Roots style supercharger question.

[Brad]

Is anyone running a 6 or 871 supercharger on their big block? I was wondering which is better for a street/strip car, teflon stripped or not? Any feedback will be appreciated.

[Challenger340]

Pro's and Cons both ways.
I don't bother with strips for street applications, my experience has been they just fall off.

Either way, it's a real good idea to have a second keyway cut in the crank snout, 180 degrees opposite from the stock keyway.
Make it a 1/4", and you'll also have to get a matching receiver groove broached in the Balancer to match.

Just keeps stuff "where it 'outa be".

I'm doing one for a guy now, you want a photo for a guide ?
It's a SB Chebby W/671, but same deal.

Bob out.

[Blown70]

K well I am a fan of strips.  But I do see the down side to them too.

I would run and 8 over a 6.  But if you can get a deal on a 6 dont pass it up.  with inlet air temps, the less you have to rotate the supercharger IMO and many others the better.

Tom

[Brad]

Thanks for the replies. It would be nice to have a picture, but I think I know what your talking about Bob. Hey blown 70, How long have you been running a blower? What kind of engine specs are you running? If you don't mind me asking?

[Blown70]

Thanks for the replies. It would be nice to have a picture, but I think I know what your talking about Bob. Hey blown 70, How long have you been running a blower? What kind of engine specs are you running? If you don't mind me asking?

Ohhh that is not my motor in the pic.  I am happy to entertain conversation, but keep in mind just like anything some peoples opinions are different when it comes to them.....  I can show you a pic  of a degree ring with the keyways cut I would have to take the pic.

Lmk
Tom

[Brad]

Thanks Tom for the info. I'm getting ready to start a new engine build and I'm thinking of going with a supercharger. Just trying to get more info. The new build will at least be a 500 stroker with aluminum heads. The engine in the car now is unknown as far as specs. It runs decent but is not as fast as my old engine. The car was at my fathers house and it got vandalized. He had a local shop build this engine and they went out of business and didn't give him any specs or the dyno sheet that they promised. The car ran 11.50's with the old engine. Now I need more power. I haven't run the car with this engine but I would guess it in the twelves by the seat of my pants feel.

[Mike DC]

If you've never read into the screw-type superchargers, you might want to.  (Newer blowers, they look kinda like a smaller version of a Roots-type but they don't work the same way.)


The top end power numbers are lower than a Roots-type, but the streetable midrange torque on the screw-type is monstrous.  These things basically dump a steadier amount of boost into the motor at a wider range of RPMs. 

[Runner]

dont the thunderbird supercoupes and ford lightnings all use screw type blowers? as well as the mid 90s grandprix's?

[Brad]

Are you talking about a PSI blower? What companies sell the screw type?

[472 R/T SE]

     A little OT, but do you know where the motor in my old R/T came from Brad?  Logsdon told me it was #'s matching but when I checked it, it came out of a '69 Charger R/T.  Full VIN's were stamped on '69's so I just got to wondering since you're swapping motors.  Fat chance, but I hope it didn't come out of your car.
     It sounds like you're building a monster. 

[Brad]

My original engine was long gone when I bought the car. I don't remember where Dave's engine was from, but who knows. If I ever found the original engine I don't know what I'd do. Restoration would be the smart money, but I am more of a modified guy. Got to have the speed!!!!!!

[Blown70]

My original engine was long gone when I bought the car. I don't remember where Dave's engine was from, but who knows. If I ever found the original engine I don't know what I'd do. Restoration would be the smart money, but I am more of a modified guy. Got to have the speed!!!!!!

HEHEHEHE I like this kind of thinking......

[ronv]

Here is a picture of the blower I have in my car. Well its not in the car any more. After getting this far I spoke with some people who I respect and also got great advise on this site and ended up removing the engine. I have the crank at a machine shop putting in another key and I also purchased a main girdle kit. I suggest speaking to JR at RBS Superchargers. He knows blowers and is real cool to deal with. Plus now with the engine out I can install the Unisteer rack and pinion steering I talked my wife into letting me get.

[Blown70]

Here is a picture of the blower I have in my car. Well its not in the car any more. After getting this far I spoke with some people who I respect and also got great advise on this site and ended up removing the engine. I have the crank at a machine shop putting in another key and I also purchased a main girdle kit. I suggest speaking to JR at RBS Superchargers. He knows blowers and is real cool to deal with. Plus now with the engine out I can install the Unisteer rack and pinion steering I talked my wife into letting me get.

RBS is great to talk to!!!  I have spoken to 2 different TECH guys.....   Other than Littlefield, who is also good to speak to, I would not deal with almost anyone else!!!!  Mert Littlefield is very knowlegable worth the phone bill!!!!

RBS

http://www.rbssuperchargers.com/

[Brad]

Thanks for the advice and the link. I love the picture of your engine ronv.