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Holley Terminator x or Hp EFi for 6 cylinder

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Old Feb 25, 2026 | 11:14 AM
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Holley Terminator x or Hp EFi for 6 cylinder

I am going to put a Holley efi kit on my 2.8l v6 that has a small supercharger on it. I was thinking of putting the Terminator x kit but the support person at Holley said I should use the HP efi kit. Of course, it is $1000.00 more and looks like it is more work to make up the wires. Any input on either kit would be appreciated.
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Old Feb 25, 2026 | 09:40 PM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Did they give you a reason?

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Old Feb 26, 2026 | 07:12 AM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

He said that the HP efi was better for the v6 and the Terminator was mor for a v8. I heard that the Terminator can be used for a v6. He also said that it is better because I can make up my own harness.
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Old Feb 26, 2026 | 08:00 AM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Compare and contrast the features of both by reading the entire manuals. Either can run a 6 cylinder boosted application. The HP has more I/O, so if you run out of spots on the Terminator X, you'll end up spending the same as you would have on the HP to fix it, and you'll end up with less features.
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Old Feb 27, 2026 | 12:13 AM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Either ECU will work, I have no idea why it would be suggested that one ECU is geared more towards one cylinder count pver the other...

I would say that this sales person was told to sell through the HP ECU stock...

Biggest thing would be the IO you need. The HP ECU has a few more IO than the terminator. The Terminator is limited 4 assignable inputs and 4 assignable outputs, which while I have used all of the IO on an installation or two, I've never needed more, in the vehicles I've used Terminator Xs on.

the other difference would be if you were considering DBW or electronic transmission control, then the Terminator X Max is what would be needed, the Terminator X, and HP ECU wont control DBW or electronic transmission.

Is there a reason why you want to go Holley specifically?
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Old Feb 27, 2026 | 07:00 AM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

HP ECU does not have more I/O slots available, but the I/O is more configuable to different types.

Are you doing this because the shop doing the work doesn't know how to use the stock ECM? There are people that can tune with the stock ECM.
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Old Feb 27, 2026 | 07:12 AM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

I am thinking about the Holley because it is the only one that can do 6 cylinders. I am doing all the work myself, I did get tunning software and a chip emulator, but it is way over my head. Plus they do not run a wide band o2 and no map sensor. I am not planning on running tat may inputs or outputs. The X should be all I need,
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Old Feb 27, 2026 | 10:57 AM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

You won't escape having to learn how to tune. In fact it might even be harder with the Holley because you start from scratch with nothing. You're both the engineer and the tuner. At least with stock ECM you don't have to be the engineer, you're just a tuner.

The "self learning" of Holley is very over exaggerated in its ability to help you dial in a tune.
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Old Feb 27, 2026 | 01:31 PM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Since you already have a chip emulator, it could be worth a shot to try to get things running better on the stock ECM. I haven't read up much on the earlier style ECUs that the 2.8s came with, but I do know that people have managed to get wideband integration going with the later (3.1 style) Memcal '7730 ECUs. Gearhead-EFI is a great resource if you're looking for stock BIN files and in-depth OBD1 tuning info, and the TunerPro website should have the proper mask you need to read the BIN correctly (Gearhead should have it as well, alongside the stock BIN). The later '7730 ECUs did also run a MAP sensor, but you'd have to do a good bit of rewiring to get one of them working with your harness. You might be able to run different masks on your ECU to allow for wideband/ MAP sensor use, but again, I haven't read up on anything aside from the '7730, so I can't say for sure whether or not your specific ECU is as changeable.
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Old Feb 27, 2026 | 03:10 PM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

I thought that the Holley would be easier to tune. There is a shop near me that knows how to tune the Holley systems, so If I run into a problem I could have them tune it.
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Old Feb 27, 2026 | 06:29 PM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Yes, a lot of shops will know how to use the Holley software. However, you will find that a tune from a shop is mostly just idle and wide open throttle. Helpful for sure but daily driving manners will mostly end up being your responsibility to figure out. You will have to learn how to tune.... it is inevitable.

