Sniper EFI Quadrajet
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Drifting
Joined: Jul 2002
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From: The only Corvettes in Highett Victoria
Sniper EFI Quadrajet
G'day. I've been reading about the Holley Qjet Sniper EFI unit and have had correspondence with Holley about it regarding the use of the factory dual plane manifold. Holley say that a single plane is preferred but that some of their customers have said that it works on a dual plane OK. Then I thought I'd better come to the source of all good info. So, has anyone out there put a Sniper, either square or spread bore, on a dual plane manifold, and what was the result? I look forward to the discussion on this. Almost forgot, it all has to fit under the stock bonnet.
Regards from Down Under.
aussiejohn
Regards from Down Under.
aussiejohn
Last edited by aussiejohn; Nov 6, 2018 at 09:58 AM.
Pro
Joined: Jan 2016
Posts: 502
Likes: 103
From: Reno Nevada
The only issue with a single/dual plane manifold with the sniper or terminator throttle bodies is the fact that a single plane manifold gives the throttle body a signal across the entire bottom of the body and a dual plane does not. The Sniper/Terminator only have a single inlet on the bottom for signal.
A dual plane generally has a plate that splits the dual planes and as such will only give the throttle body signal for 1/2 of the engine. The RPM Air Gap does have a small space between the 2 sides so many have had luck with that. Worse case, some have milled out some of the center plate to offer signal to the throttle body from both sides of the engine with success.
If you just want something to bolt on directly, go with a single plane. If you want to mess with it and try to fit it under the hood, try the RPM Air Gap or similar dual plane as long as it has some way to offer signal across the entire engine.
A dual plane generally has a plate that splits the dual planes and as such will only give the throttle body signal for 1/2 of the engine. The RPM Air Gap does have a small space between the 2 sides so many have had luck with that. Worse case, some have milled out some of the center plate to offer signal to the throttle body from both sides of the engine with success.
If you just want something to bolt on directly, go with a single plane. If you want to mess with it and try to fit it under the hood, try the RPM Air Gap or similar dual plane as long as it has some way to offer signal across the entire engine.
Is my vette stock?? HAHA
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Hotrods Engine Masters show on motortrend has had issues with the dual plane and EFI. I would look at low profile single plane. Edelbrock Victor Jr has a low profile intake available
Racer
Joined: Nov 2011
Posts: 285
Likes: 36
From: Cedar Park TX
Put the Sniper Square bore on an old Edelbrock performer manifold (dual plane solid devider). Had to spend the time to correctly set up the throttle blades and AFR at idle. Since then, no issues with drivability.
It's in a big block camaro with a 4 speed. Have driven it for 3400 miles so far.
It's in a big block camaro with a 4 speed. Have driven it for 3400 miles so far.
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Joined: Jan 2000
Posts: 12,399
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From: San Jose CA
The only issue with a single/dual plane manifold with the sniper or terminator throttle bodies is the fact that a single plane manifold gives the throttle body a signal across the entire bottom of the body and a dual plane does not. The Sniper/Terminator only have a single inlet on the bottom for signal.
A dual plane generally has a plate that splits the dual planes and as such will only give the throttle body signal for 1/2 of the engine. The RPM Air Gap does have a small space between the 2 sides so many have had luck with that. Worse case, some have milled out some of the center plate to offer signal to the throttle body from both sides of the engine with success.
If you just want something to bolt on directly, go with a single plane. If you want to mess with it and try to fit it under the hood, try the RPM Air Gap or similar dual plane as long as it has some way to offer signal across the entire engine.
A dual plane generally has a plate that splits the dual planes and as such will only give the throttle body signal for 1/2 of the engine. The RPM Air Gap does have a small space between the 2 sides so many have had luck with that. Worse case, some have milled out some of the center plate to offer signal to the throttle body from both sides of the engine with success.
If you just want something to bolt on directly, go with a single plane. If you want to mess with it and try to fit it under the hood, try the RPM Air Gap or similar dual plane as long as it has some way to offer signal across the entire engine.
