LG4 to L03 swap
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From: Germany, nearby Saarbruecken
Car: 87 Firebird Formula
Engine: TBI, V8, 305cui, w. A/C
Transmission: TH700R4
LG4 to L03 swap
Hi !
Would like to swap from 87 LG4 (Firebird w/TH700R4) to 91 L03 (out of a 91 Firebird w/ manual trans.).
Would like to let the 87 interior wiring harness inside the car. Only ECM and engine harness will be exchanged and the needed adds (stand alone elec. fuel pump, tcc, ...) will be done.
So we have to re-code the pigtail of the 87 interior harness to make it fit to the 91 ecm and to be able to add the inj1 + inj2, vats and fuel pump fuse connections.
Are there any gm pigtails available (male and female ?) to be able to built a "re-code bridge harness" ?
One of the goals is to make it possible to swap back to LG4 as easiest as possible (if necessary).
P.
Would like to swap from 87 LG4 (Firebird w/TH700R4) to 91 L03 (out of a 91 Firebird w/ manual trans.).
Would like to let the 87 interior wiring harness inside the car. Only ECM and engine harness will be exchanged and the needed adds (stand alone elec. fuel pump, tcc, ...) will be done.
So we have to re-code the pigtail of the 87 interior harness to make it fit to the 91 ecm and to be able to add the inj1 + inj2, vats and fuel pump fuse connections.
Are there any gm pigtails available (male and female ?) to be able to built a "re-code bridge harness" ?
One of the goals is to make it possible to swap back to LG4 as easiest as possible (if necessary).
P.
Last edited by Patrick Freitag; Nov 5, 2008 at 10:21 AM.
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From: Moorestown, NJ
Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
Re: LG4 to L03 swap
I think the biggest differences are likely to be in the engine/ECM harness itself as opposed to the interior wiring harnesses. If you wanted to you could just leave the CC Q-Jet and stock wire harness in place and put the new TBI 305 underneath it (your current intake may even fit the newer TBI motor).
As far as the fuel injection goes, the easiest way is to simply re-pin the ECMs main connectors and run the additional wires (injectors, fuel pump, IAC, etc.) in parallel to the exisitng harness. This way you minimize the disturbances and if you want to go back to using a CC Q-jet, you can simply revert back to the stock ECM connectors and pin configuration. Many sensors used on the CC q-jet are similar to the ones used on the TBI car.
As far as the fuel injection goes, the easiest way is to simply re-pin the ECMs main connectors and run the additional wires (injectors, fuel pump, IAC, etc.) in parallel to the exisitng harness. This way you minimize the disturbances and if you want to go back to using a CC Q-jet, you can simply revert back to the stock ECM connectors and pin configuration. Many sensors used on the CC q-jet are similar to the ones used on the TBI car.
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