I'm not trying to discourage you, I'm just trying to prep you for the reality that you will have to learn to tune.
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Old Feb 28, 2026 | 09:10 AM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Thanks, Qwktrip I would rather someone tell me the facts. it does not discourage me. After looking at my options the Holley system looks the easiest to set up, and to start out with. It seems to have a ton of support through Holley, online chat rooms, and trained shops. Holley also offers online training. That looks interesting to me. I own a repair shop and learning a new skill may help me out.
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Old Feb 28, 2026 | 12:54 PM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Let us know if you have more questions. The traffic on this site has slowed down over the years but the remaining people are pretty helpful. In particular, @fasteddi is one of the people that got a 2.8L to run fast, so look for his threads from when he had the V6.
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Old Feb 28, 2026 | 05:25 PM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Originally Posted by dana0330
Thanks, Qwktrip I would rather someone tell me the facts. it does not discourage me. After looking at my options the Holley system looks the easiest to set up, and to start out with. It seems to have a ton of support through Holley, online chat rooms, and trained shops. Holley also offers online training. That looks interesting to me. I own a repair shop and learning a new skill may help me out.
I had alot of luck with a 7730 stock ecm and a $59 mask. I used some crude stuff that worked perfectly. Moates chip adapter socket, burn 2 chip burner, and chips with Turner pro rt. It worked wonders and I used it mainly for a boosted turbo v6. The $59 mask is where its at. I used a electronic boost controler, wideband, etc its all on there. I still have a flash drive of all the tunes I used over about 6 years of turbo v6 days along with the hardware incase I get the time to do it again on a different car.

I do have a terminator x on my turbo ls now. I love holley efi. About anyone can tune with it, very easy stuff. But if you can manage to use a 7730 ecm with a harness for it, it would probably be alot cheaper to do over the term x or dominator.

I don't get on here enough but I'll be following the thread.

Last edited by fasteddi; Feb 28, 2026 at 05:30 PM.
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Old Mar 1, 2026 | 07:37 AM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

When I looked into tunning the stock ecm or adding a later GM module and wiring, for a map and wide band o2 there was a lot of splicing and hacking involved. Plus, the tunning software looked complicated compared to the Holley. I called a few tunning shops, and they said they did not know how to tune the old ecms but could with the Holley on their dynos. With the Holley system I can leave the old harness in and go back to stock without a problem. I like the cost of the Terminator x and if it will work with the v6 I would rather use that it is $1000.00 cheaper. Besides if I ever wanted to swap to a LS engine, I could use it on that. My sensors are all compatible with the Terminator x I would only have to get a map sensor, and the harness for the stock distributor.
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Old Mar 1, 2026 | 11:53 AM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Originally Posted by dana0330
I am thinking about the Holley because it is the only one that can do 6 cylinders. I am doing all the work myself, I did get tunning software and a chip emulator, but it is way over my head. Plus they do not run a wide band o2 and no map sensor. I am not planning on running tat may inputs or outputs. The X should be all I need,
Pretty much EVERY aftermarket ECU will run a V6, among many other cylinder counts.

So really you have a multitude of options.

Regardless of what ECU/ECM you choose there will be some amount of wiring and ?splicing? involved. There is no V6 harness for the Holley ECUs available as an off the shelf option, so you will have to make your own harness or modify an existing harness, or splice into the OE wiring, just like you would if you simply updated to a newer GM ECM. So this aspect is a wash regardless of the ECU/ACM you end up with.

Like FastEddi, I've also used the '7730/'7749 with Code 59 ( AKA "$59"), and had great success with it on my turbo I6, yes, I6, I put it on my Nissan L28 (2.8L), and abused that combination for about 8 years, before replacing that engine with a 3.5L V6 from a 2006 G6, and continued to use the same ECM for about a year before going to an aftermarket ECU (Megasquirt), because I wanted more adjustability and more functionality in that car in particular, because I plan to push it way farther than most people would, otherwise, I would've likely stayed with the GM ECM. I also wanted more hands on experience with more ECUs so that I can better understand them and be able to tune them for other people, since I was getting into tuning engines for other people before then and I was getting asked about more aftermarket ECUs.

A Holley ECU will work to run your engine, for sure, but is far from the only option. The interface is pretty simple, which is both good and bad. It's good that it helps streamline accessing tables and settings that need adjustment, however, it also hides or makes it difficult to make some adjustments to really fine tune some aspects, that will either not be able to or need to use advanced tables that is really not that easy to use, and you really have to know what you're doing to use them effectively. I've been tuning Holley for several years and still find more ways to utilize the advanced tables. For most people though, the basic available adjustments are good enough, I'm just always chasing perfection.

