I am a big fan of Holley EFI and I am currently running it on my other(non Buick) car. I wanted to put Holley EFI on my GN also so I contacted Cal Hartline(Hartline Performance). Cal is a Holley dealer and he has a lot of experience tuning Holley EFI, but since no one offers a plug and play harness(yet) Cal had not worked with one on a turbo Buick. I bought a Holley HP ECU and unterminated harness from Cal and I modified a Casper’s XFI adapter to work with the Holley HP. The Holley HP system is pretty much a plug and play system using the modified adapter harness that I made/modified. The only thing that wasn't plug and play was the power and ground for the ECU. I think that could be integrated into the adapter harness also, but since my battery is in the trunk and I am putting the ECU under the rear seat it was easy to do so I just wired it directly to the battery like Holley recommended. I did not need to modify the factory engine harness. Cal provided a start up tune for the Holley EFI and when I got ready to fire the car up Cal and I set up a time when Cal could connect to my laptop remotely and he had the car up and running in no time! I expected there to be some potential problems since I was going with a set up that was out of the norm on turbo Buicks, but it really went very smoothly. I ended up with less money in the Holley HP set up then I would have had with an XFI and the Holley HP can drive CNP ignition with no other boxes to buy which is going to be my next project. There is just no substitute for buying from a quality vendor that supports our cars and has first class customer support, thanks Cal!
87 GN up and running on Holley HP EFI!
- Thread starter Steve
- Start date
The Holley HP ECU is a little cheaper than the XFI, but I don't think it would be a lot cheaper by the time you get everything you need. The Holley HP does come standard with internal logging and the SW updates are at no cost. The Holley HP can also run CNP ignition without having to buy another box like is required on XFI so that could be a savings also, but only if you plan to go with CNP(which I am planning to do later). Currently there is not a plug and play adapter harness for the Holley system but I believe Cal is looking into that and the adapter would probably be about the same price as the XFI adapter because it would be very similar except it would have Holley connectors instead of XFI connectors.
Cal is looking into offering the Holley HP as a plug and play set up for turbo Buicks so that may be available soon!
