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Re: Supercharging little hemis? ? HELP!

To: ARDUNDOUG@aol.com
Subject: Re: Supercharging little hemis? ? HELP!
From: Dave Dahlgren <ddahlgren@snet.net>
Date: Sat, 03 Feb 2001 07:03:07 -0500
If you are going to use a non Roots style blower consider 2
things both good actually. First the roots style has the
worst of compressor efficiency of all. That means it takes
more power to drive per pound of boost and makes more heat
in the intake charge per pound of boost.  if you run a belt
driven unit I personally think the Vortech is the best. It
is reasonably small has a lot of different compressors
available and very reliable, It still takes power to run
though. It has boost that is proportional to rpm which is
good in many respects.  If you run a turbo it uses the least
power to run and makes boost according to LOAD. A real
important feature. This can be adjusted according to exhaust
housing size and costs little more than the pulleys you
would use on the belt driven stuff. The turbos really take
up the least amount of room also as the are exhaust mounted
so you have some choices as to where to mount them and do
not have to line up any belts etc..  With the being load
related in boost they are more drivable than any belt driven
piece also. No load no boost that simple. So they are not
such an instant on thing. If you are at B'ville this might
be good, at Maxton maybe not or maybe no problem. It all
comes down to how much boost you want also.
Dave Dahlgren
ARDUNDOUG@aol.com wrote:
> 
> In a message dated 02/01/2001 7:51:06 AM Pacific Standard Time,
> lsr_man@yahoo.com writes:
> 
> << I need to keep economics in mind, so I don't want
>  to buy expensive stuff that will only be used on
>  the stepping stone.  For the roadster, I will use
>  a 241 Dodge hemi.  I talked a lot with Dan
>  Hostetter, who really knows lil Dodge hemis, and
>  he says that the Dodge will not flow more than
>  about 450 CFM cause everything is so small.  I
>  want to use a supercharger on the Dodge.  I'm
>  thinking about a centrifugal supercharger
>  (Paxton) and a good two barrel carb.  With the
>  Dodge's stock 7.5 CR, it ought to make a neat
>  little motor.
> ############################
> Dick,
>     I'm as new as you are regards blowers. Our little Ardun is only 258ci,
> running the 4:71 at 16% over on alky. The static compression ratio is 8:1.
> Induction is a "2-holer" Hilborn on a homemade intake with nozzles in both
> the "hat" and individual ports. The boost gauge shows 21lbs, somewhat higher
> than we expected.
>     So far we've only made four passes with the engine in the Dragmaster Dart
> (weight 1600lbs including driver) at Sacramento Raceway drag strip. On the
> last pass the Vertex slipped in the "pinch-ring", backfired the blower, the
> burst plate didn't, the Gilmer belt held, and the snout broke off the
> dragster, giving Son Brian a 90w gear oil bath. The snout then passed under
> the car, dinging the headers, motor plate belly pan, and frame. Despite
> scattering parts from 50' short of the lights, the timing slip showed
> 8.84/160. Brian saw 170 on the tach just before the explosion.
>     Your little Dodge has far more potential than you realize. It would love
> some serious compression (or blower boost), and a diet of alky, possibly
> spiked with a little nitro.
>     Dan Hostetter is very knowledgeable regards the Dodge Hemi. The 450cfm
> figure, however, might be a little conservative.
>     One thing for sure about little Hemi's is that they love nitro and plenty
> of compression ratio.
>     Regards the Paxton, give plenty of consideration to the manifold
> fabrication required. If you're building a custom manifold you might just as
> well make it to accept a GMC blower.
>     Regards the small 2-bbl carb, I'd cobble up some kind of fuel injector if
> it we're mine..................Ardun Doug King
> 
> If I use a jimmie, I'll have to
>  have a custom intake made, and it will stick way
>  up out of the roadster's hood.  The Paxton will
>  be a lot cheaper, will huff the Dodge to it's max
>  anyway, and will all fit under the hood.
> 
>  If I go ahead and get the Paxton now and use it
>  on the stepping stone Camaro, do you think that
>  the Paxton will raise the SBC current estimated
>  output of 400HP to 500HP?  I know that Dart heads
>  and some nitrous would easily do that, but I
>  would rather spend my money on parts that I'm
>  going to keep.
> 
>  I'd like to see 200 MPH one time at Bonneville
>  before I go to the big track in the sky, and I
>  figure the Camaro is the most likely candidate to
>  get me there, and a tic over 500 HP should be
>  what it takes.
>  Will the blower get me there?
> 
>  Comments, ANYBODY ? ?

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