As said above, regardless of what system you go with, the curve to learning to tune is steep, and will vary slightly based on the system you start with. Whether starting with OE or aftermarket system is easy is debatable, some aspects will be easier to start with an OE system, other aspects will be easier with an aftermarket system. If you plan to have someone else tune it, talk to the tuner you plan to use BEFORE you purchase anything. I've seen far too many people buy a system because the price was good, or had some cool new whiz-bang feature, but then couldn't find anyone locally to tune it. I've helped several people remotely in this situation, I don't tune their engine for them, but I help them get their engines up and running, and help guide them into initial tuning so that they can confidently tune themselves.

I tune mostly V8s, since I live in an area with a lot of domestic cars and most of the people I hang around are into domestics, however, I have personally used or tuned 6 cylinders engines with GM OE EMS, Megasquirt, ECUMaster, AEM, and have helped with a Haltech and do have a 6 cylinder car coming to me shortly with a Haltech, and I know many others like FuelTech, MAXXECU, and many others also are fully capable of running 6 cylinder engines. I only mention this because I have seen far too many people get tunnel vision on one ECU because their initial exposure was that that ECU was the "only" one that could do what they needed and either ended up spending more money than they needed to, found out that the ECU was actually more limiting than it was thought to be or not able to tune it well and no one locally able to help.
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Old Mar 5, 2026 | 06:43 PM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Does anyone know if the V6 is a odd or even fire ignition system?
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Old Mar 5, 2026 | 07:19 PM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Also how may degrees for the distributor cap to fire?
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Old Mar 5, 2026 | 10:47 PM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

It's a 60 degree bank angle V6 so it is even fire. Cylinders 1 & 2, 3 & 4, and 5 & 6 share a common crank pin on the crankshaft that is not offset (split pin). The firing order is 1, 2, 3, 4, 5, 6.

Looking down on the distributor cap from above like in the diagram below starting at terminal #1 and rotating clockwise back to terminal #1 is 360 degrees divided by 6 cylinders = 60 degrees since it is an even fire V6. It's 60 degrees between spark plug terminals on the distributor cap.

Since the camshaft rotates at 1/2 speed of the crankshaft it takes 720 degrees of crankshaft rotation to equal 360 degrees of distributor rotation and the engine fires every 120 degrees of crankshaft rotation with the distributor firing every 60 degrees of distributor rotation.




An old school Buick 3.8L V6 is 90 degrees because it started life as a 90 degree V8 that had two of the inner cylinders removed. Up through 1977 it had a crankshaft with a common pin. It was an odd fire V6 and it had an odd spacing on the distributor cap. 1978 Buick made the 3.8L V6 even fire with a split pin crankshaft and the distributor cap had an even spacing of 60 degrees. I might be a year off when the change happened. Was either 77/78 or 78/79.

A Chevy 4.3 90 degree V6 is similar but I think they started off with a split pin crankshaft and were even fire. Some race versions of the Chevy 90 degree V6 were odd fire because a common pin crankshaft is stronger than a split pin crankshaft.

Last edited by Airwolfe; Mar 6, 2026 at 08:10 AM. Reason: To correct an error I made.
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Old Mar 6, 2026 | 02:21 AM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Originally Posted by Airwolfe
It's a 60 degree V6 so it is even fire. Cylinders 1 & 2, 3 & 4, and 5 & 6 share a common crank pin on the crankshaft that is not offset (split pin). The firing order is 1, 2, 3, 4, 5, 6.

360 degrees divided by 6 = 60 degrees. So the engine fires every 60 degrees of rotation. It's 60 degrees between spark plug terminals on the distributor cap.

An old school Buick 3.8L V6 is 90 degrees because it started life as a 90 degree V8 that had two of the inner cylinder removed. Up through 1977 it had a crankshaft with a common pin. It was an odd fire V6 and it had an odd spacing on the distributor cap. 1978 Buick made the 3.8L V6 even fire with a split pin crankshaft and the distributor cap had an even spacing of 60 degrees. I might be a year off when the change happened. Was either 77/78 or 78/79.

A Chevy 4.3 90 degree V6 is similar but I think they started off with a split pin crankshaft and were even fire. Some race versions of the Chevy 90 degree V6 were odd fire because a common pin crankshaft is stronger than a split pin crankshaft.

Your math is just a tad off...

