Holley Sniper XFlow - Chevelle Tech
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post #1 of 11 (permalink) Old Sep 4th, 19, 2:10 PM Thread Starter
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Ron
 
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Holley Sniper XFlow

https://www.holley.com/products/fuel.../parts/550-541

Finally make a unit with a 900 cfm body that is capable of 800 NA Hp. This is a 4 injector set up. They also have it in an 8 injector that is capable of 1375 boosted.

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post #2 of 11 (permalink) Old Sep 4th, 19, 2:37 PM
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Re: Holley Sniper XFlow

I've often wondered how they rate the 800 CFM at 650 HP and now the 900 CFM is rated at 800. Maybe a builder with experience can clear it up for me but I feel like an engine that makes 800 HP with a Dominator would be down a bunch of power with a 900 CFM carb. Am I off base here? Does it not apply somehow to EFI?

I know my 496 drops power if I take the 4781 (850) off and put a 4780 (800) on.

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post #3 of 11 (permalink) Old Sep 4th, 19, 9:45 PM
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Re: Holley Sniper XFlow

You get more injector with the XFlow as well. Four 120 Lb/hr injectors versus 100 lb. in the regular Sniper. Maybe the HP limitation is fuel related more than air?

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post #4 of 11 (permalink) Old Sep 5th, 19, 6:23 PM
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Re: Holley Sniper XFlow

I like the knew throttle body bores. I always wondered why the Sniper had such squared off bores, but I guess it was so they could launch a new product a couple years later.

I too have wondered about throttle body CFM vs rated HP as well. I can understand if it was a MPFI where the TB is dry flow (flows more air), but these are TBI and wet flow.

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post #5 of 11 (permalink) Old Sep 5th, 19, 6:39 PM
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Re: Holley Sniper XFlow

I've been hesitant to put the 800 CFM version on my 496 because of this despite that it's rated at more power than the engine made. Maybe the XFlow is the way to go. It's a little more expensive and requires an external regulator, though.

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post #6 of 11 (permalink) Old Sep 5th, 19, 9:10 PM
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Re: Holley Sniper XFlow

Quote:
Originally Posted by Tommy the Cat View Post
I've been hesitant to put the 800 CFM version on my 496 because of this despite that it's rated at more power than the engine made. Maybe the XFlow is the way to go. It's a little more expensive and requires an external regulator, though.
The external regulator is a plus in my book. You do hear about failed internal regulators on the Sniper.

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post #7 of 11 (permalink) Old Sep 5th, 19, 10:10 PM
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Re: Holley Sniper XFlow

Quote:
Originally Posted by Greg Owens View Post
The external regulator is a plus in my book. You do hear about failed internal regulators on the Sniper.
I admit I haven't done enough research and I didn't know that. Good to know.

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post #8 of 11 (permalink) Old Sep 5th, 19, 10:45 PM
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Re: Holley Sniper XFlow

Comparing it to the original Sniper, it's the same unit with a smoothed air horn on it. I'm sure the injectors are larger as advertised.

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post #9 of 11 (permalink) Old Sep 6th, 19, 12:29 AM
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Re: Holley Sniper XFlow

xflow is pretty much the same as sniper or super sniper except for 3 things. It is exactly the same wiring diagram and software!

there is some key wording changing here but essentially holley is saying the same thing.

external regulator, which you have the option to do this with sniper or super sniper
contoured entry for more flow, little irrelevant for forced induction applications
bigger injectors 120lbs vs 100lbs in sniper.

Honestly I am not sure why they made it good to 1300+ in forced induction applications, generally speaking at this power level you should really consider a MPFI setup for better control of such a high horsepower and high dollar motor.


I think this is a great product for those in NA applications up to 800hp and want a larger body. The super sniper at is only good for 700hp in NA.


Personally I still recommend sniper setups to anyone considering, it honestly changed my entire driving experience drastically only for the better.

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post #10 of 11 (permalink) Old Sep 6th, 19, 2:41 AM
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Re: Holley Sniper XFlow

Carburetors and EFI throttle bodies aren't apples to apples. Carburetors rely on the venturi effect to start the flow of fuel where EFI throttle bodies only flow air with the fuel added mechanically.Those 2 things effects both airflow and fuel flow so its not easy to compare the 2 different types of induction even though they both are similar (naturally aspirated).

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post #11 of 11 (permalink) Old Sep 6th, 19, 6:02 AM
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Re: Holley Sniper XFlow

Although I built and dyno'd my 572 with a Super Sniper, I feel that by the time I actually get to drive the car (hopefully by year end) it's going to be passe'. We got it to flow 882 cfm and the fuel curve stayed good all the way to the top, but it's close to maxed out. I'm not planning on running this all that hard, but I feel I'm on the edge with it. I don't know I would change to another TBI though, I will jump to MPI if I decide to switch. I'm just hoping this unit doesn't screw up at least for a while...
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