IDF or IDA Efi choices

[Chris]

Howdi all,

So it’s time for me to start making purchases for my intake setup and I just can’t seem to find something that exactly suits my needs.
So I have two directions I can go.

My engine:
402ci 9.2 deck
Dry sump
Cnc 225 trick flow high ports
Custom cam (circa 260/260 .650 @0.050)

Idea is to be able to Rev to 7500 without it nosing over and intake flow being a restriction. Car is a 95% street car.
I’m not shooting for all out power, drivability is key however the engine will easily be 6-650hp.
I will have to run an 8.2 deck intake with spacers due to there not being a manifold to suit.

Borla only offer 50mm for their 8.2 (their other option of 58mm is too large I feel anyway).

Efi hardware do have some nice 55-53-50 tapered TB’s but they only offer an IDF manifold for the 302 block. Of which they can do a 52mm TB over the listed 50mm. The IDF annoyingly doesn’t look as good in my eyes but that’s not a deal breaker. They have said 600hp on 50mm is not a problem.



Soooo after that essay - which would you choose and why?
IDF or IDA?

Billet PRO-RACE IDA 52/50/48 or 55/53/50 Tapered Bore Throttle Body

Billet IDA Tapered Bore Throttle bodies, Available in 2 Sizes. Tapered Bore Throttle bodies typically flow 5% more then a Parallel bore. 55/53/50 - 55mm at ram tube face, 53mm across the butterfly & 50mm at the manifold face. or 52/50/47 - 52mm at ram tube face, 50mm across the butterfly &...

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PRO-STREET throttle body IDF type 2 50mm

*** Now Manufactured From Billet not Cast ** Type 2 IDF with reverse mount injector for inboard injector mounting for improved throttle response and idle control on V8 applications.

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Pro-Series Ford 289/302 Windsor Quad IDF (2) V8 stack injection

This Windsor V8 Stack Injection 289/302 Quad IDF Pro-Street Throttle body kit.This kit is now available for the Ford 289 - 302 Windsor motors. Kit includes manifold, studs and nuts, assembled throttle bodies, linkages, ram tubes, fuel rail kit with -6 or -8 AN ends. **Note Black Ceramic coating...

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[Randy V]

……
Custom cam (circa 260/260 .650 @0.050)

………. Car is a 95% street car.
I’m not shooting for all out power, drivability is key however the engine will easily be 6-650hp.
…….
…….

2 things come to mind….
1) I think you chose the wrong cam profile for a “street” car & “drivability” …
2) I think your choice to go with EFI instead of carbs is a good one, because you’d have a heckuva time getting and keeping Webers working on the street with a wild cam profile.…

 

[Chris]

2 things come to mind….
1) I think you chose the wrong cam profile for a “street” car & “drivability” …
2) I think your choice to go with EFI instead of carbs is a good one, because you’d have a heckuva time getting and keeping Webers working on the street with a wild cam profile.…

The cam and valvetrain has been specced in accordance to it being a street car, although its got decent duration and lift its not wild in my books personally. Have spoken to many cam companies etc regarding my goals and all came back with similar specs - so i hope its ok , the LSA is 112 and sensible ramp rates have been chosen for the lobe profiles with longevity and street use in mind. This will remove a chunk of the aggressiveness, whilst the cubic inches will also make the cam behave better than running it on something like a 331/347 etc where it would be questionable driveability wise.

Im not expecting it to behave like a toyota yaris, its still a hunk of a v8 churning out a chunk of power but i dont anticipate it to be a dog to drive. I know of a guy with a 650hp 427 pantera on an extremely similar topend setup that behaves beautifully on the street.

Yeah carbs would've been a total nightmare with it thats for sure

 

[JP Verweij]

Carbs with the correct chokes will do fine with this engine. Thats why you can change chokes, to make up for the loss of vacuum and create more vacuum.
All about carb basics.
EFI is just a bandage for those who don't understand carbs.
EFI can end up in a nightmare if you dont know anything about VE tables, AFR target tables and how both are working toghether.
Carb tuning is just jets & chokes, and synchronise one a year.
EFI is mathematics. You calculate what the ECU will do. The ECU will only do, what you tell him to do. It does nothing on its own.
8 stack EFI needs to be synchonised also, at start and like carbs every year. Like motorcycles.

 

[Chris]

Carbs with the correct chokes will do fine with this engine. Thats why you can change chokes, to make up for the loss of vacuum and create more vacuum.
All about carb basics.
EFI is just a bandage for those who don't understand carbs.
EFI can end up in a nightmare if you dont know anything about VE tables, AFR target tables and how both are working toghether.
Carb tuning is just jets & chokes, and synchronise one a year.
EFI is mathematics. You calculate what the ECU will do. The ECU will only do, what you tell him to do. It does nothing on its own.
8 stack EFI needs to be synchonised also, at start and like carbs every year. Like motorcycles.

I feel we have digressed from the idea of this thread haha.
I have no concerns about my future efi tune, I’ll be running DBW, traction control, multiple maps, knock protection, more precise and stable timing, temperature and pressures protection and flex fuel, don’t think carbs would give me that as an option


What I’m more interested in at the moment is advantages/disadvantages with IDF vs IDA and TB sizes.

 

[Davidmgbv8]

.650 @.050 sounds a bit aggressive even on a 112. My thought is what transaxle are you going to use to put that power down?

 

[Chris]

.650 @.050 sounds a bit aggressive even on a 112. My thought is what transaxle are you going to use to put that power down?

Basically every option ticked at CMS shortened G50/50

 

[Jim B.]

Chris, I saw your username of GTR_Garner, is this going in a RCR GT-R?

 

[Chris]

Chris, I saw your username of GTR_Garner, is this going in a RCR GT-R?

Hey,

No it isn’t I’m afraid, username is related to my last couple of toys were r33 Gtr’s.