4 stroke engines require 2 full crank revolutions for a complete cycle, so 720 degrees, which ends up with 120 degrees of crank rotation between cylinder events.
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Old Mar 6, 2026 | 07:21 AM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Thanks for the info Airwolf. Six-shooter said that it is 120 degrees per cylinder firing event, but it is 60 degrees between each cylinder, is that correct?
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Old Mar 6, 2026 | 07:32 AM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Originally Posted by dana0330
Thanks for the info Airwolf. Six-shooter said that it is 120 degrees per cylinder firing event, but it is 60 degrees between each cylinder, is that correct?
I just edited my reply above. I hope I got it correct.

I just woke up from a sound sleep to my 81 year old step father (with Parkinson's) screaming bloody murder. He has weird dreams sometimes. I looked at the security monitor to check the cam to make sure he wasn't actually being stabbed to death in his bedroom. He wasn't. I just went down to check on him and fix him a drink. He's a mouth breather when he sleeps and gets dry mouth. Then I realized I was about to bust and went to take a leak. Fixed warm, steaming hot washrag to clean my eyes out and wash my face.

I'm just now having my first ice cold Cherry RC cola and Marlboro Red cigarette. My brain might not be 100% online yet.

NOTE: I may end up editing my above reply #19 a few times in case I got something wrong, explained it as clear as mud, or for spelling & grammar mistakes that stick out like a sore thumb.

Last edited by Airwolfe; Mar 6, 2026 at 08:08 AM. Reason: Spelling & Grammar
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Old Mar 6, 2026 | 08:28 AM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Originally Posted by Six_Shooter
Your math is just a tad off...

4 stroke engines require 2 full crank revolutions for a complete cycle, so 720 degrees, which ends up with 120 degrees of crank rotation between cylinder events.
Thanks for pointing that out. I had it right in my head but smooshed things together typing it out. I hope I got it right when I edited my reply and didn't make things as clear as mud. If I got something wrong or could explain it better please point it out to me.

Thanks.
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Old Mar 7, 2026 | 08:24 AM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Originally Posted by dana0330
Six-shooter said that it is 120 degrees per cylinder firing event, but it is 60 degrees between each cylinder, is that correct?
The engine crankshaft makes two full rotations (720°) to complete a full combustion cycle (intake, compression, power, exhaust strokes). There are 6 cylinders in play, so the cylinder firing (spark) events are 120° apart (720 / 6 = 120). The Holley software always talks in terms of crankshaft degrees.

The distributor is driven by the camshaft, and the camshaft runs at half speed from the crankshaft. So that would be 60° in terms of camshaft (or distributor) rotation.

Not to be confused with the term "60° V6". This 60° is referring to the geometry of the engine block, specifically the angle between the lefft bank and right bank cylinder centerlines as laid out in the engine block. It has no part in this discussion, does not matter.
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Old Mar 7, 2026 | 09:14 AM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

I do understand that the 60 degree is the geometry of the cylinders left to right and the degrees between the cap terminals could also be about 60 degrees. I was only asking about both so I could give someone at Holley the info to see what system will work for my engine. I want to thank you guys for the info. I am going to go with the Terminator X system all the connectors on it will plug into my sensors. I will have to modify a few things, but it will work. I did have to get a top plenum from a latter v6 because the throttle position sensor and IAC motor will work with the Holley harness.
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Old Mar 30, 2026 | 04:25 PM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Ok, I am installing a FI TECH throttle body fuel injection on my 91 3.1 V6 that came with factory injection. I added a Paxton blower for a little extra kick. I had a shop convert it over to Accel DFI and it never ran right, and that was back in 91. So, off with the injection and on to the throttle body injection being force fed by the blower. One question that I have is about the factor distributor. FI Tech says I need a HEI distributor with a magnetic pick up that puts out a sine wave. I could not find any specific tech on the factory distributor. Anybody know the output of this distributor? Thanks in advance.
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Old Mar 31, 2026 | 06:42 AM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Originally Posted by jumpinjakflash
Ok, I am installing a FI TECH throttle body fuel injection on my 91 3.1 V6 that came with factory injection. I added a Paxton blower for a little extra kick. I had a shop convert it over to Accel DFI and it never ran right, and that was back in 91. So, off with the injection and on to the throttle body injection being force fed by the blower. One question that I have is about the factor distributor. FI Tech says I need a HEI distributor with a magnetic pick up that puts out a sine wave. I could not find any specific tech on the factory distributor. Anybody know the output of this distributor? Thanks in advance.
The 3.1 does indeed have an HEI style distributor with a magnetic pickup from factory, with the pickup outputting a sine wave. It's basically just a V8/ TPI distributor with a 6 point pickup instead of an 8 point (and different oil pump gear drives and shafts and whatnot, but the electronics are functionally the same by 91).

