rebuilding supercharger

ITSAV6

Registered User
I can buy one that cant be turned by hand for $50. What would it cost to rebuild it? We are gonna use it to boost a 4.6 Cougar. Got the idea from this web site Twin Supercharged Turbo Coupe
We are gonna try it with one on the 4.6 V8 and hoping for 8-10# of boost. Will it be able too make that much boost on the 4.6? Thanks Guys!
 
Yeah, if the rotors can't be turned, you myswell start with a new blower. The only things that can be reasonably rebuilt are the snout seals, bearings, and shaft. IMO anyway.

Thomas
 
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rotors

The rotors dont appear to be damaged. We are going to fabricate brackets,inlet/ outlet tubes and mount it on pass side of eng. Inlet tube will run to maf and outlet to throttle body.
 
the throttle body must be on intake side of sc

dont presurize the tb itll send pressure into iac it must be mounted on intake side of blower
 
t-body

Almost all aftermarket S/C pressurize the t-body and the Grand National does too. I know what your saying but we will probably use a bypass to bleed the pressure off when the throttle closes.
 
Try this....

When you look at the blower, see if you can disconnect the shout from the rotor case.

Now see if you can turn the snout drive by hand, and see if you can turn the gears for the rotors by hand. If you cannot turn the gears on the rotors then don't buy that Supercharger.

Also see if you can get a supercharger from a 94-95 supercoupe. Their rotors are powder coated and therefore have tighter clearances, therefore more efficient operation. You'll get more HP out of it.
 
Ya, the 94-5 blower will give you some more ponies till the powdercoated rotors (they are NOT teflon coated Ughhh) starts peeling. I wonder if anyone has ever dynoed the early style blower against a late style one without making ANY other changes?
 
How come powdercoating peels?

Powdercoating (done properly) is some pretty tough stuff, why does it start to peel off on some of the 94-95 superchargers? Heat? Chemicals? Quality1?
 
blower rebuild

Hi All!
Has anyone here actually successfully rebuilt the blower? I bought my sister's '90 sight unseen when she intended to trade it (for peanuts) in on a new car. I flew to NY. Started it up, and the supercharger was rattling like hell. Im like, "Thanks for telling me it was making a godawful noise..." Checked the oil in the case. There was no oil in the case. Just burnt muck. I had no way of getting "supercharger oil", and it was trashed anyway, so I filled it with 90w synthetic gear lube. It is a gear, after all.. And then I drove it to Florida like that, heel toeing to keep it off low idle, where the rattling was worst. Made it, no problems. Anyway, pressed it apart after finding no rebuild parts sources. Bearings are fairly standard. The rear ones are the same as a common Ford pilot bushing size. Couldn't get seals. Magnuson (rebuilder)said they don't replace them. Bull. That's the most common problem! Leaks. So I had some made. Cost a fortune (for seals!) I think it was $130 for two of each. They fit. looked good. I put it together and it sounded decent. Obviously, the gears were a bit noisy since they had..ahem, "clearanced" themselves somewhat during their unoiled life. It ran good. It ate oil. It began to get aluminum in the oil. I took the belt off and drove the car for 6 months like that. (Talk about NO power!) Found a used one and put it in. Old one's on the shelf....Rebuilds...who has done it??! Not I said Scott! Cheers!
 
Plenty of people have rebuilt the blower nose drive that is usually the problem. The proper oil can be bought at a GM stealership. Tell them you need SC fluid for a Regal GS or any of the other supercharged cars. One common cause for the rattle is the spring in the coupler can break and you will have about 15 degrees of slop when you turn the pulley. The older cars 89 and some early 90’s have a solid coupler that is a little noisier than the later spring coupling, but there is no performance advantage one over the other, the spring is just there to absorb some of the changes in load. Like when you are idling or cruising, there is little load on the rotors when the bypass is open and the coupling clicks and clacks. When you get up on it there is a constant load on them and the drive pins are forced against the stop. You can pick up used blowers very easy and cheap I have paid between $60-150, and the 150 was a late model with a bad snout.

The seal is manufactured by Chicago Rawhide.
# 7968 (preferred) #7965 or #7966 can also be used.
Run between 20.54 – 2.42 Applied Industrial Tech.

The bearings are made by NSK. You will need one of each.
# NC6204C3X28
# NC6203C3X28

Loctite sealant
# 51831 Gasket Eliminator 518, 510, or 504 Found at Grainger

Grease:
Husky pt # 00603



The coating on the rotors is an epoxy though no one is sure exactly what kind. It's not powder coat, but that might not be a bad thing to try, it is not any kind of PTFE (Teflon). I have an industrial paint that is called Epoxy Polyamide and it's made by PPG. I have painted the chromed plastic grill and chrome bumper without so much as roughing it up and it has been on there for 5 years (and I don't wash cars), and survived a collision with a Toyota truck only to have chrome from his bumper end up on my bumper, didn't even scratch the paint.


Jeff
 
Thanks Jeff

Hi Jeff!
All this stuff was done before I found this place. What a pity.. There may be hope for the old 'charger yet. I think the aluminum was coming from the rear snout bearing. It was a bit loose going in, even with the loctite. The case was worn there where the old bearing had gotten hot and spun. With cheap replacements to be had, I doubt I'll rebuild it except as a last resort. I'm saving this info for future use just in case! Thanks again, Scott P.S. Neither of my blowers has any coating.
 
Actually the locktite is a gasket eliminator. It is for sealing the blower snout to the case, the blower top to the case and the blower inlet to the blower case. If the bearing is that loose and the case is galled, then you will have to have a machine shop bore, slip a bushing in and re bore it to the correct dim.

Jeff
 
Originally posted by ITSAV6
I can buy one that cant be turned by hand for $50. What would it cost to rebuild it? We are gonna use it to boost a 4.6 Cougar. Got the idea from this web site Twin Supercharged Turbo Coupe
We are gonna try it with one on the 4.6 V8 and hoping for 8-10# of boost. Will it be able too make that much boost on the 4.6? Thanks Guys!

Unless you are starting with a 24-valve 4.6 for a base engine, then go ahead and make a trip to the local garbage dump for an empty 55-gallon drum or two...you'll need 'em to throw broken 4.6 parts into. If you made a typo & meant to say 5.0, then all is well. :)

'bird

ps: dreamt about having an Aston Martin Vantage last night...
 
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hee-hee

:D It aint my 4.sh**,I mean 4.6 LOL. It's my buddies car. We are already spraying 100 horse N20 on it and wanna try something different. If it goes boom were gonns build a DSS Bullet short block w/low compression pistons and good rods etc.:D
 

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here kittykitty...

Originally posted by ITSAV6
:D It aint my 4.sh**,I mean 4.6 LOL. It's my buddies car. We are already spraying 100 horse N20 on it and wanna try something different. If it goes boom were gonns build a DSS Bullet short block w/low compression pistons and good rods etc.:D

Okay, gotta get my daily dose of 4.6 harrassment done.

here kittykitty...

burn816.jpg
 
Allen Enginering makes a supercharger kit that uses a S model M90 for the 4.6 FYI

Jeff
 
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