Talk me into or out of Holley Terminator X

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67_Slimer

Real Hot Rods don't shift themselves.
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OK , I'm a very old school car guy. Refuse to put an overdrive , still rocking my 4 speed with 4.56's , Love my Quick Fuel 750 race carb so much but my buddy who is also old school was telling me about that Holley Terminator X setup. I researched on it last night and was very impressed ( not to mention it looks like a bad *** carburetor too ). OK I obviously know the basic pros and cons but with a decent built 340 that I have. Can I use my same intake and plastic fuel cell? Are there SIGNIFICANT power gains? Obviously need a new pump and filter but basically , I'm looking to be talked into or out of this by my fellow FABO friends.....GO!!
 
OK , I'm a very old school car guy. Refuse to put an overdrive , still rocking my 4 speed with 4.56's , Love my Quick Fuel 750 race carb so much but my buddy who is also old school was telling me about that Holley Terminator X setup. I researched on it last night and was very impressed ( not to mention it looks like a bad *** carburetor too ). OK I obviously know the basic pros and cons but with a decent built 340 that I have. Can I use my same intake and plastic fuel cell? Are there SIGNIFICANT power gains? Obviously need a new pump and filter but basically , I'm looking to be talked into or out of this by my fellow FABO friends.....GO!!
You may want to look into the Edelbrock VRS carb series. Both the 750 & 850 have annular boosters. Though it resembles a Holley carb, Edelbrock completely redesigned how this carb works. I've watched several videos on how it performs both on the street and track.
 
I just did the full deal Sniper deal and I love it (but, I wish I would have gone Terminator X). Power gains aside, I like that the car can sit for 3 months and I can touch the key and it fires, high idles until warm. I can drive it dead cold like a modern car. Tuning come from a lap top so not more pulling the distributor and f'ing with spring and slots, pulling the carb and trying these jets, this shooter, that pump cam, and getting to deal with spilling fuel.

But, it all depends on what you want and are used to tuning. Some don't mind dealing with the above and if your all dialed in then HP gains may not be something you get.
 
If you have a correctly SIZED and correctly TUNED carb, there are no substantial power gains between efi and a carb. having said that, I had EFI on the Dart. Mine was cobbled together from parts. I started with an old Commander 950, which is a 4bbl TBI, then later upgraded the computer to an Holley HP.
 
In my opinion the single most "Simple" > yielding great results for the mopar engines is the Mopar HEI conversion with the high powered OEM available E-coils powered by 1 wire full 12 volts supply.

Instant starts, super clean burning spark plugs, quick throttle response.

The 12 volt powered E-coil is the magic, the mopar HEI distributor just triggers it.

Starts like they have fuel injection > instant touch of the key, and yes carbureted.

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At a later test, dropped an Edelbrock AVS 2 650 cfm with the Annular Boosters on to this stock build 340 cam 360 engine.

Was a perfect match to displacement, fast throttle response. Just set the idle, and that was it.

I love to experiment myself. Always an opportunity to learn something new.

321 Go.....


☆☆☆☆☆
 
In my opinion the single most "Simple" > yielding great results for the mopar engines is the Mopar HEI conversion with the high powered OEM available E-coils powered by 1 wire full 12 volts supply.

Instant starts, super clean buring spark plugs, quick throttle response.

The 12 volt powered E-coil is the magic, the mopar HEI distributor just triggers it.

Starts like they have fuel injection > instant touch of the key, and yes carbureted.

View attachment 1716349858

View attachment 1716349860

View attachment 1716349862

View attachment 1716349863

At a later test dropped an Edelbrock AVS 2 650 cfm with the Annular Boosters on to this stock build 340 cam 360 engine.

Was a perfect match to displacement, fast throttle response. Just set the idle, and that was it.

I love to experiment myself. Always an opportunity to learn something new.

321 Go.....


☆☆☆☆☆
I have an electric pump , mine starts first try no matter the temperature or how long it has been sitting , but that's not the issue. I'm talking about the efficiency and tuning ease.
 
