Tuning E38 vs Holley

[BMWMD82]

Hey guys. I?m not sure this is the best place to post this, but I was hoping for some real world feedback.

I?m looking to do an LS3 stroker build for my 68 Firebird, and am debating whether to go with a factory E38 ECU, or something like Holley HP. I?m starting with nothing, so I can go either route.

For what it?s worth, I?ve tuned several forced induction E38/LS3 cars, so I?m pretty familiar with that. I also have some experience with Holley?s EFI software, as I have their Sniper system on the car currently.

Anyway, just looking for pluses and minuses. Mainly driveabiliy and reliability. Can Holley match the factory ECU in these areas?

Thanks

[kevin87turbot]

Hey guys. I?m not sure this is the best place to post this, but I was hoping for some real world feedback.

I?m looking to do an LS3 stroker build for my 68 Firebird, and am debating whether to go with a factory E38 ECU, or something like Holley HP. I?m starting with nothing, so I can go either route.

For what it?s worth, I?ve tuned several forced induction E38/LS3 cars, so I?m pretty familiar with that. I also have some experience with Holley?s EFI software, as I have their Sniper system on the car currently.

Anyway, just looking for pluses and minuses. Mainly driveabiliy and reliability. Can Holley match the factory ECU in these areas?

Thanks

You have several benefits by going to the Holley system An integrated wideband is the more useful upgrade. You might also consider a Terminator X.
Which transmission are you going to run?

[BMWMD82]

The wideband functionality is the one thing that would be very appealing. Makes fuel map tuning on the Sniper very easy, and I also really like having closed loop control at WOT.

The plan is to run a manual trans, most likely a TKX 5 speed. I know the Holley ECUs have a lot of additional features, but this is a basic street car that probably won?t benefit from most of it.

[BMWMD82]

I was just looking into the Terminator X. Looks like it is a little more basic and reasonably priced.

I guess my questions for anyone who has used it are how does it compare to a factory E38 when it comes to:

1) dialing in drivability on a cammed engine

2) reliability

[kevin87turbot]

I was just looking into the Terminator X. Looks like it is a little more basic and reasonably priced.

I guess my questions for anyone who has used it are how does it compare to a factory E38 when it comes to:

1) dialing in drivability on a cammed engine

2) reliability

I've had great success with them. I run one on my own car as well. It has pretty much anything that you'd need for an application like yours.
It's very easy to dial them in...easier than HP Tuners.

PM me if you're interested in one.

[BMWMD82]

Thanks for the info.

How has the reliability been? I am mostly worried about weird electrical bugs like my Sniper. While it is maybe an apples to oranges comparison, the Snipers are well known to be very susceptible to EMI/RFI, causing lots of strange issues. The Sniper is an integrated ECU / throttle body TBI setup, so the ECU is very close to the distributor, plug wires, etc.

A Terminator X mounted inside the passenger compartment should be far less susceptible to EMI, but it still makes me a little nervous buying another Holley EFI system. I have never heard of anyone having this type of issue on an LS swap with a factory ECU; regardless of the ECU location.

[alan91z28]

Thanks for the info.

How has the reliability been? I am mostly worried about weird electrical bugs like my Sniper. .

While I do not have direct experience with Terminator X, I do have experience with Holley HP which I believe the terminator to some degree is derived from... I had nothing but trouble with the Holley HP including being unable to get rid of an intermittent cut-out that was introduced as part of their software upgrade and still hasn't been fixed by Holley in their latest release according to the forum even though the issue is well over a year old (this is on a HEI system)... I got so frustrated I ended up yanking out the Holley HP and had my project running better in 2 days with an OEM type setup vs struggling with the Holley over 18 months.

Also a friend of my had his Dominator "lose" its programming when his wife had taken his truck to the supermarket... the Dominator and HP (don't know if Term X has this) has an issue where under the right sequence of events at power down it can lose its programming

I have a lot of projects and my plan had been to use Holley HP for all my SBC and LS projects but completely ditched that and stuck with OEM type. Holley has some nice features, but also it has quite a few issues in my opinion and also a pretty limited control set in the idle area, etc FWIW

[BMWMD82]

Thanks. This is the kind of thing that worries me. The factory ECUs just plain work, seem much less susceptible to issues with interference, and are much less picky when it comes to wiring (power supply, etc.). Holley tech support is also very painful to deal with if you do have issues.

Well, I guess I have some thinking to do. I really like integrated wideband concept and simplicity of the Holley software, but that is all worthless if the system is not reliable.

[Ben Charles]

Nothing compares to OeM ECM for drivability…. Been 4s in 1/8 and 7s in 1/4 on stock ECM stuff

[Leva]

Do not mean to derail the thread, but does anyone have any insight on a fueltech setup compared to holley compared to stock? In my circles, holley is a problamatic system compared to a fueltech setup.

[10_SS]

Nothing compares to OeM ECM for drivability?. Been 4s in 1/8 and 7s in 1/4 on stock ECM stuff

I run a Megasquirt MS3X on my Whippled LS3... driveability is much better with this because you dont have the lean/rich narrowband 02's switching constantly... if you run a manual trans or lock the auto TCC, then accelerate lightly to moderately (before stock PE kicks on) from low RPM you can feel the rich/lean spikes of the stock trims creating surges in power on all engines, stock or modified. Another place you really notice the surging from stock 02 lean/rich switching is campgrounds where your often trying to maintain very low speeds, often either cruising or climbing hills slowly.. you can really feel it in certain scenarios, once you notice, it really pisses you off! lol

Running the closed loop wideband solves this problem because you can hover very consistently around whatever AFR points you want. The only way I was able to do this with any narrowband 02 feedback system is disable it.. then it runs very smoothly, just not consistently where you want AFR.

Regarding the reliability, I piggybacked the MS3X to control fuel only.. then just unplugged the stock injector wires and pushed aside, ran new ones for the MS3X. If anything ever goes wrong, I can just switch back to the stock ECU. I run stock ECU for spark ,since the stock knock system is the best available.

However, I recently thought about switching spark over to the MS3X and using my custom ESP32 based "Gauge" (and Harry's Laptimer Engine Data interface) to read the knock PID and forward that to the MS3X to trigger it's knock retard.. I just don't know if 21hz is fast enough to catch knock events efficiently enough to stop audible or damaging knock as fast as the stock ECU does. I suppose I could add another ESP32 and have it only doing one thing, very fast.. ---> listening to the knock PID and sending it to MS3X, at 50-80hz.

Another thing that is very useful with realtime ECU tuning is injection timing. I was able to optimize my idle and part throttle injection timing in 3 minutes! Just tweaked it while running and watched my "Fuel Correction" drop from 100% to 94% (using 6% less fuel to maintain the same AFR) just from changing the injection timing values as it's idling. People spend many hours trying to dial that in on stock ECUs. They are such a PIA. I hate them, but it's there incase I need it!