I wish you all the best with FI Tech, the couple of accounts I've heard from friends with FI Tech haven't been super positive... don't reckon I've seen anyone convert an MPFI motor to TBI in all the reading I've done on the 60degs over the last 9 years, but there's a first time for everything.
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Old Apr 2, 2026 | 12:45 AM
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Originally Posted by LLCooLM495
The 3.1 does indeed have an HEI style distributor with a magnetic pickup from factory, with the pickup outputting a sine wave. It's basically just a V8/ TPI distributor with a 6 point pickup instead of an 8 point (and different oil pump gear drives and shafts and whatnot, but the electronics are functionally the same by 91).

I wish you all the best with FI Tech, the couple of accounts I've heard from friends with FI Tech haven't been super positive... don't reckon I've seen anyone convert an MPFI motor to TBI in all the reading I've done on the 60degs over the last 9 years, but there's a first time for everything.
OK, I am open to suggestions. I started this project in 91, took the 3.1 and 700r4 out of a totaled 91 Camaro and did the following: Arias pistons, custom ground cam by Crower to all the specs I gave, lots of head work, enlarged throttle body, O ringed the deck, copper head gaskets, Paxton blower and here is where this project went south. Now, this is back in 91 mind you. I had a local speed shop convert to aacel DFI which back then was a DOS based program, and it ran, but not well. And as what happens to a lot of projects, this got sidelined as my job had me traipsing around the globe and of course kids.And hopefully I do not get any flak on, as I have been a Chevy guy from day one, but this motor is residing in a 1971 MGB. I still have the original intake, and I did find the ECU and fuel rail, but I know of no one to do any tuning, and of course, tech has gotten so much better in the last 25 years. So, the long block has great bones, its the fuel management that has me stumped. So, if I had to start with a clean sheet of paper, any suggestions?
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Old Apr 2, 2026 | 06:24 AM
  #29  
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Originally Posted by jumpinjakflash
OK, I am open to suggestions. I started this project in 91, took the 3.1 and 700r4 out of a totaled 91 Camaro and did the following: Arias pistons, custom ground cam by Crower to all the specs I gave, lots of head work, enlarged throttle body, O ringed the deck, copper head gaskets, Paxton blower and here is where this project went south. Now, this is back in 91 mind you. I had a local speed shop convert to aacel DFI which back then was a DOS based program, and it ran, but not well. And as what happens to a lot of projects, this got sidelined as my job had me traipsing around the globe and of course kids.And hopefully I do not get any flak on, as I have been a Chevy guy from day one, but this motor is residing in a 1971 MGB. I still have the original intake, and I did find the ECU and fuel rail, but I know of no one to do any tuning, and of course, tech has gotten so much better in the last 25 years. So, the long block has great bones, its the fuel management that has me stumped. So, if I had to start with a clean sheet of paper, any suggestions?
Definitely no hate for having it in an MGB, I know MG folks love their GM 60degs. Their forums have helped me out a fair bit over the years too as far as where to go with the engine management, if you don't want to get into flashing chips and all, I've heard a lot of good things about Megasquirt ECUs. Can't really speak on the Accell DFI, not familiar with that setup, but if you want to stay away from using a distributor, the easiest route would be to convert it to DIS (distributorless ignition). DIS came on the 3.4L 4thgens, as well as most of the FWD 60degs; it's a popular swap, and necessary for folks to run when converting to the 3x00 FWD aluminum heads due to the intake, so there's a fair bit of support for it. In the pins at the top of the V6 forum here, you can find a thread called "Hybrid guide (fasteddis setup)", and it has a post detailing the swap. Basically, you just match up the wires between the plugs on the stock 3.1 distributor and the wires for the DIS ignition coil assembly, then add a crank position sensor. Going back to the MG folks actually, there's a site called BritishCarConversions that sells a kit for adding a crank triggering system to a 60deg block, basically just a notched damper and a bracket for a sensor. With this kit, if you were to use a stock ECU, all you'd have to do to get it running right on DIS is to change the base spark timing to 60deg in the tune, based off where the crank sensor mounts; if you have a half decent junkyard near you, and you want to go DIS over the stock dizzy (or the accel setup), I'd recommend pulling the ignition control module and wiring pigtails/ coils/ oil pump drive shaft out of something like a 2001 Impala or Grand Am, though the system did come on many many GM cars between '93 and around 2005 (probably totally wrong on the last year, but it was around for awhile). I know there's a guide out there for running DIS on a Megasquirt as well, Megasquirt has supported 60degs well for going on 2 decades now. The stock distributor will work normally with a Megasquirt as well.

