Like this one I'll be using the m112 on my 270 Dodge. It is my understanding the these blowers have a fail safe burst disk between the drive and the rotors so if you do have a BAD backfire, the disk will burst. For a small backfire the belt will slip.
I know that the M-90s came on several different cars in the eighties and nineties, but does anybody know if the drive snouts are different lengths? Or which has the longer or shorter snouts if they do? I have been thinking of adding one of these to one of my Falcon sixes, and the length would make life much easier.
There is no burst area between the drive and rotors on the two M90s I have. My two are both from T-birds but the casings differ on top, one (the one I didn't use) has a raised area at the top rear and corresponding porting inside to improve efficiency. The two snouts are the same length, and you have some leeway to play with depending on what you use for a pulley. No idea on the GM M90 details. I did a brief video the other day with my old camera. Still not beating on it hard but it's working fine so far. http://youtu.be/VlR3p4TP9Es
This might help... I have a M-90 on my GM 3.8L V-6 (donor was 2000 Grand Prix) as did many late model GM and Ford products. We had to fab a 180 intake off the back of the blower to get the throttle body and air filter under the hood / scoop. It wasn't the best solution, but the best one for the truck. In the process of the build, a few Aussie guys piped to mention that some Holden engines also used that blower and some of those had different intakes than the US cars. Regardless, these engines had a wide variety of intakes and possibly snouts, but you'd have to do a lot of research to track them down. While my Eaton is stock and therefore not so HAMB friendly, since it came from a donor car it had all the right plumbing, pop-offs, and tricky gizmos to make it street friendly. It's stock, the 3.8L is flat head sized at about 230 CI, and it makes 200hp at the rear wheels. It might be worth taking a look at some GM / Holden manuals to see if there is anything you can use on your rig - my blower works great, no blips, drips or runs. Gary
Here's a 2004 GM. The TB end of the GM blowers can be problematic on RWD application. In this pic I assure you that the tape is even with the pulley & The snout splits from the case at 9". I'm not positive but there's a high probability that this mating end of the m90s would be the same, possibly the rotors too? A crafty fellow could easily fab a offset center pulley to move that were he needed an inch or two. There aftermarket modular pulley mounts, that takes care of the snout splines, and all you'd have to do is fab the pulley that simply bolted to that mount. Probably could make spacers for the case/drive surface too.
I spent most of last weekend trying to figure out how to do this to a 283. Didn't think of machining a carb mount in the front of the blower like that! Brilliant. I was thinking about making a 180 degree elbow to mate to a weber side draft. Wasn't sure the single weber would be enough of a carb. Really neat solution
Thanks! Still working great, still have generator pulley on there.. I got a couple of new flatty blocks, going to build a new engine and clean up many details when this one dies but for now it's hanging in there. I considered side draft Webbers or SUs, not a bad idea and much easier but not really right for my heap. Would look great on the right build.
Cool, good to know it worked out well for you .Yeah, tricky finding a period looking set up that won't cost the earth. I like the idea of the Thunderbird M90, should be a few of those in a yard near me. M90 to SBC 4 barrel carb with an adapter plate should be fairly straight forward to knock up on the mill. The base blot pattern of the M90 and a 4 barrel carb work quite well as there is plenty of room if you make the plate captive to the blower. Would need to fab a bracket to use the two large through bolt holes on the back of the blower so the thing isn't just held on with the 4 1/4 bolts in the carb manifold. Think I'll pinch your idea for the generator pulley too. I'm not looking for massive amounts of boost, just a bit more get up and go ( and who doesn't want a blower ?) so I think one belt will probably work for me.
I'm not using those two through bolt holes, yet, but I am using the one in front to keep the belt from pulling down on the snout. Also I think someone else on this thread mentioned a larger Eaton M1xx that might work better on a 283, my engine is a whopping 136 ci.. And I only spin to 4K, you're probably going higher and might need more belt grip.
An Eaton M112 would be cool, bit less common I think. I had a read through the Eaton web site, looks like the M90 was designed to run on 3.8 to 5ltr engines so it isn't outside of its specs to run on a 283. Not expecting huge performance improvement (the rest of the drive line would grenade!) Double V pulley might be a simple way of running what ever I find as a supercharger. More thought required I think. Oh, are you running both your carbs as primaries? Thanks for the fed back
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