[Diy_efi] Olds 403 MPFI Project

[Christian E. Carson]

This is a doable project using all junkyard parts. You just need a lot of
time to gather the parts, and a lot of patience to assemble them and tune
the beast.
For reliability and ease, I would highly recommend using the stock intake
off a 1976-1980 Seville. These cars came with the only factory MPFI Olds
engine (it was a 350.)  You can even use the stock injectors with a minor
modification to the ECM.
I just did this on my 1990 Olds Custom Cruiser's stock 307, just to see if I
could. It starts and runs, but the 307 is in a poor state of repair and I'm
now pulling it in favor of a diesel (gotta beat those gas prices).
Anyway, here is what I did:
1227749 ECM from Turbo Sunbird/Syclone/Typhoon. Modified as per instructions
on this website: http://mywebpages.comcast.net/p-928/749mods.html (Bill is
still on this list, IIRC, he can state that this modification has lasted him
thousands of miles in his Porsche.)
Stock Seville 38 lb injectors.
Wiring harness from 86 Camaro TPI (any 86-92 will work really, all of them
need some modifications).
TBI unit from Chevy 4.3- 5.7 mounted to intake with adapter.
External fuel pump from 89 Ford truck drawing from a surge tank fed by the
stock fuel pump. (The surge tank is a stock VW part:
http://scirocco.dhs.org/vw/pics/0-allyn/images/020510-154136-Z10.jpg)  You
can skip the surge tank part if you don't plan on going below 1/4 tank or
take any hard turns, but I'm a crazy, cheap driver so I considered this a
requirement.
The stock VSS will put out a 2000 ppm signal which can be input to the ECM
(you just have to find the right pin)
The stock knock sensor and filter can also be used, though I'm not sure how
well it would work on your 403. The pin isn't listed on any pinouts, but you
can find it in Ludis' site. I believe it's B8, labeled "ESCIO".  (Just
remembered - an '87 307 shouldn't have a knock sensor, so you don't have to
worry about that.)
You can't use one of the brackets on the A/C compressor, but I believe
that's about it.


Anyway, you REALLY want to look at this website:
http://www.grimers.com/vehicles/olds/403efi/index.html
It happens to be about nothing less than converting an Olds 403 to EFI in
the very way I mentioned above.

Chris
----- Original Message -----
From: EEOLAY5 at aol.com
To: diy_efi at diy-efi.org
Sent: Wednesday, August 17, 2005 7:30 PM
Subject: [Diy_efi] Olds 403 MPFI Project


Hello I am Theo.
      I am attempting to MPFI a 1979 Olds 403 for my 1987 Buick LaSabre
Estate Wagon. The finished project must support ALDL scanning, 200R-4 Tranny
Lockup and 49-State Emissions. The finished project will be a daily driver
for street use only. I would like to keep the project all GM-AC Delco using
Multec Injectors and related sensors. Will anyone with related experience
Please help me in getting this project started. The budget is limited to
building this thing reasonably. All comments are welcome.
Thanks,
Theo.