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Login to post Forums » Grassroots Motorsports » M62 Snout interchange Question

July 2, 2011 2:09 p.m. dean1484 SuperDork

I have an M62 from a c230 it had the large clutch type pulley on it that I did not want so I fabricated a new pulley to run on the existing bearings. It works but is ugly.

I was wondering if anyone knows if the front snout from a GM eaton M62 will bolt up to the back half of a M62 from a c230.

The reason I would like to do this is that the c230 unit has a very clean intake and exhaust ports. The unit looks to be mounted in a manor similar to an alternator or AC compressor. Where as the M62 from the Pontiac has a huge flat plate cast on to the housing on the bottom that mounted to the motor. This makes adapting it to other uses more challenging as the mounting bolt are integrated into the plate making it almost have to mount with the exit port down or to the side where as the c230 unit exit port is on top with respect to the mounting holes that are cast in to the housing.

Here is the Pontiac M62

I have a C230 M62 like this but without the large clutch pulley

Anyway does anyone know if the snouts interchangeable?
July 2, 2011 9:35 p.m. ditchdigger HalfDork

I have both pieces on the shelf, but no time in the next couple of days to attempt it for you. I am told that they are a direct swap, but I have been told lots of things that weren't totally true before. They sure look the same though.

If I finish up the current project early enough tomorrow I will try and snap some pics for you.
July 2, 2011 9:58 p.m. MrJoshua SuperDork

IIRC Eatons site (magnusson) made it look like you could order different length front sections without issue.

To tag a question on to your pulley question: can you retrofit a vacuum bypass system like used in the GM version?
July 3, 2011 7:58 a.m. dean1484 SuperDork

Mr Joshua wrote: To tag a question on to your pulley question: can you retrofit a vacuum bypass system like used in the GM version?

Mangstrum (sp) Sells a valve that you can use that will bypass the SC when the intake go in to vacuum. I have one somewhere that I got from a fellow GRM member that needed the diaphragm replace. I ordered the new part and repaired it. It is a very well made piece. There is also a bypass valve that you could use from a 951 that is probably easier to plum in. The Vortech systems use a similar (if not the same) valve as the ones in the 951.
July 3, 2011 9:50 p.m. ditchdigger HalfDork

Ok so the housings are identical so the snout does swap over.....but it won't work.

The Mercedes unit has the splined shaft to spin the charger and the GM piece has the 3 studs that connect to a coupler. Looks like you will need a whole charger
July 5, 2011 5:09 p.m. dean1484 SuperDork

So if I got a complete charger and swapped the snout and the gears it sould work? eBay has the Pontiac M62's cheap as of late. In other-words could I swap the housing that covers the impellers?
Feb. 17, 2012 2:16 p.m. dean1484 SuperDork

Bringing this back from the dead.

As noted above the internal gears / connection to the snout is different. BUT could you go the other way and swap the back housing from one to the other? In other words are the screws inside the housing the same. Basically I want the front snout from the GM unit with impeller housing of the MB unit.

I think I have found a good deal on a GM M62 so this is percolating to the top again.
Feb. 17, 2012 7:55 p.m. Vigo SuperDork

Basically i want a clutch setup on the front of the existing long snout of my supercoupe m90.

but regardless, carry on.
Feb. 18, 2012 11:21 a.m. dean1484 SuperDork

No real reason for posting other than to vent a bit.

Wednesday I go down and find a really nice M62 on a Buick Riv in the Pick and pull. It looked new. The snout was really tight and the unit was really clean and spun really well. I told the guy that I always deal with at the P&P that I would be back Saturday to get it. He says great I will pull the car out and have it off to the side for me to work on.

I go today and see the guy and ask where the white Riv is . The other guy at the counter gets this 1000 yard deer in the headlights look. Both of us say in unison say "WHAT". In a sheepish voice he said that he crushed it this morning. "I thought it was pulled out for crushing" (It was a very complete car in very good condition). So I am SOL as they don't have another one. As I walked away I could here the yelling in-sue.

I actually know there system. There has to be a big orange X painted on the roof. This signifies that the are is to be pulled form the rows and crushed. Unforchantly the car crusher is about 50 yards from the area where cars are pulled to when they are removing motors etc. On weekends if it is a significant item to be removed or I need access under a car they will pull a car for me and put it over there so I can access things better and I also have access to torches and air tools if I need them. Yes this is special treatment but I have been doing business with them for many years and generally don't haggle and wine about prices and there rules. I always ask first and follow the rules to the letter when I am in the place.

