DIY_EFI Digest         Thursday, July 29 1999         Volume 04 : Number 438



In this issue:

	Re: DIY_EFI Digest V4 #436
	Re: ecu7 boards
	BOUNCE diy_efi@xxx.edu:     Admin request of type /\bcancel\b/i at line 4 (fwd)
	Re: Smokey's Homogenizer
	Re: #437 Carby / supercharger
	Haltech temp sensor

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Date: Wed, 28 Jul 1999 17:29:56 EDT
From: ARoss10661@xxx.com
Subject: Re: DIY_EFI Digest V4 #436

Date: Tue, 27 Jul 1999 10:39:10 -0400
> From: Barry Tisdale <btisdale@xxx.com>
> Subject: Trip computer?
>
> I owned a Dodge Omni, early '80s carb version, which had an aftermarket
trip computer installed.  It'd give you MPG, time to empty, miles & time to
destination, etc.  Info needed by it was wheel rpm, time & fuel flow.
Flowmeter on fuel line to carb gave it that info.
>
> Question:  are there any units available for FI engines, where a fuel
flowmeter wouldn't be of much use?  Could you get *any* sort of accuracy
calculating from rpm, bpw & throttle opening?  Maybe 2 flowmeters, one on
supply rail, one on return line, subtract out from in?
>
> Any thoughts from anyone?
>

> Thanks - Barry

The "compucruise" unit (sounds like what you have) was available with a
little black box for EFI use that totalled the injector open time to
calculate fuel flow. Worked real good.
>


I have a brand new "compucruise kit" in a box.  I asked on the list about it 
and one fellow said he had the conversion kit to make it for efi,  ck the 
archives

Al

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Date: Thu, 29 Jul 1999 15:37:09 -0700
From: Al Lipper <efi@xxx.org>
Subject: Re: ecu7 boards

I've been away for several weeks, and have been trying to get a cheaper
price on the boards (it's now over $100 each).  I'll get back to my search
this week I expect.  I do have some ECU6 boards left if you want one.  They
cost $37US plus shipping.  Just let me know if you's like one and I'd be
happy to get it out to you.

				Al


At 03:58 PM 7/22/99 -0400, you wrote:
>Hi There;
> Have you got a price on the pcb's yet? if not do you still have any ecu6
>boards
>
>thanks
>--
>Pat Ford                           email: pford@xxx.com
>QNX Software Systems, Ltd.           WWW: http://www.qnx.com
>(613) 591-0931      (voice)         mail: 175 Terrence Matthews          
>(613) 591-3579      (fax)                 Kanata, Ontario, Canada K2M 1W8
>

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Date: Wed, 28 Jul 1999 15:55:56 -0700 (PDT)
From: Orin Eman <orin@xxx.com>
Subject: BOUNCE diy_efi@xxx.edu:     Admin request of type /\bcancel\b/i at line 4 (fwd)

From: "Gary Derian" <gderian@xxx.com>
To: <diy_efi@xxx.edu>
References: <199907281900.PAA31616@xxx.edu>
Subject: Re: DIY_EFI Digest V4 #437
Date: Wed, 28 Jul 1999 17:05:34 -0400
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The biggest problem with pressurizing a carb is the carb cannot compensate
for increased air density and will go way lean as boost goes up.  You can
fool it by closing way down on the air correction jets so the carb goes way
rich at high air flow but than you have two wrong things trying to cancel
each other out.  It usually doesn't work well, but it can work.  It goes
without saying that everything in the carb has to reference boost, fuel
pressure, float bowl, air jets and including the throttle shafts.  You must
seal or pressurize the throttle shafts otherwise fuel will leak out under
boost.

Carbs behave better when used as draw through but that introduces a
different set of problems.

Gary Derian <gderian@xxx.com>

>
> Hi all,
>
> With the list in digest mode it seems the mail has really slowed down.
Anyway,
> I'd appreciate if someone has a solution for this minor inconvenience.  I
have
> finally managed to get my Fiat 850, with the MR2 supercharger on it,
running.
> Currently its using the original carby in a blow through configuration
(the
> setup is crap, but will have to do for the time being).  With the whole
carby
> being pressurised there is enough fuel pressure in the electric pump to
make the
> car idle, however I'm sure as the pressure builds up the fuel pump runs
out of
> steam.  What is the solution?
>

------------------------------

Date: Wed, 28 Jul 1999 20:33:26 -0400
From: Shannen Durphey <shannen@xxx.com>
Subject: Re: Smokey's Homogenizer

Steve Buchholz wrote:
> 
> I know Smokey Yunick had a system where he put a turbocharger in front of a
> carb way back in the early 70s.  He may have had a specially made carb
> though ... I know he had some funny name for it ... what was it ...
> "homogenizer" ????  You may want to check back through Popular Mechanics ...
> 
> HTH!
> Steve Buchholz
> San Jose, CA (USA)
This was a completely different beast!  The homogenizer was designed
for incredible fuel mileage.  Smokey was battling pressures caused by
expansion of heated fuel, an engineer's version of the Pogue
carburetor.
Shannen

------------------------------

Date: Thu, 29 Jul 1999 08:51:16 +0800
From: dzorde@xxx.com
Subject: Re: #437 Carby / supercharger

I've seen the crushed floats as well, although they were the plastic variety,
this one is brass so I think it should be OK.  According to all calculations
there should be around 16-18psi boost (if the s/c can sustain it).  I was
thinking of a 3 port regulator but don't know if they come in anything as low as
6-8psi for a carby.  Actually talked to a guy last night who told me that there
is a mechanical pump available, that drives of the crank belt so that pressure
increases as revs increases.

