Running a centrifugal supercharger backwards

[TonyL]

I've devised a plan.

corvairs like mine have limited options when it comes to aftermarket induction options. there's this thing.

https://static1.pt-content.com/images/noimg.gif

It makes it so you can convert the 4 little one barrels, which are hard to sinc up to a nice 4150 type holley carb.

Neat, but still, a carb. still difficult to get to work well.

But then I saw this puppy,

https://static1.pt-content.com/images/pt/2009/04/30226kit_600-1.jpg

And I think it'll work awesome.... Especially with a supercharger hooked up to it. My car cant see loads of boost, but that's not the biggest hurdle.

My engine rotates BACKWARDS. all corvairs do. Can one modify a blower to run backward? I know it can be done with a roots type one. But this? Anyone? Bueller?

[Twentyover]

You can weld injector bungs tothe tubes adjacent to the port, to make this MPFI, rather than a TBI, and use a regular throttle body.

As far as the supercharger, can you devise a gear driven jackshaft to reverse rotation (maybe something like the cam drive gears on the Ford 2.8) Centifugals won't work backwards.Maybe a turbo may be a better bet?

[TonyL]

possibly. I've thought of running a pulley under and another one just over the top and "S"ing the belt. running the belt up against it, rather than around it, I'll have to model it.

I do have a turbo already though.... an older one, but still. Free is good. Turbo Corvairs have been done though, I want to be different.

[TonyL]

MSPaint FTW!

Will this work? Or does the belt need better contact than that?

https://static1.pt-content.com/images/noimg.gif

[parsonsj]

Tony,

I've done some fab with supercharger pulleys (a loooong time ago), and we had a hell of a time with belt slippage. And we had almost 150* of belt contact. The 70* in your drawing just won't cut it. I think you need to try and get 180*, if possible.

jp

[TonyL]

i thought so. thanks!

[CarlC]

Agree with John. Mine has more than 180* and is very close to slipping.

[RSX302]

I agree with the weld in injector bungs at the head. When you get that far out, it's ugly for tuning/response. Much nicer at the head if you can get it there.

My Kenne Bell blower had a little more then 180* on the pulley with a 5 spline belt. It was only 8psig boost. Street blowers pull around 30-50hp and race versions around 100hp. God knows what a Top Fueler does....Probably the amount my Twin Turbo V8 does..:rotfl:

[camcojb]

Procharger makes reverse-rotation centrifugals, I had one on a Cobra replica where turning the blower backwards was the only way it would fit.

Jody

[Roadbuster]

Tony,

How about mounting the supercharger the other way around?
Mount it facing toward the back of the engine (the front of the car) instead of toward the front of the engine (back of the car). This way You don't have to change any internals or buy a custom rotating assembly and just have to fab the custom mounts which you would probably have to do anyway. The rotation is reversed and you can still get a simple pulley arrangement. The pain would be in changing the belt.

Jon

[Nessumsar]

Why not mount the super charger not on the engine, spun 180*?

Make a mount that bolts to the engine but extends out far enough to mount the charger bolted in backwards?

Like on Notorious?

[TonyL]

Sometimes the simplest solutions are the hardest ones to see. I cant believe I didn't think of just mounting the compressor itself backward! *d'oh*

[RSX302]

But then I saw this puppy,

https://static1.pt-content.com/images/pt/2009/04/30226kit_600-1.jpg

And I think it'll work awesome.... Especially with a supercharger hooked up to it. My car cant see loads of boost, but that's not the biggest hurdle.

Check to see if they will run different MAP sensors for boost. In the instruction manual it says it comes with a 0-105kpa sensor.

[TonyL]

will do.

I've also thought about welding bungs into the manifold and just finding a throttle body that'd work. The problem is thanks to my engine's bizzare layout, firing order, reverse rotation, etc there isnt a management program in the world for it.

In the corvair world theres a HUGE demand for this type of setup. getting all 4 carbs to work is really difficult for most. I can't believe someone hasnt made a kit for us weirdos yet. They'd sell like hotcakes.

[gkring]

will do.

I've also thought about welding bungs into the manifold and just finding a throttle body that'd work. The problem is thanks to my engine's bizzare layout, firing order, reverse rotation, etc there isnt a management program in the world for it.

In the corvair world theres a HUGE demand for this type of setup. getting all 4 carbs to work is really difficult for most. I can't believe someone hasnt made a kit for us weirdos yet. They'd sell like hotcakes.


I have done a few cars using a system designed for one motor, then used on another. As long as you know the firing order the ECM is using you can just run the wires accordingly. if you are using a distributor it is real easy since you just have to run the injector wires correctly. All of the systems I have seen that are not made specifically for one car can have the firing order changed. The distributor signals are the same, it does not matter which way the motor turns. An ECm programmed to give 10 degrees advance won't give your motor 10 degrees of retard just because your motor spins the opposite direction.

[Damn True]

Centrifugal run backwards? That would suck.

[6'9"Witha69]

Centrifugal run backwards? That would suck.
:lol:

[TonyL]

lol!

The weirdness that is the corvair is thus: 4 intake ports, two per head. *six cylinders* per head. Weird compression waves sharing the plenum inside the manifold/head. would most likely be a problem. Now, there's a mod out there that mills off the head, and lets you bolt on *six* runners so I'd have one injector per runner. solving that problem. But it's exorbitantly expensive.

Hence me going for the simplest carb-like answer.

[gkring]

That makes more sense. Looks like you need to stick to a throttle body injected style system. If you keep the ignition seperate (I would NOT) it would be very easy as you just need a tach signal to fire off the injectors in batch mode. it would basically be a carb, but with better control and O2 sensor feedback capability. The ignition control is a really nice gain for a supercharged application like you are planning.