If you love your 750 so much, why mess with it? Not trying to start ****, just not understanding why. Unless it's a just because you CAN CAN CAN!!!, deal.
 
A throttle body style EFI has the same shortcomings of a carburetor. If your going EFI, the best route is multi port.
Again , it's more so the self adjusting features more than anything else that are making me have interest in this. So the similar performance or working operation isn't the issue.
 
If you love your 750 so much, why mess with it? Not trying to start ****, just not understanding why. Unless it's a just because you CAN CAN CAN!!!, deal.
Like I previously stated , Love my 750 , but the self learning adjusting of the Terminator was a huge point of interest.
 
A throttle body style EFI has the same shortcomings of a carburetor. If your going EFI, the best route is multi port.
You are over extending. A TBI system can be MUCH better than a carb. Once you learn to tune them, you are not screwing around with gassy hands, fuel dripping from opening up the carb, and "where in hell is the jet box?"

You fire up the computer and change the tuning.

TBI EFI pretty much solves carb like vapor lock/ fuel boil as long as the pump is set up right. Drivability is the main reason I went with EFI.



TBI is a great budget alternative if you don't want to spend more money on injectors/ manifold/ manifold mods. The only real difference, in hardware, between the TBI I use and port is just that. The Holley HP I have uses the same computer.

One last thing about EFI. Flow sizing is not nearly as critical as with a carb, especially a double pumper. You don't have to worry about "vacuum signal" as with a carb.
 
OK , I'm a very old school car guy. Refuse to put an overdrive , still rocking my 4 speed with 4.56's , Love my Quick Fuel 750 race carb so much but my buddy who is also old school was telling me about that Holley Terminator X setup. I researched on it last night and was very impressed ( not to mention it looks like a bad *** carburetor too ). OK I obviously know the basic pros and cons but with a decent built 340 that I have. Can I use my same intake and plastic fuel cell? Are there SIGNIFICANT power gains? Obviously need a new pump and filter but basically , I'm looking to be talked into or out of this by my fellow FABO friends.....GO!!
EFI is great in many ways. Rich at FastmanEFI is the guy you should talk to regarding the pros and cons of each system. He also tunes remotely. Great guy to work with, very experienced and informative plus gives great deals on all Holley's stuff. I used him on my conversions. He's also an extremely knowledgeable Mopar Guru.

 
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A properly tuned carburetor will make more power than efi because of the latent heat of vaporization of the fuel. If you make more power with efi it’s because your carb tune was off. That being said, if you don’t want to mess with it a self learning (that’s a myth really they don’t self tune they look at feedback and pick from a different table) tbi style of efi is just fine for most people. Port efi has much much, more capability and tuning options than TBI and ultimately is a better set up but you may not need all the extra features. Most of the problems with any of the efi systems come down to user installation issues (not following directions) or RFI problems which Holley has addressed by moving the ecu to the side of the throttle body. Both systems will need dedicated high pressure fuel systems (return style is always better) and if you can use your current plastic tank or not is up to you to research since you didn’t provide pictures or part numbers.
 
You are over extending. A TBI system can be MUCH better than a carb. Once you learn to tune them, you are not screwing around with gassy hands, fuel dripping from opening up the carb, and "where in hell is the jet box?"

You fire up the computer and change the tuning.

TBI EFI pretty much solves carb like vapor lock/ fuel boil as long as the pump is set up right. Drivability is the main reason I went with EFI.



TBI is a great budget alternative if you don't want to spend more money on injectors/ manifold/ manifold mods. The only real difference, in hardware, between the TBI I use and port is just that. The Holley HP I have uses the same computer.

One last thing about EFI. Flow sizing is not nearly as critical as with a carb, especially a double pumper. You don't have to worry about "vacuum signal" as with a carb.
Your exaggerating what I said. I said the tbi systems have the same shortcomings as a carburetor. What I mean by that, is wet flow. Not concerned about dirty hands and all the other gibberish. And a novice will spend a BUNCH more time learning to tune with those systems.
 