I will be efi'ing the car if the set-up works.  At the moment I don't know if
it'll work and so I don't want to spend money and time trying to get an efi
system going until I have proven that the engine will last and it can generate
enough power to make the car competitive.

I still haven't quite comprehended the carby thing yet, but pressurising the
whole setup does seem to work till boost exceed fuel pressure at which stage it
obviously runs out of fuel.  As for a tbi unit, I'm sure I could make a system
of a small Jap car work.

Thanks for the effort up to this stage.

Dan  dzorde@xxx.com

<Date: Wed, 28 Jul 1999 06:45:42 -0400
<from: "Charles  Brooks" <cbrooks1@xxx.net>
<Subject: Re: DIY_EFI Digest V4 #436
<
<Hi Dan, I'm nearly certain that the Float will have to be replaced or modified
so id doesn't crush <under boost. I'm slowly putting parts together for a twin
turbocharged small block Chevy (And I'm <selling a complete single turbo system
for a SBC to finance the TT project, if anyones interested <contact me off list)
and one gentleman I ran into showed me a float from a 2bbl Holley that was on
his <Turbo Ford 2.3, the float looked like someone had stuck a straw in it and
sucked REALLY hard :)
<
<You do have to reference the regulator off of boost however, if you run more
boost than the pump itself <can handle...  The home grown turbo projects I've
seen have been on V8's and used a mechanical pump <that was modified to accept a
manifold pressure reference. The Holley Mech. pumps are easily <disassembled for
the mods. I'm not sure if you could use a high pressure EFI pump with a low
pressure <regulator or not. If you do, make sure the regulator is a 3 port (Or
more) design that has a bypass for <fuel to return to the tank. That way the
fuel flow will cool the EFI pump, if you use a "Deadhead" <regulator with no
bypass the pump will probably overheat and be damaged.
<
<I'll take a look at some of my parts books and see if I can find a regulator
that looks like it'll <work. How much boost are you thinking of running?
<
<Charles Brooks
<
<------------------------------
<Date: Wed, 28 Jul 1999 11:44:33 -0700
<From: "Buchholz, Steven" <Steven.Buchholz@xxx.com>
<Subject: RE: Some efi: carby/super charger setup
<
<... by no means would I consider myself to be an expert on carburetted
<systems ... but there is one issue that seems quite apparent to me.  The
<float bowl of the carb is running in atmospheric pressure, so as you
<increase carb inlet pressure above atmospheric it sure seems to me that
<you're going to start pushing fuel (& even air) back into the bowl.  I don't
<know how you're going to be able to work around this pretty fundamental
<issue.  The carb is trying to meter fuel using Bernoulli's principle, so
<pressurizing the bowl would probably cause other problems.
<
<I wouldn't worry about the float collapsing under pressure, but it might
<tend to sink a bit lower in the fuel when the bowl is pressurized.  You
<would also need to have a fuel pump that was capable of overcoming the
<pressure in the bowl as well ...
<
<The simplest solution I can come up with would be to replace the carb with
<some sort of TBI unit ... but I don't have any suggestions as to the best
<source of such a system for a blown Fiat ...
<
<I know Smokey Yunick had a system where he put a turbocharger in front of a
<carb way back in the early 70s.  He may have had a specially made carb
<though ... I know he had some funny name for it ... what was it ...
<"homogenizer" ????  You may want to check back through Popular Mechanics ...

------------------------------

Date: Thu, 29 Jul 1999 12:06:25 +0800
From: dzorde@xxx.com
Subject: Haltech temp sensor

Hi all,

Have another favour to ask from a friean in the Fiat club.  Has anyone found a
commercially available sensor that will replace the Haltech air temp sensor.
This is the temp curve required:

100C -> 185 ohm
> 70C -> 450 ohm
> 38C -> 1,800 ohm
> 20C -> 3,400 ohm
> 4C -> 7,500 ohm
> -7C -> 13,500 ohm
> -18C -> 25,000 ohm
> -40C -> 100,700 ohm

I would have thought Haltech would use something commercially available, VDO
sensor, Bosch sensor, nippon denso sensor ?

Dan  dzorde@xxx.com

------------------------------

End of DIY_EFI Digest V4 #438
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