Inliners International Forums General Discussion Hi Performance superchargers

Does anyone uses Vortech, Paxton, Powerdyne or any other supercharger in tha 250?
If so, can post some pics and specs about it.
I'm bending on this directions now and want to know more about it.

Thanx

I used a Paxton supercharger.
I have some pics somewhere???
I still have the Paxton & brackets,but it is an older SN 89 model.

It put out 9 psi on my engine, but I had a fairly big cam,thus reducing boost,plus ported head w/bigger valves.
Even with only that amount of boost pressure it ran mid to high 12's.

On a stock Chevy 250,you could get easy 15+ lbs of boost pressure.

You just need to make brackets on the right side of the engine attached to the cylinder head for any of the newer type blowers.

You can use the Paxton Novi 1000 or 2000, high boost.
Or a Vortech high boost model.
It is much easier to adapt a supercharger than a turbo.

MBHD

Thanks Hank

That kind of information i was looking for.

And what about the oil the Paxton uses? Is it true it cannot be shipped outside the US?

Why have you changed to a turbo? Didn't like the results?

For the older Paxton units,you do not need to use their oil.
I believe ATF fluid is fine.
With the Paxtatrac (SP)fluid they said you could get an extra pound of boost pressure.
Now this type of oil is for the older planitary ball drive superchargers,the new ones are direct gear driven.

I do not know about not being able to ship that oil outside of US.

I believe all the new Paxton Novi's use an engine oil pressure (uses engine oil)line then a return line to the oil pan? Just like the Vortecs.

If Paxton had the newer gear griven Novi units I might still be using it, because they would have been able to give me the 20+ pounds (psi) of boost pressure I really wanted.

I know a turbo can easily give me the boost pressure I want,plus I do not need to run a drive belt.

MBHD

Yeah Hank you don't need a drive belt in a turbo, which reduces drag force. But what about the response of the supercharger in low end speeds? I mean, wouldn't the blowers be better to short drag races like in 1/8 mile as you don't need to wait for them to fill the turbine?

Are there to many Paxton or Vortech different sizes? Which is better for the 250 Chevy?

Centrifugal (SP) are not good low end response, unless you have a high stall torque converter.

Roots type or screw type superchargers will give you great low end response, but usually you need to cut a hole in your hood for clearance,unless you mount it off to the side.

My Paxton really did not start pulling good untill 3500 RPM.

Same goes for a turbo, if you pick a good size turbo, you will not get boost untill you have enough exhaust flow to spool up the turbo.
Run too small of a turbine section ,then you choke off too much exhaust flow & kill top end power.
All things being equal,like properly matched torque converters etc, I tend to believe you can make more power w/a turbo.
At one time , when they allowed top fuel turbocharged dragsters, they were penilized (sp)by having to add extra weight to be far for the supercharged dragsters.
Ultimately ,the turbocharged top fuel dragsters were banned.

MBHD

There may be an exception to the low end response -

http://www.rotrex.com/

- is suppose to have better low end response,and be more efficient tha other centrifugal blowers. It uses plantentary gears and runs the blower at some multiple of the engine RPMs. It also has some draw backs, limited on displacement (250 is on the upper limit),and limited on boost. I ran across an article on this blower some time back and it looked interesting till I found were it wouldn't work on my 292.

Larry

[QUOTE]Originally posted by Mean buzzen half dozen A.K.A. Hank:
.

"Roots type or screw type superchargers will give you great low end response."

MBHD

Understood, I edited for clarification.

One of the other limiting factors is the drive belt. I read an article about centrifugal blowers from one of the magazines that said the V-belt limited them to 10-12 pounds boost. Certainly a cog belt would improve on the 10-12. Does anyone have any additional information? Serpentine limit?

Larry

Yes,
I ran a 6 rib serpentine belt,w/no slippage problems,but I was only getting 8-9 lbs of boost pressure.

B&M has been selling 10 rib serpentine belts & pulley systems, but those slip also.

My friends 10 rib setup slipped on his SBC w/a B&M (roots type) 162 blower putting out 10 lbs of boost pressure.
It depends on what supercharger you have as to how much slippage @ what psi of boost pressure.

Somewhere approx between 12 - 16,18ish psi is tops on a 8 or 10 rib serpentine set-up for a centrifugal type blower..

The gilmer (SP) cog belt drives are the best.
They also cost the most.

MBHD

And what about this:

http://www.electricsupercharger.com/
or
http://www.electricchargers.com/

Does someone knows something about this 'miraculous' things?
I'm not sure if they do really work as stated in their websites, but I don't know anyone who has tried this quite new things.
Anyone?

The second website provided little or no technical information, so who knows what it would do. It also calls a compressor a turbine.

The first website claims that its basic unit can deliver 800 CFM, 1 psi boost, and from a 1.2 HP electric motor. Note that they did not claim that you could get 800 cfm and the 1 psi boost at the same time. A quick calculation shows that 1.2 HP could boost 800 cfm by about 0.35 psi. Or it could boost about 275 cfm by 1 psi. The actual combination of cfm and boost would depend on the RPM and size of the engine downstream of the device. A good 250 at 6000 rpm would want well over 400 cfm, so the boost would be around 0.6 psi.

How long will a battery deliver 1.2 HP?

You hook them up only for full throttle.
They draw crazy amperage.60-80 amps each,IIRC.
They also tie two together to get more CFM.
You might see some small gains on a small 4 cylinder engine.

MBHD