So I am now waiting until they get another one.. . ..

Can anyone get one of these out of there local P&P? I saw a thread a while back that yards were charging $75 or so for them? I would be willing to pay for one and obviously the shipping if some one could get one (an M62 from a GM)
Feb. 18, 2012 12:38 p.m. mad_machine SuperDork

ouch.. that sucks... so close
Feb. 18, 2012 12:41 p.m. 92CelicaHalfTrac SuperDork

If i wasn't so sick... i'd go and grab one for you today.
Feb. 18, 2012 1:05 p.m. dean1484 SuperDork

No rush but if you had the time it would be greatly appreciated. I have a project in the works that this is an intrical part of.

And if you have the choice between a ok one for X$ and a really good one for X+$25 go for the ladder of the two choices.
Feb. 18, 2012 1:08 p.m. mad_machine SuperDork

I get the feeling this is going to be an interesting plan. Since they stopped production of the sueprcharger kit for the BMW m44 engine, I have been wondering what it would take to "roll my own". Any ideas on the weight of the m62?
Feb. 18, 2012 3:08 p.m. 1slowcrx HalfDork

mad_machine wrote:

I get the feeling this is going to be an interesting plan. Since they stopped production of the sueprcharger kit for the BMW m44 engine, I have been wondering what it would take to "roll my own". Any ideas on the weight of the m62?

M52/S52...
Feb. 18, 2012 3:11 p.m. mad_machine SuperDork

I like the weight balance of my ti with the four. There is close to a foot of space between the pulleys and the radiator, so it is a very neutral handling beast. The only way I would consider a 6 would be the all aluminum 3.0 out of the z3
Feb. 18, 2012 4:00 p.m. Knurled Dork

Vigo wrote:

Basically i want a clutch setup on the front of the existing long snout of my supercoupe m90.

but regardless, carry on.

Seen Mad Max too many times?

Really, the internal bypass unloads the blower plenty, and is pretty idiot-proof. Mercedes clutched the blower because I guess they don't like idiot-proof, it's too simple.
Feb. 19, 2012 9:16 a.m. Vigo SuperDork

my supercoupe m90 doesnt have an internal bypass, but if there isnt an easy clutch solution (and maybe even if there is) i am definitely building an external one. Still working on the cheapest valve for that purpose..
Feb. 19, 2012 9:42 a.m. dean1484 SuperDork

I was at the P&P yesterday and there is an Audi a4 turbo that has the bypass valve still on it (the same unit used on 951's and the same unit used by Vortech in the supercharger kit that I pulled off my wife's mustang). I bet I could get it for short $$$$ or even free. There was also an IC there that I wanted but did not have the time to get. Again obtainable for short $$$$.
Feb. 19, 2012 1:31 p.m. Vigo SuperDork

Any kind of thing that might be called a 'bypass valve' on a turbo car is going to need a much higher pressure differential to overcome the internal spring, than what is available between the two sides of a valve that 'bypasses' a supercharger at light loads.

The bypass valve in a GM unit is basically a throttle plate. On my m90 app (chryco-adapted mitsu 6g72) i am thinking about just using the stock TB as a bypass and routing a pipe from it back into the intake piping of the m90. There will be a much bigger non-stock TB being used as the actual throttle now.
Feb. 19, 2012 5:17 p.m. Knurled Dork

In reply to Vigo:

Sounds like what Volkswagen did on the G60 engine., which like the Mercedes, put a supercharger upstream of the throttle body. Goofiest throttle body you ever saw, if you'd never seen one. Standard contemporary VW double-throttle unit, with a linkage to a second throttle plate that worked inversely to the main throttle, this bypassed the air back to the blower's inlet.
Feb. 19, 2012 7:27 p.m. Vigo SuperDork

That does sound like a weird system. My situation is pretty unique because the motor in question has a completely flat top to the plenum to bolt the m90 to. It would actually bypass or be 'downstream' of the TB that way. The stock TB would just be removed and blocked off if i didnt want to use it as a recirc.
Feb. 19, 2012 7:53 p.m. Knurled Dork

If the throttle plate is upstream of the supercharger, you don't NEED a bypass. It's only there to eke out the absolute most fuel economy possible under non-boost conditions. Thousands of 6-71 style blown street rods work just fine with no bypass.

I think I see what you're doing, now. I saw a minivan 3l modified like you're describing, stuffed into a Neon of all things. Milled the bolt pattern right into the top of the plenum and carved out an appropriate sized hole.

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