[mjoc1]

The six carb intakes are not that expensive. I have seen them for $400.00 Do you belong to the CORSA.
Mike

[TonyL]

i do not belong to corsa. Perhaps when they get around to entering the information age, I'll think about it. That they charge for membership bothers me. They should have a messageboard and free membership.

For the price they charge the communique isn't enough for me.

[Lance-W]

lol!

The weirdness that is the corvair is thus: 4 intake ports, two per head. *six cylinders* per head. Weird compression waves sharing the plenum inside the manifold/head. would most likely be a problem. Now, there's a mod out there that mills off the head, and lets you bolt on *six* runners so I'd have one injector per runner. solving that problem. But it's exorbitantly expensive.

Hence me going for the simplest carb-like answer.

That's called a Trioka manifold. They were around back in the day. You still see the heads that we're modified for it every so often.

On another not I ran a center Holley 390 cfm carb 4 barrel with the Edelbrock (if I remember right) 4 tube intake manifold and it was a huge improvement over the 4 one barrels.

[mjoc1]

I don't belong to Corsa but if you join your local corvair club they will let you use the corsa resources. Alot of the guys there have alot of wierd stuff for the corvair motor.

Mike

You could also try LS Corvair parts for some good deals.

[Fuelie Fan]

If I came up with a low cost system that worked, how many buyers do you honestly think there would be? Also, what is the corvair world's price break point for "affordable"?

[TonyL]

Us corvair guys are notoriously cheap. Is there a market? Bigger than you'd think. I'd say several hundred guys might be interested for sure. It's been a pipe dream for SO long. Clark's Corvair was working with someone a long time ago, and had several pre-orders. Corvairs are hugely raced, autocrossed and are gaining popularity every day. I get emails almost weekly from someone who found my car on the net, and ran out and bought one. I'm thinking a movement is starting. Cheap cars, easy to build, and surprisingly good handling.

The price break? 1000 bucks. much more than that, and you'll never sell them to "corvair guys". Do it for 800 bucks, and you'll sell hundreds of them right away. There's a blossoming market for "hard core" pro-touring corvair guys. Guys who couldnt care less about the classic image of a restored corvair, and just want the fun, cheap platform to build on.

Hence me starting my own website. www.hardcorevair.com.

[Rhino]

Hence me starting my own website. www.hardcorevair.com (http://www.hardcorevair.com).

I love the play on words. Great URL choice! :twothumbs

[6'9"Witha69]

There's a blossoming market for "hard core" pro-touring corvair guys. Guys who couldnt care less about the classic image of a restored corvair, and just want the fun, cheap platform to build on.

Hence me starting my own website. www.hardcorevair.com (http://www.hardcorevair.com).
I've been thinking the same thing about '69 Camaros. Think it'll work?





j/k





I've seen several showing up and swapping hands @ Pomona and other places recently. I think a LOT of people are geetting into these little cars.

[DJW32]

The price break? 1000 bucks. much more than that, and you'll never sell them to "corvair guys". Do it for 800 bucks, and you'll sell hundreds of them right away. There's a blossoming market for "hard core" pro-touring corvair guys. Guys who couldnt care less about the classic image of a restored corvair, and just want the fun, cheap platform to build on.

Hence me starting my own website. www.hardcorevair.com. (http://www.hardcorevair.com.)

Tony,
That price point is not realistic. The supercharger will cost more than $800. Keep up the good work.

I think your paint job is sweeeet!

[fast Ed]

There are reverse rotation centrifugal blowers available, most of the stuff for the Ford mod 4.6 engines are set up that way.

The new FAST system is not designed for boosted applications, from the latest info I saw on teh intraweb.


cheers
Ed N.

[mjoc1]

I would be interested. I own a corvair van and I am in the process of actually trying to sup it up on the cheap.

Mike

[TonyL]

Tony,
That price point is not realistic. The supercharger will cost more than $800. Keep up the good work.

I think your paint job is sweeeet!

was talking only about the fuel injection idea. Not a supercharger also.
Im not sure what'd it be. But yeah, well into the 2 grand area for a setup.

The stock carb/turbo setup usually costs about 1800 bucks complete if you want to convert a car. Sometimes less. Depends. But the output is only bumped from 140hp to 180 hp. Not a huge improvement. But with todays fuel systems, computer controls and stuff, one should be able to wring out lots more power.

[DeltaT]

Many of the Vortech models are available in clockwise and CCW, so you have a lot of choices. For EFI, check out the Holley Commander Pro w/wideband sensor. It's available with a universal wiring harness and all sensors for around $1000. All you need is an EFI-ready fuel setup and a distributor that puts out a firing signal (any MSD inductive trigger works great) and a throttle body with TPS and an IAC. Not a tough project nowadays.

Jim

[Fuelie Fan]

$800...you guys are tough! Is that supposed to include injectors, sensors, throttle body(ies)?

[JMarsa]

I think GM TBI stuff and a Megasquirt set-up on a custom fab'd intake could be put together with a profit for $800-1000.

--JMarsa

[fantasygoat]

I was going to recommend Megasquirt. They've got it working perfectly on far more esoteric platforms than Corvairs!

[Fuelie Fan]

It's one thing to get it to work. It's another thing to allow enough "profit" to pay for all the product support that goes along with fuel injection systems. $800 is extremely tight. I don't think I'd mess with it, personally.

[fantasygoat]

If you're a DIY kind of person, you can assemble a Megasquirt injection system for $500 or less out of a combination of OEM and aftermarket parts.