HOLLEY EFI plug and play with CRUZ Performance engine harness for TURBO Buicks

HOLLEY EFI plug and play with CRUZ Performance engine harness for TURBO Buicks

CRUZ Performance has designed and developed a plug and play engine harness that will allow you to use the HOLLEY Dominator ecu or the HP ecu.The harness is a direct plug in for all your factory engine sensors and fuse box that will retain all your stock accesories.

The base harness is $650 and will only be sold with purchase of HOLLEY ecu from CRUZ Performance.The HOLLEY ecu gets its power and ground from 10 gauge wire that attaches at the battery.(this eliminates the voltage issues that other brand ecu's have when using adaptor boxes with faulty 30 year old wiring)

CRUZ Performance has designed and developed this harness to remove your 30+ year old weak stock cut up harness to only work with the HOLLEY smart coils (6 individual coils are needed).The HOLLEY smart coils are far superior than a stock ignition module or any replacement coil kits available for the turbo buicks.CRUZ Performance makes a hotwire smart coil harness that gets power directly form the battery.

HOLLEY Dominator or HP ecu's are self tuning with data logger and dedicated fuel and oil pressure inputs.

Holley ecu's feature (may require additional parts)

* boost controller

* boost bump

* Integrated water/methanol injection control

* Integrated electronic transmission control--currently can control GM 4L60E and 4L80E (Dominator only)

Most Turbo Buicks will only need the HOLLEY HP ecu to control the basic needs of everyday daily driving.For the Turbo Buick owner that needs an extensive amount of inputs and outputs the Dominator ecu will allow for limitless combinations of options that will be able to be used as a complete data acquisition system .

contact CRUZ Performance for pricing and all options










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It's a really nice harness! Mine is in the car. It drops right in. It has enough length for the main trunk line to be routed over the heater box away from the downpipe. If I ever decide I don't like that, it's not a big deal to rerun in the stock location stock either. I have some custom stuff to finish up, hopefully soon she'll be on the road again. I took a bunch of pictures during the install, hardest part so far was removing the 2 bolts holding the inner fender on under the a/c/heater box. Just the harness alone made the change to Holley worth it so far!
I've been driving this setup all summer, a/c and stock fan on just a low relay circuit via the Holley output/Cruz harness. I haven't needed the high fan, but I could run that on a switch if I ever wanted too. Fires right up, super smooth idle, and easy to tune. It has tons of features. Never going back to stock...
More and more I'm really glad I switched everything to the Holley setup. So, the learning, it's great and all, but you can manually tune the mid rpm/light load fueling and turn down or turn off the learning so you can just have learning when you get on it, to whatever amount you want. That way you can fine tune how it cruises around town and lock it down there. My stall is 3100 at 0 boost, and then once moving its really gets going in engine speed even with the TPS under 10% and pretty good vacuum pulling away from a light etc, so I don't want it to relearn if the road is hilly and ever changing at those light load conditions.

The base fueling table and the learn table, those get combined as one, and really easy to follow the hot dot in realtime of what the ECM is using so you can tweak it while keeping an eye on the wideband to see how its pulling fuel or dumping too much to correct by target a/f to the base fueling. Once you get the hang of it its pretty easy. I haven't really tweaked the IAC/throttle screw other than set it up the first time. The logging is right there, just pull it up.

I dropped my idle down to 775 rpm once its warmed up, purrs like a kitten even with 120# injectors and a low 9 sec cam and TSM race ported alum heads.

The other thing is you can hop on the Holley forums and tons of info there and fakebook. Everyone is boosted LSx so all the combinations have info on how to do stuff, boost scramble, wastegate setups, etc. There are even classes you can take at the Holley factory in BG on how everything works.
Jim I hope you can get to the track with her sometime soon!!!!
Keep us posted!!
Jim I hope you can get to the track with her sometime soon!!!!
Keep us posted!!

l have a list of things to do to the car this winter. Still on the TE45a.63 from 2004. Still on KYB shocks from 2000 and both stock sway bars are on the car. I've only taken it to 14.3 psi boost on pump 93, no doubt it still a 10 sec car at that level with new heads and cam on 93. It didn't even want to throw fuel at it, 0.1-0.2 on the learn at those cells.