turbo/supercharging

[Johnny]

Steve Baldwin wrote:

> My EFI target (after I finish a couple of other garage ornaments) is a
> blown, injected flathead. 

You are talking to the king of garage ornaments...

> I have the motor (rebuilt) and the blower all
> setup but with the asthmatic nature of the ports and the fact that the
> blower is about 2/3 the length of the motor, distribution is a bit of a
> problem. I'd like to port inject it, rather than try baffles to even it
> up but I wondered if running the blower dry was going to cause more
> problems, both with the extra expansion and intake heating.
> Any comments ?

They are intended to run dry. They aren't made to be draw through
induction blowers for auto engines. Most places that set blowers up,
reduce the what-should-be-on-a-diesel clearances, to something that
leaks less with the assurance that they will have fuel running through
them to keep them below a certain temp. When used dry, they need there
regular clearances that they would have had on the diesel (or maybe a
little tighter), but they can still benefit from the teflon scrapers,
modified rotors, and smothing tricks that are done (none of this applies
to other than GMC's though... I've never run any of the mickey mouse
ones, so I am clueless on those). They won't get any hotter than the
rest of the engine, even with air compression, because they still have
relatively cool air going through them. Or let's say you would have to
be running some serious boost, and for prolonged periods, to get the
average air temp inside the housing to over 250 degrees (the temp of the
rest of the metal on the engine). The intake charge is still cooled by
the fuel injection, just after the blower instead of before. And it
still vaporizes like crazy because you are shooting cold fuel into hot
air. You also don't have to worry about what is going on with the fuel
particulate in that awful intake manifold or loading up the blower
housing sitting at an idle. Not to mention that highly eventful
unscheduled backfire.

For much more experience than I have with blowers, I would recomend
giving Hampton Blowers a call at:
909-613-1426
I haven't talked to him in a year or two, so I don't know how current
the number is. About all he does is blowers and everything having to do
with them. If anyone is doing something with blowers an efi, he'll know
about it.

BTW, you can get just the housing and butterfly part of the 3 hole from
Hilborn for only a couple hundred more bucks than a new Accel or
Electromotive airdoor will cost you. Out flows it about 3:1 too.  ;O

> These things love to be blown. Every thing happens where a modern Jap
> car considers to be a fast idle and a bit of puff just adds more low end
> torque. Not much upsets a SBC owner more than being shut down by
> something 60 years old and sounds like a tractor going through the
> traps.   :-)
> 

a really pissed off tractor...  ;)

-j-