[Gmecm] TBI conversion

[Steve Ravet]

> -----Original Message-----
> From: gmecm-bounces at diy-efi.org 
> [mailto:gmecm-bounces at diy-efi.org] On Behalf Of Rick McLeod
> Sent: Thursday, November 30, 2006 10:59 AM
> To: gmecm at diy-efi.org
> Subject: Re: [Gmecm] TBI conversion

www.jagsthatrun.com has a lot of EFI conversion parts like VSS, also
various mechanical bits, and plumbing elbows and straights for MAF
sensors.

> 
> 
> Currently uses a 1226865, target using a 1227747/1228747 ECM 
> (very common unit) Painless Harness 60101 (they engineered 
> wiring based on a 90 Chevy P/U for the 1227747 as well as 
> other similar ECMs) Holley TBI adapter 17-41 or (Painless 
> 60118) (solves the bolt pattern match issue) Painless VSS 
> Adapter 60115 (gets 2PPM from mechanical speedo cable), car 
> may have an acceptable feed already since CCC may require one 
> ThrottleBody from same size engine or modify cal on PROM to 
> change inj size PROM from same size engine (I can modify to suit)
> Sensors/inputs: Knock, TPS, Temp, MAP, Spark, Speed
>    I would intend to make a plate to mount fuses, relays, 
> MAP, etc onto to make installation clean
>    * Knock sensor exists
>    * TPS should be part of the TBI
>    * Coolant sensor (this is still an outstanding question, 
> will the existing one suffice - I think so, if not acquire 
> correct one)

The computer and dash cannot share a sensor, so you'll probably need
two.

>    * MAP sensor (this is still an outstanding question, will 
> probabally have to acquire correct one) My sources show a 
> valid 90 TBI 305 P/U part # as  OEM to be 16137939 but the 
> parts houses show it to be 16137039, so am a little puzzled here

MAFs for TBI and TPI normally aspirated are all the same, although they
come in different packages.  Any one of them would work for you.

Get the factory service manual that corresponds to the donor ECM and its
calibration.

--steve