Terminator or factory ecu?

[OrbitOJ]

For a stock ls crate motor, does anyone have thoughts on which is better for all around drivability? I would have to image the GM engineers put a lot of effort into making the motor perform under all scenarios and not just WOT. Curious to hear if anyone has actual A/B experience with this.

[Bthomas]

Either will work great in that scenario. Main diff is the holley is considered to be easier to tune, so if you are constantly changing things up, its the better option.

The oe controller might edge it out slightly for a super basic daily driver due to the maf.

[Zachalanche]

I have a GM ECU on my 418 stroker, and the terminator X on my 5.3 (with mild truck cam).
Terminator is simple and easy to work with, but some have a pesky problem with not enough voltage being supplied to heat the O2 sensor. I was able to tune around this, but you have to disable closed loop operation until the O2 naturally warms up. Also there seems to be some parasitic draw on my battery that I am living with, after a couple weeks of sitting my battery will be dead. This is not the case if I disconnect the terminator. On the + side there's some cool things you can do with its outputs. I'm running a PWM fan with it and that works pretty slick. - this can be done with the GM ECU (easy in the tune, but difficult in the wiring compared to the terminator). Despite the issues I listed, I daily drive this vehicle, and it hasn't let me down, and it works pretty well.

The GMPP is much more sophisticated....and tuning it requires a bit more knowledge. Being able to read the MAF helps with street tuning as more air flow generally = more HP. On my 418 it does very well and it actually gets reasonable fuel mileage. I also like that the Check engine light is functional. Its probably easier to replace if you brick it- the terminator always has a long lead time.

Just depends on your abilities. just because of the terminator issues I have had, i think the GM ECU is better.

[Jk918]

The haltech rebel Ls is another option to consider, reviews seem good and I've heard good things about there customer support in comparison to holley, they just don't have the market share.

[kawasakii]

The GMPP is much more sophisticated IMO..Had a hard time understanding it.

[streetk14]

I’d say go with a GM ECU and a harness from a solid company like Speartech. I wouldn’t do one of the GMPP ECUs, as they are different than a factory GM ECU and are limited in a number of ways. Only reason I’d go aftermarket is if you want some of the extra features. For me factory-like reliability and very in depth tuning capability (if you or someone knows what they’re doing) take the win. I wish my E38 (2015 Z28 application) had wideband 02 sensors, but that’s about all I’d ask for.