dist in the back so from your post I can assume that I can fit any 70's model chevy manual? So I can go find a old S-10 or nova manual? Ok, considering I have a 3.85 rear diff ratio, which car/truck manual would give me a good street combo with highway capability? I.e. which car/truck would be the best combo.

(If you can answer this, life would be good).

Randy

[turboD]

Back in the day, there was two different 3.8's - one Chevy production, one Buick production. Most of the '81 Malibu had the Chev production engine. If it's the Chev engine, the dist is in the back, same as the original small block. This engine was the early design that grew into the 4.3. It has the same bellhousing bolt pattern as the early Camaros, Chevelles, Nova, etc., so the trans combo's are endless.
The Buick 3.8 is the same engine that powered the GNs, but have the BOP bellhousing pattern. The dist is in the front. You can use the same transmissions, but you need a different bellhousing. D

[LeftVentricle]

In a Spitfire? Hell yes. Yeah, the 3.8 is rated 110 hp, but it makes a buttload of torque, so that'll be plenty fun. Thought you were gonna do this to the Malibu, which is why I said to V8 it up. In the 'bu there's not much reason not to, since it's a cheap and easy swap.

[rgaz]

Custom I can handle. I checked the Wiki BOP search as well and found two articles that had conflicting information, so I am trying to confirm. The BOP as listed has a whole ton of autos and as you found only one 3-speed option as noted. This is not the route I am going. It also suggest that the BOP is for 82 and up and the car i got it from was an 81.

It sounds like you guys suggest finding a V8 4-speed and work on something custom. I was jsut hoping someone would say "go find a 91 4-speed camaro with the 3.4l or the 3.8L, it will mate perfect." Since no one said that, I will take a template of my auto bellhousing to the junkyard and play "let's match a bellhousing" with any GM manual I can find. i was trying to avoid that, but it sounds like my best plan.

As for the performance comment. Yeah, I know, but what I didn't tell you is that I am putting it in a 1973 Triumph spitfire. I expect toal curb weight to be on or about 1700lbs with my mods so 110 HP will be plenty for a fun RWD two-seater. V8 has been done and it isn't sleeper. After I get the suspension where I want it, I will rebuild the engine and set it up with a custom EFI. From there if it really isn't fun enough, I'll add a custom T3/T4 turbo running a modest 7psi with intercooling and dyno-tuned EFI which I expect to pretty much be the limit of the chassis and drivetrain (basically GNX-level swap). Of course that is only if I get bored.

Really, my goal was to make it a sleeper ( A REAL sleeper) fun to drive RWD convertible with the reliability of one GM's best designed engines.

I'll try and be on the board as I go and keep you guys updated. Wanna see pics?

Thanks,
Randy

[WrathOfSocrus]

The older 3.8's had a BOP (Buick, Oldsmobile, Pontiac) bellhousing. The easiest route would be to find a BOP manual trans. A V8 or V6 BOP trans should work. If you can only find a chevy then you could look for an adapter plate. They also have aftermarket bellhousings with both the chevy and BOP bolt patterns but the one I see at McLeod does not have a hydraulic slave cylinder bracket. The first link that came up when I googled 3.8 bellhousing had all of the answers.

I checked car-part.com and they show over a dozen variations of auto transmissions for cars with that body but no manual. Wikipedia says the only manual available that came with that body car was a 3 speed. You will probably have to eviscerate one from an older BOP V8 car and make a custom mount. If not then I'm sure there are plenty of 4 speeds in 2WD trucks that can be cannibalized and made to fit. Either way will probably invole some amount of custom work.

[robertisaar]

I'm saying that it's possible to make the 3.8 fast, just not in its current, probably carbureted form. Unless he's gonna do the sensible thing and small block it.

of course its possible to get it fast, but not as economically as going the SBC route, i will agree with that. turbo small blocks are also fun...

[LeftVentricle]

I'm saying that it's possible to make the 3.8 fast, just not in its current, probably carbureted form. Unless he's gonna do the sensible thing and small block it.

[robertisaar]

what do you mean by mods? i believe it was SFI, and it was rated at "276"HP and 350 TQ. i believe that 276 was probably a lot closer to 350 considering what kind of timeslips they turn in. it also depends on year too. i think the 85 and earlier GNs were NOT intercooled, while the 86-87 GN/GNX were intercooled. and the corvette at that time didn't even make that much. the L98s only made 250 at that point.

the syclone/typhoons were also badasses and ate the ZR1's lunch when it came to the 1/4 mile.

but i should stop talking, the last time i started talking about the 90*V6 motors, Ben decided to lock the thread

[LeftVentricle]

the manual tranny from the v6 camaros should bolt up(at the bellhousing anyway) i know the newer 3800s have the same bellhousing pattern as every other FWD V6. the t5 from the camaros have unique cases that allow them to bolt to the V6.

but honestly i wouldn't touch that 3.8, it makes what 110HP? if you're doing it for performance, you're heading down the wrong road...

What sort of modifications did GM do to the Grand National et al? It made more power than the period Corvette, like 280 hp.