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Discussion Starter #1
If you are converting a dual dominator manifold over to EFI and you are going to use 2X 4-barrel throttle bodies and wanted to run an IAC would you just run the IAC in one of the two throttle bodies, both, or none at all?

Also, would 1600CFM per throttle body (3200CFM total) be plenty of air? I know you can't really compare carbs to EFI but if you where running 2X 1250's before and went to 2X 1600 there should be plenty of room.. right?
 

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How big is the engine? Some engines require more IAC, so teeing both of them might need to happen.
 

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I just converted my 632 14 degree headed nitrous combo to Holley EFI and used 2 Accufab 2000+ cfm throttle bodies!
Not using an IAC, I haven't fired it up yet..... Any day though!!

 

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632 BBC 12 deg head

Electrically can most of the EFI units handle running both IAC motors?
The Holley can drive two GM/Chrysler steppers. Most race cars don't run an IAC. Personally I would, I don't see a downside. Just makes it run better when cold started, can help it run better in gear, allows it to not have the throttle plates jacked as far open in general.

If your units truly flow 1600 each, that should be good IMO.
 

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Discussion Starter #6
I just converted my 632 14 degree headed nitrous combo to Holley EFI and used 2 Accufab 2000+ cfm throttle bodies!
Not using an IAC, I haven't fired it up yet..... Any day though!!

Looks really nice!
Are the injectors really high on the runner? Most of the ones I have seen have the injector down closer to the intake port.
 

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Discussion Starter #7
The Holley can drive two GM/Chrysler steppers. Most race cars don't run an IAC. Personally I would, I don't see a downside. Just makes it run better when cold started, can help it run better in gear, allows it to not have the throttle plates jacked as far open in general.

If your units truly flow 1600 each, that should be good IMO.
Cold starts would be the main goal of an IAC. Also to help keep the RPM up while setting the break. I'm sure I can get away without them but just curious if 1 would work or not.

They are "listed" as 1600cfm. Is there a calculation for how much air you really need? Seems like people using single blade throttle bodies are getting away with less than 3200cfm?
 

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I usualy place the injectors as high as possible for best atomization. Also I am not a fan of iac motors I have always been abale to do what I need in aplpha n with temp correction curves. Also I think the 1600 throttle bodies will do you just fine. Good luck.

KG
 

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Looks really nice!
Are the injectors really high on the runner? Most of the ones I have seen have the injector down closer to the intake port.
This seems to how alot are getting done, I now from testing, and running this same manifold that Monte prefers them high up the runner....
He is the one that did all the plumbing, and had the EFI conversion done.
 
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