Todd's sure fire blower sale - Fred,

[Greg Hermann]

>>
>>
>>  I was curious, so I called Blower Drive Service when I bought a 6-71 a
>> few years ago.  They said a stock, used blower without internal damage
>> should make 12-15 PSI of boost on a 454-460 sized motor with a 1:1 drive
>> ratio, and that it would take approximately 60hp to turn the blower at
>> that time.  Reworked blowers with welded or Teflon-inserted rotors would
>> make more boost.
>>
>
>I didn't think it would build that much ( I don't know how much heat the
>stock blower would generate in the air charge) IMHO  the 12-15 psi is due to
>a lot of heat in the air. With the same boost level and a reworked blower
>you will make more power because the air charge is much cooler.

After the discussion on this about a month ago, I talked to a guy who has a
3-71 Jimmy in his crawler backhoe. Has had the motor on a dyno. The 3-71
huffer on it (with no turbo) makes about 7 or 8 psi of boost. Apparently
this is about the design boost level for these things on their stock
application.

>A number I have been told for a reworked blower with the blower turning
>6000rpm and generating 15 psi boost is 100 hp. Kind of hard on that poor old
>crank snout!

Not too far off with the number, assuming a 440 cid engine.

>I have also been told that a screw charger on a modern top fuel engine
>requires 800 hp at full boost and maximum rpm.

I think this is a BIT of an exageration

Greg