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Different Gen's

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Old 01-07-2010, 10:21 PM
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Default Different Gen'*

So I've been getting into the upper end of my car getting my upper intake conversation and cam on the ball. But I'm out of the loops what is the different gens.

I mean I know I need a gen V to Gen II adapter I see people selling Gen V LIM and Gen 3 LIM'* but no 4'* or 2'* I see some 1'* SO what is up with all of this?
Old 01-07-2010, 11:06 PM
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So...as I understand....

The Gen 2 SC is also known as the Eaton M-62 (62 referees to cubic foot minute of air movement per a stroke). It was used in 1992 and 1993 cars.

The Gen 3 SC is also known as the Eaton M-62. It was used in 1994 and 1995 cars. It has epoxy coated rotors and a larger inlet diameter.

The M-90 (90 referees to cubic foot minute of air movement per a stroke) was introduced in 1996 for the debut of the L67 Series 2 engine.

The Gen V Eaton is a more efficient M-90. It has tighter tolerances.
Old 01-07-2010, 11:51 PM
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they also say a ported M90 would come very close to a Gen V
Old 01-08-2010, 12:02 AM
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Originally Posted by SAMzGXP
they also say a ported M90 would come very close to a Gen V
Put a ported and polished Gen V can't be touched!
Old 01-08-2010, 06:40 AM
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The two M90 superchargers that a Series II 3800 can use are a Gen III and a Gen IV. There were other versions of the M90, but they weren't all available for us. The M90 has been used on other cars, including for some reason those weird Fords. I believe mostly the Fords used the 2nd and 4th generations.

These superchargers look kind of different with the main differences being the outlet shape, all 3 bolt patterns, intake length, snout length, etc. The Gen III M90 was supposed to be the last one for the 3800 because a larger-displacement 3.5L Shortstar, in 3.7L form, was supposed to replace the 3800 engines. When that project was scrapped, the Gen IV M90 came out and was paired with the Series III 3800. In between these two generations, a 4th gen M90 came out but wasn't used by GM IIRC.

The Gen 3 M90s also differ because they were used both for the 3800 and the Ford 3.8L engines in the Thunderbirds. These aren't interchangeable. As for why the adapters work, GM has been using the same throttle body bolt pattern for all their supercharged/naturally aspirated engine setups. The Series 1, 2, and 3 3800s all had the same bolt patterns for their supercharged and naturally aspirated versions. The inside of the throttle body for the NA version changed for the Series II, but GM went back to having the same throttle body for both engine types in the Series III engine. So if an L67 owner were to put an L32'* supercharger on his car, he'd have to use an adapter. This same adapter works for the L26 UIM because it is an adapter from the Series II throttle body to the Series III bolt pattern.

To answer simply, the engines which use the M90 are Series II and Series III. Because of Magnusson (supercharger guys) and GM (3800 guys) developing their superchargers and engines at different rates, the engine series and supercharger generation numbers don't match up. The generation numbers are much like engine numbers, but GM only developed 2 modern-style 3800s before cutting them out.

Also, the M62, mentioned above, has gone through almost as many generations. The latest generation is a Gen IV, IIRC, which is used for the supercharged 2.0L Ecotec engines in the Cobalts and Ions. The Gen III M62 was used on 94-95 Bonnevilles, the Gen II on 92-93 Bonnevilles, and the Gen 1 wasn't made available to the 3800.
Old 01-08-2010, 06:48 AM
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I'm unsure where to start here.

....I'm gonna go pee. BRB


First off...there is a lot of info about the chargers and it can be confusing. Like Rad stating above that there is a Gen iV or 4 supercharger on a GM 3800. He ooopsied and typed it wrong, we all know he knows it'* a Gen V or 5. Right now he'* smacking himself for that mistake. There are both M62 and M90 Gen 3'*. This can add to the confusion.

The Gen 2 M62 appeared on GM cars in 92 and ran from 92-93. Park Avenue, Bonneville and Riviera. This supercharger had no coating on the rotors and a 2.5" pulley stock and thermal coating on the exterior body of the charger.

The Gen 3 M62 replaced the Gen 2 for 94-95 years. This supercharger looked similar to the Gen 2 and had coating on the rotors. The coating on the rotors increased efficiency and the pulley was changed to a 2.8" diameter. There is external coating on the Gen 3 M62 as well as an external fin difference from the Gen 2, I forget which is which though.

The Gen 3 M90 took the M62'* place on the 3800 starting in 96 with the new motor design for the Series II. In 96 the supercharger body was coated with thermal coating like the 92-95 M62'* and had a vacuum tree near the throttle body end of the charger. 97 stayed the same except the exterior thermal coating was not present on the charger body. In 98 to current the vacuum tree was deleted and no thermal coating. The Gen 3 M90 has a 3.8" pulley diameter.

The Gen V M90 appeared on the scene in Grand Prix'* beginning in 2004, this redesigned M90 had a more efficient airflow and longer rotors than the Gen 3 causing it to run much cooler than it'* predecessor. The Gen V bolts right up to the LIM of a Gen 3 except for a slightly larger outlet opening. Different throttle body bolt patterns make an adapter plate necessary to swap from Gen 3 to Gen V. The Gen V retained the 3.8" diameter pulley as well.

The M designation is the amount of cubic inches of air per revolution that the charger moves. An M62 moves 62 ci of air per rev and an M90 moves 90 ci of air.

Ok.. with that out of the way. Let'* talk about throttle bodies on the Series 2 and 3 as I'm not 100% sure on the earlier stuff and wouldn't want to put up bad info. The 96 throttle bodies for both L36 and L67 had an extra vacuum port on the side for the 4T60 vaccum modulated transmission. In 97 the L67 no longer had the port as it moved to the 4T65 and the L36 no longer had the port when it was moved to the 4T65 transmission in 1998. In 99 the throttle body on both motors was redesigned slightly to have a maf w/o a metal post in the center of the TB. This allows a little more airflow. The Series 3 motors both use the same TB spacing and 4 bolt pattern, therefore when you want to make an adapter for either, it will be the same design.
Old 01-08-2010, 06:50 AM
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Go Bill!
Old 01-08-2010, 09:39 AM
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I have noticed the TB'* to be different between 94, 95 and 96. Seems 95 was a lone year for the TB. The 95 MAF mount has provisions for 3 screws, while the 94 and 96 have 2.
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Old 01-08-2010, 11:31 AM
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The castings should be the same 87-91, 92-95, and 96-2005 with little differences like apparently MAF screws and definitely MAF posts like in the 96/97 throttle bodies. The insides are different for the 96-03 throttle bodies between the naturally aspirated engines and the supercharged ones.
Old 03-02-2010, 06:38 PM
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I have to admit I am a bit of a lecher, (I own an 1992 Olds Touring Sedan SC not a lot of info on this car) I did fall in love with the 89-91 SSE'*, love the 92-95' SSEi'*, other than the Series 2 supercharged in the 96-99 I not a big fan of them, love the latest gen, the Northstar may have had the power but ask an Aurora owner how much fun $$$$ they can be to fix!

Getting to my point I understand that the 93-94 changes in the 3800sc offered a 20hp gain and an increase in torque, partly due to the gen 3 M62, as much as I would love to do a Series 2 swap (The wife will kill me for even thinking of spending the money) could I bolt a Gen 3 on the Gen 2 car? And if I could would it be worth it?

Thanks


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