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Which Holley EFI?

1967coronet440

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Alright I’m switching from my fitech set up to Holley, but I have one question. Which system do I use? Holley tech told me to use the terminator system which I might consider. But I like the stealth 4500 and and super sniper system better. Most (all) of you have way More knowledge than me about this so here’s my specs and let me know if more info is needed.

440/505

Victor max wedge heads (sending out to be ported)

Super victor intake
263/270 @.050
650/651 lift
11.9:1 cr
Plan on running 108-110 fuel

Estimated 700+hp

509B0A3B-10A9-4C0B-802E-F1562A01D16A.jpeg
 
/raises hand
I don't know more than you, and certainly don't know more about fuel injection retrofits. Curious to know though... why are you switching? And whats better about one over the others? Hopefully some folks with both good and bad experiences will indeed chime in. Did you have that stroker runnin on the FITech? It looks like a hummer.
 
No the fitech is brand new, theyre about equal units, both have the same features. I like the Holley tuning software better that’s the main reason why I’m making the switch.
 
Also I like holleys compatible gauges I’m thinking of doing my whole dash in their gauges or maybe the digital display.
 
The computer is the same whether it’s Terminator, Sniper or Super Sniper. The difference is the tb size for the Super Sniper.
 
I guess my question is, which is best for a 700hp application

Holleys descriptions are sort of vague when it comes to power ratings. Seems they go from 650max with the super sniper to 800 minimum with the stealth 4500. I’m stuck in the middle of those ratings
 
I don't think there would be a minimum, you can't just start an engine and expect to make 800 hp. Makes no sense.
The ratings usually come from the injector size and quantity of injectors. (how much fuel they can deliver)
If you are worried about being limited by the system, then get the larger one.
 
I don't think there would be a minimum, you can't just start an engine and expect to make 800 hp. Makes no sense.
The ratings usually come from the injector size and quantity of injectors. (how much fuel they can deliver)
If you are worried about being limited by the system, then get the larger one.
That’s what I thought, but Holley specifically says on their site “minimum 800hp” which is confusing
 
Well, let's look over the specifications.

Stealth 4500 - (8) 100/lb hr. injectors. 1,440 CFM throttle body.
4150 Super Sniper 1250 - (8) 100/lb hr. injectors. 800 CFM throttle body.

One has 2.125" throttle plates (Similar to a 1,250 CFM Holley Dominator) the other has 1.6875" (Similar to an 830 CFM Holley Carburetor). The linkage is not progressive. The 4150 series Sniper EFI may bring down the peak, (as shown by AndyF) 20-horsepower over a Dominator Carburetor on an engine making a true 730-HP, but what an engine dyno won't show us is the vast difference in drive-ability between the two.

A Holley Sniper EFI (base model) can handle a 700-HP application. Proven once again, by AndyF, I believe he said the Injector duty cycle was at 85% with 710-HP on his 470. Maybe he can chime in here.
 
Well, let's look over the specifications.

Stealth 4500 - (8) 100/lb hr. injectors. 1,440 CFM throttle body.
4150 Super Sniper 1250 - (8) 100/lb hr. injectors. 800 CFM throttle body.

One has 2.125" throttle plates (Similar to a 1,250 CFM Holley Dominator) the other has 1.6875" (Similar to an 830 CFM Holley Carburetor). The linkage is not progressive. The 4150 series Sniper EFI may bring down the peak, (as shown by AndyF) 20-horsepower over a Dominator Carburetor on an engine making a true 730-HP, but what an engine dyno won't show us is the vast difference in drive-ability between the two. A Holley Sniper EFI (base model) can handle a 700-HP application.
Holley tech advised against using the sniper, saying I would max out the injectors. Seemed like a default cover out *** answer. He said terminator would probably be the best option and from what I understand I can change out the injectors in the termi to handle the added power
 
Holley tech advised against using the sniper, saying I would max out the injectors. Seemed like a default cover out *** answer. He said terminator would probably be the best option and from what I understand I can change out the injectors in the termi to handle the added power

I agree, there is no reason to get involved with the Terminator series other than it comes with a middle-of-the-road throttle body @ 930 CFM.

I'm guessing he would recommend it however as the base terminator kit is over $2,000 and you would need to swap injectors prior to installation, looks like it comes with (4) 80 lb/hr @ 43 PSI injectors.
 
I agree, there is no reason to get involved with the Terminator series, I'm guessing he would recommend it as the base terminator kit is over $2,000 and you would need to swap injectors prior to installation.
Would you consider the 4500 for my application? I also have been looking at the super sniper 1250 but again the description is vague stating 700hp forced induction. To be completely honest the car won’t see the highway, around town cruisin to shows and what not and track time only. Drive ability isn’t my main concern. I want the best fit for my engine and not leave power on the table. 4.10 gear transbrake car. Thanks for the input I’m very green when it comes to this ****.
 
To give you a little more insight, the base Terminator comes with the (4) 80 lb/hr @ 43.5 Psi injectors.

Going off the https://fuelinjectorclinic.com/hp-calculator, that will support around 550-HP @ 85% injector duty cycle.

Holley Sniper, with (4) 100 lb/hr @ 58.5 injectors, same calculator, 789-HP @ 85% injector duty cycle.

I believe AndyF said he was at 85% duty cycle making 710-HP on the Dyno with the Sniper EFI. ---- At 7000 RPM the Sniper was running at 85% duty cycle and was using about 350 lbs/hour of fuel. The fuel pressure held pretty steady at 62 to 64 psi. We have a Holley 12-1200 fuel pump on the dyno, which didn't have any issue keeping up with the Sniper. ---
 
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Would you consider the 4500 for my application? I also have been looking at the super sniper 1250 but again the description is vague stating 700hp forced induction. To be completely honest the car won’t see the highway, around town cruisin to shows and what not and track time only. Drive ability isn’t my main concern. I want the best fit for my engine and not leave power on the table. 4.10 gear transbrake car. Thanks for the input I’m very green when it comes to this ****.

Stealth 4500 seems ideal (if you're truly going to make near 800-HP). If you would run a 1,250 Holley Dominator Carburetor than there isn't that much difference.
 
Hadn’t had the engine on the dyno but it should be close to the 800 mark, and for future upgrades I don’t plan on making the car slower lol. Eventually I’d like to get an aftermarket block and take it to the next level
 
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