Trannie Patterns

[geoffinbc]

Ok I know the 3800 uses the same pattern as the 60* V6's

So thats cool. But does the 3.8L use the same? As in the 3.8L out of old BOP cars? Also Including the 3.8L Turbo engine?

I would think it does but I am curious. Or does it use the Chevy 90* pattern or a totally different third pattern.

[sharkey]

the 660 is its own pattern. ive never heard of the 3800 using the same pattern, but i dont pay attention to the 3800. i can tell you for a fact though that a rwd 3.8 uses a buick tranny, and a 4.3l uses a rwd chevy bolt pattern. im not sure about other 90 degree gm engines like a 3300. i would asume thats the same as a 3800.

[gpse3400]

The RWD 3.8 I believe used a different style from Chev yfor a while, Id say almost what Olds and Caddie used.... I would like to think later on they went to Chevy bolt pattern. All FWD use the same bolt pattern except the Quad4 and damn if know what Saturn does in there spare time...A New RWD 3800 might be the FWD style pattern like a RWD 60 V6.

[sharkey]

actualy, there are lots of varyation in bolt patterns. the 2.0l ohv and 2.2 shares a bolt pattern with the 660 motors. however, a 2.3/2.4l is different, as well as a 2.0l ohc has its own bellhousing.

[geoffinbc]

So know one really knows what the 3.8L is? I know it is not the Chevy pattern. But I cannot confirm if it is the same as the 60* V6 pattern. I know the 3800's use the 60* pattern. Just not sure about the old ones designated as 3.8L.

[bszopi]

I have an old Chevy 3.8 sitting out in the field, next to a 4T60-HD. Next time I'm out there, I can take a look and compare.

[patgizz]

buick rwd 3.8(231) uses the BOP bolt pattern. example: i can take a 200-4R from a grand national and bolt it to my 472 cadillac, or any other pontiac, cadillac, buick, olds V8.

chevy 3.8(229) and 4.3, small block and big block v8, inline 6, use their own pattern different from above and 60*

60* v6, fwd 3800, cadillac 4100, 4.5, 4.9(and possibly the n*), the 2.0, 2.2 use the same pattern.

[skalor]

If it's a 3.8 from any FWD GM car then it uses the same pattern that all 660s use.

[geoffinbc]

Ok thats undertsandable. But what about he 3800 in the Camaro? The only RWD one with the designation 3800.

[Guest]

I had this typed out thisw morning, and then the site went all screwy.

Aight here's the facts....

RWD 3.8 as in what would have come in the early metric chassis G-bodies (late '70s to mid '80s) used the Buick/Cad/Olds pattern, which incedentally were mated to a 200R4 in those cars, at least later on they were.

The 2.0L OHV (I4), 2.2L OHV(I4), 2.5L (iron duke, I4), 2.8L (660), 3.0L (90* V6), 3.1L (660), 3.3L & 3300 (90* V6), 3.4 & 3400, 3500 (660), 3800 (90*V6) all use the GM corporate small pattern, I believe the newly introduced 3.5L and 3.9L VVTI engines use the same pattern.

There are slight differences between FWD and RWD SCP (Small GM Corporate Patterns), some RWD SCPs have the starter on the opposite to FWD, such as Early S-10 and F-body., along with a dowl pin location being moved and a hole that is not threaded on the RWD version where as it is on the FWD version. Then there is the late model RWD 2.2L from the S-10, that uses driver side starter location (would be the same as a FWD engine), but I am unsure of the dowel pin and the threaded/unthreaded hole.

The North star uses a modified small pattern, due to the starter location.

There are actually a few other patterns, like the 1.8L and 2.0L OHC engines, which is different from teh Quad4 engines, and I'm thinking there is yet another pattern, but it's not quite coming to me.

If the patterns of the engines and trannies that you are trying to mate still won't work, there's always adaptors, like those that Transdapt offers, along with a few other manufactures.

Hmm, I'm not sure about the late model RWD 3800, I know I've seen it, just can't pictiure the bellhousing.

[geoffinbc]

Ok well this is all great information.

I was just needing to re asure myself because someone said that he can drop a 3.8L in place of a 4.3L and keep the same tranny. I told him no but he was sure they were the same. I was sure they were NOT the same. So I guess I am right.

I wish there was a chart somewhere that showed what was the same and what was different.... HMMM sounds like a new project for me maybe

[bszopi]

I might be able to get some info from Powertrain...

[skalor]

The 3800 SII that's in the F-bodies use the 660 pattern as well. I helped my brother swap in a 3800 SII from a camaro into his '92 S-10. He runs the 4L60E that came on the L36, and it's a great tranny since there are a ton of upgrades available since the same tranny was used behind LT1s and even some LS1s IIRC. He has had a best of a 14.8 @ 91 with a 2.1 60' thanks to some homemade Caltrax type traction bars. He runs a zexel LSD in his stock rear with 3.73s and 245/50/16 Falken Ziex. We're planning on adding a turbo this winter and we're hoping that with drag racials we can squeeze 12s out of his stock L36 with 10 psi. There are quite a few turbo L36 GP guys that have run 12s running 10 psi non-intercooled. So, we should get there no problem as long as he can get some traction.

[geoffinbc]

Alright guys I am doing an GM Bellhousing Bolt Patter FAQ. So I am enlisting some help.

The OHC 2.2L in the cavaliers Use what pattern? Im guessing teh same as the 660 also what abotu the new Ecotec
I know the Quad Cams are different aswell as the Isuzu 1.8, 1.9 and 2.0L

[Guest]

UMMMM, you mean the OHV 2.2, right? That would be the FWD 660 (Small corporate) pattern.

The OHC 2.2 would be the ecotech, which I am not sure what they use for a pettern.