Intro and project

[Bob Valentine]

I was just looking around the diy_efi site  when I found this list has been
created.  I've been lurking around the diy_efi list since it was started,
and am now finally getting my own project off the bench (litterally!).
Once I have a basic running system, I plan on doing some serious hacking
with it.  A recently aquired spare motor may allow me to do some inital
testing out of car.

I've got a '71 Cutlass which has been slated to get FI for quite a while.
 I originally had a 350 (now a 403), and was going to use a intake from the
75-80(?) FI Olds 350's found in Caddy Sevilles and a few others.  This
system was a port injected system with a analog GM/Bosch ECU and wasn't
known for much except running like crap and tending to catch on fire.
However, I figured that this could at least provide the intake and fuel
rails for a SB Olds - save the trouble of fabricating intake and fuel
rails.   I planed to control it with a GM TPI ECM.     The intake design is
almost a single plane design; it looks like it'll flow pretty well.

I've since aquired a '89 Firebird ECM, harness, and most sensors.  ECM is a
165, cal is ABYA 5400.   From the F-body list, it looks like the cal is 350
MAF, TH7004R, 2.77 rear.  I have adapted a throttle body from a TPI to the
intake.    This is pretty close to what I have now - I'm running a TH700-4R
(i manually engage the lockup) and have a 2.78 rear in the car.  I have
adapted a TPI throttle body, so that resolves TPS hookup and IAC.    I can
use a distributor from a CCC Olds 307, since it uses the 7-pin module.
02 sensor already welded in the exhaust pipe, I will switch to a 3-wire
(heated) soon, since my DVM shows it takes a long time to warm up.

I have yet to determine if "late model" (eg, 85 and up TPI) injectors will
fit this fuel rail - the injectors right now are Bosch.  Should know this
week.

Now for the questions, in no particular order:

1.  What do I do for VSS?   I need the mech. drive for the speedo.
2.  Do I stay MAF, or get a cal for speed-density?  I have no problem
ducting the MAF sensor, and I have 2 known good units.
3.  I've changed out the 350 for a later 403 motor.   Will the 350 cal work
if I bump the fuel pressure a little, or will I need larger injecters?
4.  Will the TPI throttle body flow enough for the 403?  The motor is
fairly close to stock (it's a mystery motor.  All I know is that it was
"rebuilt"), iron manifolds and full duals out to the back.
5.  Should I stick with the 165, or try and get a later unit?
6.  If TPI injectors won't work with my fuel rail, are there any large
enough Bosch units for my needs?

I realize this message crosses spans the diy_efi list AND the gmecm list,
but I'll start here.








--> Bob Valentine
--> bob at tecmark.com