Sorry for rambling, I tend to do that when I talk about anything 60degV6 related

Last edited by LLCooLM495; Apr 2, 2026 at 06:56 AM. Reason: added links
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Old Apr 2, 2026 | 09:55 AM
  #30  
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Originally Posted by LLCooLM495
Definitely no hate for having it in an MGB, I know MG folks love their GM 60degs. Their forums have helped me out a fair bit over the years too as far as where to go with the engine management, if you don't want to get into flashing chips and all, I've heard a lot of good things about Megasquirt ECUs. Can't really speak on the Accell DFI, not familiar with that setup, but if you want to stay away from using a distributor, the easiest route would be to convert it to DIS (distributorless ignition). DIS came on the 3.4L 4thgens, as well as most of the FWD 60degs; it's a popular swap, and necessary for folks to run when converting to the 3x00 FWD aluminum heads due to the intake, so there's a fair bit of support for it. In the pins at the top of the V6 forum here, you can find a thread called "Hybrid guide (fasteddis setup)", and it has a post detailing the swap. Basically, you just match up the wires between the plugs on the stock 3.1 distributor and the wires for the DIS ignition coil assembly, then add a crank position sensor. Going back to the MG folks actually, there's a site called BritishCarConversions that sells a kit for adding a crank triggering system to a 60deg block, basically just a notched damper and a bracket for a sensor. With this kit, if you were to use a stock ECU, all you'd have to do to get it running right on DIS is to change the base spark timing to 60deg in the tune, based off where the crank sensor mounts; if you have a half decent junkyard near you, and you want to go DIS over the stock dizzy (or the accel setup), I'd recommend pulling the ignition control module and wiring pigtails/ coils/ oil pump drive shaft out of something like a 2001 Impala or Grand Am, though the system did come on many many GM cars between '93 and around 2005 (probably totally wrong on the last year, but it was around for awhile). I know there's a guide out there for running DIS on a Megasquirt as well, Megasquirt has supported 60degs well for going on 2 decades now. The stock distributor will work normally with a Megasquirt as well.

Sorry for rambling, I tend to do that when I talk about anything 60degV6 related
Your "rambling" was very helpful for me and one of my future swaps, converting from dizzy to DIS.
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Old Apr 2, 2026 | 10:11 AM
  #31  
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Originally Posted by 86blackiroc
Your "rambling" was very helpful for me and one of my future swaps, converting from dizzy to DIS.
Glad to be of service! Just dug through some old emails to get a couple more links for ya... this is the guide from Megasquirt for running DIS on their ECUs, pretty good technical info for the trigger system. I also came across this section of FastEddi's original build thread. They discuss getting DIS working starting around post #838 on page 17, from the late great RBob. Looks like I misremembered slightly, the initial spark reference angle for the external crank setup will be 70deg, not 60. Could be different depending on how the trigger is mounted and all, but definitely worth the read if you're interested in DIS
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Old Apr 12, 2026 | 09:40 AM
  #32  
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Re: Holley Terminator x or Hp EFi for 6 cylinder

I just wanted to update the progress. I got the Holley Terminator x kit and was able to get it to work. It is not 100% yet I am still fine tuning it. I am running 17lbs injectors that I got from South Bay they are not listed in the Holley list. Should I get a set of Holley injectors that they list? and how may pound injectors should I get for I supercharged engine? I do not know how high I should go.
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Old Apr 12, 2026 | 07:00 PM
  #33  
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Re: Holley Terminator x or Hp EFi for 6 cylinder

Just put in the deadtime information for the injectors you have.
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Old Apr 15, 2026 | 07:41 PM
  #34  
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Re: Holley Terminator x or Hp EFi for 6 cylinder

I don't know what the dead time is for the injectors and how to find it.
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Old Apr 16, 2026 | 09:32 PM
  #35  
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Re: Holley Terminator x or Hp EFi for 6 cylinder

South Bay publishes their dead time information, you can also contact them.
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Old Today | 02:47 PM
  #36  
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Re: Holley Terminator x or Hp EFi for 6 cylinder

I asked them they did not have it. I should be able to get it from the numbers off the injectors.
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