Nope , the price is too much for the reward to me. $2,000 I'd rather have in my bank account and I haven't seen a single answer that makes that worth it.

Just from what I have seen and heard because I have been watching the subject for years.
They cost quite a bit.
They very often never actually run right.
They often don’t last a long time. (Failure rate)


I spent that money on AC. :D
 
One of the main reasons I went with EFI is to get rid of the gasoline smell. The smell wasn't when driving (I had the carb dialed in), it was after parking the car in the garage for a few days. The smell would eventually soak into the garage and the car's interior. Then I would drive it and my clothes would pick up the smell, so that made me drive the car less.

The car is now better in every possible way, except for one: it lost a little piece of it's soul, or maybe I should say its personality. There's something about knowing just how many pumps the pedal needs on a cold start, or hearing the sound of the throttle blades going wide open, or having the interior smell like "old car". Like dialing a rotary phone or adjusting the rabbit ears on the TV, the new way is much better, but the old way had personality. If you count yourself on old school car guy, then I would not try to sell you on EFI.
 
One of the main reasons I went with EFI is to get rid of the gasoline smell. The smell wasn't when driving (I had the carb dialed in), it was after parking the car in the garage for a few days. The smell would eventually soak into the garage and the car's interior. Then I would drive it and my clothes would pick up the smell, so that made me drive the car less.

The car is now better in every possible way, except for one: it lost a little piece of it's soul, or maybe I should say its personality. There's something about knowing just how many pumps the pedal needs on a cold start, or hearing the sound of the throttle blades going wide open, or having the interior smell like "old car". Like dialing a rotary phone or adjusting the rabbit ears on the TV, the new way is much better, but the old way had personality. If you count yourself on old school car guy, then I would not try to sell you on EFI.
My garage has that distinct fuel smell and to be honest , wouldn't want it any other way lol. I have an electric fuel pump so no matter how cold or how long it sits , it always fires on the first try. I posted this for the reason of either getting talked into or out of and I think all the factors including the $2,000 plus figure , I'll stick with my carb. Thank you to everyone who commented along the way!!
 
Just from what I have seen and heard because I have been watching the subject for years.
They cost quite a bit.
They very often never actually run right.
They often don’t last a long time. (Failure rate)


I spent that money on AC. :D

All 3 of those points are totally valid. I would also add the question of parts availability. e.g. just exactly what throttle position sensor (or any other component) does my aftermarket EFI system use? Can I get it from the auto parts store today, or tomorrow at the latest?

All 3 of those reasons you said plus the one I mentioned is why I used a cheat code to get cheap, perfectly tuned, reliable, and servicable MPFI: EFI Magnum swap. Grab a 5.9, wiring harness, and computer from a 90's Ram (or B van, in my case), and drop it in the old A body using the factory EFI. Yeah, it has its limitations, and there's no instruction manual or tech support you can call, so it's not for everyone. Definitely not for the OP since he already has a decent 340. But it's perfect for me.
 
Again , it's more so the self adjusting features more than anything else that are making me have interest in this. So the similar performance or working operation isn't the issue.

I've never seen one "self adjust" worth a ****.

You can fix what you have, but I'm not typing out the how. If you read Vizard about carbs you'll be screwed up.

I suggest you scour FABO for posts by @Mattax and then see if he can hook you up with some links to the stuff "Tuner" has posted. Read all than and then maybe get the Obert book (I think its "Carburetors and Carburation) and when you get through that you can get the two volume set of Taylors books. I forget the title of those books.
 
The first time you get stuck and can't figure out what's wrong, you'll consider going back to a carb. Happened to me and I felt so helpless especially when the car was on the flatbed truck going back home. Aftermarket EFI has not been perfected like the Factory EFI.
 
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