Aftermarket EFI systems
Thread Starter
3rd Gear
Joined: Jun 2018
Posts: 3
Likes: 0
Aftermarket EFI systems
If I install a Edelbrock pro Flo EFI system w/ ECU in my 90 corvette coupe, what do I need to do with the existing ecu wiring? Do I remove the existing ecu harness and toss it or do I need some of those wires?
Any advice would be greatly appreciated.
Thanks
Any advice would be greatly appreciated.
Thanks
Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
I think you need to refer to instructions. If not required i would carefully remove and box oem harness and ecm. You might need it if you unhappy with Holley efi. You could sell the oem efi to recoup some of your costs
Melting Slicks
Joined: Dec 2008
Posts: 2,772
Likes: 64
From: Mystic CT
What kind of power increase are you looking for with the mechanical mods. An ECU properly tuned does not make more power than another ecu properly tuned given both are suitable for the engine. Under 500 hp NA I fail to see what you might gain over the factory one properly tuned. If your '90 is like my '91 it is speed density so no mass air flow sensor to get in the way. Moats, Tunercat and no doubt others have the tools needed to tune the factory ecu just fine and you need to learn either system.
Thread Starter
3rd Gear
Joined: Jun 2018
Posts: 3
Likes: 0
Thanks guys. I already bought the Edelbrock system, it was a package deal that comes with distributor and ecu. You can adjust air/fuel delivery and timing from a tablet. I got a deal. I would really like to use the whole system if possible. The only two wires I think I need to find are ignition on/start and tach. I was hoping someone had done this before that could tell me if I can just remove the c100 harness or if there were wires in there I need also.
Thread Starter
3rd Gear
Joined: Jun 2018
Posts: 3
Likes: 0
Thanks kevova.
I think I’m going to leave the existing ecu in place, pull the existing engine wiring harness, mount the new ecu right on top of the old one and run the new engine wiring harness right from there. That way if it all goes south I can back out of it somewhat easily.
I should be able to run it as a stand-alone system and abandon everything from the ecu back through the firewall. If I need it again it’ll be there. The new ecu will run the fans, fuel pump, and everything else on the motor.
If I’m making a huge mistake please let me know.
thanks
I think I’m going to leave the existing ecu in place, pull the existing engine wiring harness, mount the new ecu right on top of the old one and run the new engine wiring harness right from there. That way if it all goes south I can back out of it somewhat easily.
I should be able to run it as a stand-alone system and abandon everything from the ecu back through the firewall. If I need it again it’ll be there. The new ecu will run the fans, fuel pump, and everything else on the motor.
If I’m making a huge mistake please let me know.
thanks
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
As you peal the oem harness back to the ECM, you will find were the wiring ties into underhood fuse block. The you could remove it all at once. I don't think there is space for both under the hood.