Is there any company that has, does or will be in the future manufacturing a direct driven supercharger? What I mean by this is that supercharger is directly bolted to the crank connected via a shaft or gear unit.

I have heard of this and have seen it at the local drag strip a few years ago. I was not able to visually examine the car that was that was running this setup. But it seems to me that you would be able to get better efficiency out of the supercharger. Also it should prolong the life of the supercharger because there would be no “pull” or down force caused by the belt, thus not causing premature bearing failure in the head unit.

I’m trying to find out what are the pros and cons of a setup like this. So if anyone has seen, has pictures, or knows of a company that manufactures an assembly like this let me know.

 

Well a cogged set up would be considered direct. I think some people had belt problems/failure with coggs on the street. It would normally be done for race setups that require alot of horsepower to turn the blower.

You could drive a charger with a motorcycle chain and sprokets..never seen that before.

Old, old, positive displacement blowers were sometimes driven right off of the crank I believe.


This is true to an extent but not really an issue. I have heard of some breaking crank snouts off due to belt tension.

Hope this helped

-Scott.

 

There was a company some years ago that made exactly what you're talking about. It was basically a modified turbo prop supercharger that was directly bolted to the crank. The problem with that setup is clearance since it was bolted to the front of the engine, it would add another 2 feet to the motor. I remember Hot Rod had an article on an old like 1932 (I think) coupe that was built with one of those blowers and a 350 chevy. The front was completely reshaped and the suspension was modified to allow the blower to be mounted. Unfortunately, I don't remember the name of the company that made them.

 

What I’m talking about is basically taking a centrifugal supercharger and modifying the snout on it so that it is directly driven via gears. IE one on the end of the crank and one put in place of the regular pulley on the head unit.

Or set it up so that it uses slotted gear teeth, like a spider gear so that that it would slot onto the end of the crank. Essentially the supercharger is directly bolted onto the end of the crank.

The setup that I saw at my local track was no two foot unit. I believe it was in a fox body mustang, it retained its stock front end (at least if you looked at it, it looked stock). Basically it would be the size of the head unit plus maybe four inches

 

Being a bit more specific in the first post would have helped. A motor plate and some custom gears could easily be made to work with what you have in mind. There won't be much slack in the gears which will probably destroy the impeller after you let off the gas a few times. I thought you were referring to an older type front mount blower similar to this...
http://upload.wikimedia.org/wikipedi...t_34_right.jpg

 

http://www.thesuperchargerstore.com/geardrive.html

I got a buddy running this setup with a Procharger F2 on a SB2 motor on alcohol. Works awesome.

 

Now the point that you bring up 97WS6SCharged about there being no slack in the gears is a good point. So would this actually cause the supercharger to destroy itself or is this just a guess at what could happen? I know virtually nothing about supercharger construction.

It’s just that locally I’ve know a few guys that have had superchargers that have blown because of the “pull” or down force caused by the belt. One unit blew up with less than 3000 miles on it!! Other failures I’ve heard of are, bending the input shaft on the supercharger, seized bearings and pulleys coming off.

It seems to me that one could extend the life of the head unit if there was another bearing and bracket mounting point on the front of the pulley of the head unit of the supercharger. So two bearings would carry the “pull” or down force caused by the belt.

Hey TimbrSS what vehicle is your friend running that type of setup on? I guess from reading on that website each unit is a one off production for each vehicle. So has he had any problems with it such as there being no slack in the gears? Also how big is the whole unit? From the pictures it appears to stick out about 18-20 inches from the block. So the only way for them to fit this unit in without modifying the front end of the vehicle was to section the radiator into two pieces?

 

Well, cog systems have been known to shred the teeth off of the belts when the throttle was suddenly snapped shut. With a gear drive, there will be even less give, and I seriously doubt the gears themselves will break (depending on what they are made of).

 

Procharger is doing this with a direct drive off the crank snout. Obviously not applicable to most street cars due to packaging and not needed for 90%+ anyway.

Rich

 

Rich-

ProCharger isn't doing any kind of direct-drive. It's one of their dealers, The Supercharger Store. http://www.thesuperchargerstore.com/geardrive.html

 

That is not a problem if you have the correct surge valve on it. There are MANY cars out there running a cog system on the street. Hell, ATI's 350Z and G35 kits are cog driven.

 

So if a setup like the one produced by the supercharger store had surge valve that operated correctly, you wouldn’t have to worry about there being no slack in the gears?

This setup should be easier on the bearings and mechanical inner working of the supercharger. It should also be able to produce more power sooner, because there is no belt slippage and it is directly attached to the end of the crank.

I’m looking into putting a setup like this into a late 70’s Chevy truck, so I should have enough space in the engine bay for a setup like this. If not I’m sure a little modifying to the radiator and its supports should be able to make it fit. Right now I’m trying to decide if I should go with a BBC or go with a Gen III 6.0 iron truck block and stroke it to a 408/409. If I went with the Gen III block I would want to keep it fuel injected along with all the electronics. To me supercharged carbureted block that doesn’t have the blower sitting on top of the block looks funny. So I guess I’m kind of leaning towards the Gen III block.

 

Hmm, I thought I saw it in their dealer catalog? I'll look again.

Thanks for the link.

Rich

 

A big block vs. a small block with a centrifugal SC is a no-brainer, to me. I'd take the BB (in the context of no packaging problems) hands down. The hp to be gained from more displacement/better breathing is far more cost effective and reliable than for forced induction. We're talking thousands of dollars less expensive and FAR more reliable in this context.

Rich