Holley Terminator vs. EEC/Quarterhorse vs. Megasquirt

Okay so, I'm just thinking ahead at this point; my car is still slumbering.

In the past, I was dead set on using a factory computer with all its inputs correct and intact, for example, MAF and O2s. I didn't like the idea that a Megasquirt doesn't use many of the factory inputs, even though it's many times smarter. The other thing I really didn't like about the Megasquirt was the fact that it's up to you to get it running correctly. No thank you. My assumption with an EEC was that at least you start with a pretty good foundation/tune that will run decently well and you only need to tweak little things from there to get the most out of your engine.

BUT... since I made that decision, I've been reading a book about tuning, and the book seems to assume that you will be starting from scratch anyway. I only got about 2/3 of the way through, so I will grant you that I don't have the whole picture. I DO NOT WANT TO START FROM SCRATCH. I want to enjoy the car now, not have to be doing significant fiddling with tables in perpetuity to even get it to rev like a factory stock car should. And if I do have to do that, the Quarterhorse interface is clunky compared to what you get with a Megasquirt or Terminator. The reason I have EFI over carb is so that I don't have to fiddle!

I also since found out when a tuner typically tunes an EEC IV, one of the first things they do is lock it in open loop anyway, so it's not even using many of those inputs I thought were so important!

I was looking a bit into the Terminator, and there is a phrase in there that is very appealing to me. SELF LEARNING. But my question is, is it that simple? Plug it in and go?!

Background on my setup: It's a SEFI 306 w/GT40P heads both pistons and heads tweaked an indeterminate amount for additional compression. Cam is a Flowtech for a P head 302. 24# injectors, Explorer intake and TB, 70mm Cobra MAF. Pretty much a Cobra engine right? So I thought it would be best to run an X3Z computer. I currently can't get the MOFO to idle, I don't know it's related to any sort of computer or sensor mismatch. To be really honest I wouldn't be doing any "tuning" at all if I had my way, but I thought it would help get the most out of my engine.
 
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Self learning means that it can tune the fuel table for you. There is always tuning to do
Is there a closed loop version MS? Always being in open loop seems like it would have some of the same disadvantages as a carb with altitude and temp changes. A 4x4’ing cousin and old school hot rod maker used to put factory TBI conversions on for those reasons. (Not sure what he is building lately.)
Please enlighten me about what’s current, guru.
 
Yes it has closed loop idle, ego correction, barometric correction, mat temp correction and can be tuned in any manner.
Even MAF you can tune the MS systems in mad mode if desired and then add a speed density map to the maf map if boosted.
The possibilities are only limited by knowledge in the software.
 
I have a terminator x I'll be installing on my 90 coupe at some point. I like the idea of having all new wiring.

I know I'll still have to get the car fine tuned. But that shouldn't be a problem getting a remote tune.

I can't imagine my HCI on a stock AL9 ecu without a chip/tune is running near it's potential.
 
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I just watched this video.


View: https://youtu.be/Xbo5qgDQ1pU


you know, it's funny. I've been more focused on dealing with the hardware under the hood. In my mind, these electronics minus the new shortblock and cam ran just fine with my old engine. So it doesn't make sense why it wouldn't now unless I messed something up installing the new engine.

I hadn't considered that there could be a solution in the computer. Honestly, I just didn't know that much about what all you can do in there. All those idle parameters he goes into, I didn't know about any of that. The only thing is, he's talking about a dealing with a pretty radical cam, when I was under the impression the cam I have really shouldn't be that big of a leap vs. stock. I wouldn't think going into the software would be necessary, but the more comfortable I get with it, the more optimistic I am that I can actually do something about this. I didn't even want to plug in the chip until I was sure I'd exhausted all the physical causes, which is probably correct, but I didn't see a way out of the tunnel before, and I do now.
 
I have the terminator x in my car and it self learns to a certain degree. You do have to to fine tune any of the holley systems, installed 3 different versions on 3 different cars and they all needed some type of fine tuning adjustment.

The terminator x is a great starting point though and has a ton of features main downsides out of the box it's not setup for the factory pwm iac, but it tells you this in the instructions and what you have to go into the tune and do. Also the idle and iac ramp down tables don't directly match up like the Ford factory setup so you have to go in and adjust that as well.
 
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Okay so, I'm just thinking ahead at this point; my car is still slumbering.

In the past, I was dead set on using a factory computer with all its inputs correct and intact, for example, MAF and O2s. I didn't like the idea that a Megasquirt doesn't use many of the factory inputs, even though it's many times smarter. The other thing I really didn't like about the Megasquirt was the fact that it's up to you to get it running correctly. No thank you. My assumption with an EEC was that at least you start with a pretty good foundation/tune that will run decently well and you only need to tweak little things from there to get the most out of your engine.

BUT... since I made that decision, I've been reading a book about tuning, and the book seems to assume that you will be starting from scratch anyway. I only got about 2/3 of the way through, so I will grant you that I don't have the whole picture. I DO NOT WANT TO START FROM SCRATCH. I want to enjoy the car now, not have to be doing significant fiddling with tables in perpetuity to even get it to rev like a factory stock car should. And if I do have to do that, the Quarterhorse interface is clunky compared to what you get with a Megasquirt or Terminator. The reason I have EFI over carb is so that I don't have to fiddle!

I also since found out when a tuner typically tunes an EEC IV, one of the first things they do is lock it in open loop anyway, so it's not even using many of those inputs I thought were so important!

I was looking a bit into the Terminator, and there is a phrase in there that is very appealing to me. SELF LEARNING. But my question is, is it that simple? Plug it in and go?!

Background on my setup: It's a SEFI 306 w/GT40P heads both pistons and heads tweaked an indeterminate amount for additional compression. Cam is a Flowtech for a P head 302. 24# injectors, Explorer intake and TB, 70mm Cobra MAF. Pretty much a Cobra engine right? So I thought it would be best to run an X3Z computer. I currently can't get the MOFO to idle, I don't know it's related to any sort of computer or sensor mismatch. To be really honest I wouldn't be doing any "tuning" at all if I had my way, but I thought it would help get the most out of my engine.
I had the same thoughts when looking for a tune for our 1994 GT. Wasn't really impressed with any of the offerings but eventually was put in touch with Ted Jenkins from Tuning Innovations who specialises in the 1994-98 Mustang, but also tunes other efi equipped fords. You should give him a call before you pull the trigger on any other system.
 
Thanks. I think I'm going to see where things go with the Quarterhorse I bought when I started down this road with the X3Z.

I think I am starting to get that you start in about the same place with whichever setup you end up with. There are sample tunes available, and you tweak it from there. The closer your hardware is to what the computer thinks you have, the less you have to tweak it. Plus there are places where you can TELL it what you have such as what injectors and how much air is getting in through your throttle blade. I've had miscommunications with people where they can't figure out why I'm not already datalogging and making changes from what comes up in the logs. I wasn't familiar enough with what all you can do with tuning software to even know where to start with that though.

Brew2l from youtube says that it takes quite a bit to upset a factory computer to the point it doesn't want to run right. That's what I figured about my setup. I thought there shouldn't be much reason the thing won't idle well. but the fact remains that it won't. I guess we just take note of that and move on.