I'm building a 400 with the Dart SHP block and AFR210 heads. I am quite keen on putting an EFI system on it. I've looked at Atomic, FAST, Holley etc and I quite like the features of the Holley Avenger. I see that Holley are bringing out a Terminator system with the injectors below the throttle blades. Does anyone have any comments to make about the likely differences between the two systems? Is it worth waiting for the Terminator?

Thanks for any insights.

 

I put a highly ported stealth ram on one and it runs great. You just have to get a different fuel regulator since the factory regs are junk and port the $#!& out of it.

 

Doesnt matter what system you use but depending on your power goals and cam size, the intake manifold can make all the difference.

I would avoid a tbi style or system that has injectors below throttle opening. (Unless it also has port efi injectors and can control both, switching to port efi for driveability and shower type for wot)

I like single planes ported to 1206 to match heads for big inch motors. Let them breathe

 

That's interesting Orr, Holley seems to have shifted the injectors to below the throttle blades on their new Terminator setup. I was wondering what the pros/cons were of that.

 

That system kinda looks similar to FAST ez efi systems and i bet holley designed this because of FAST systems. I dont like those kind of systems which basically are tbi style. They just dont make big power in that configuration.

Now its been tested that injectors mounted farther away from the valve, higher up on the runner can make more wot power, much like a carb system, as long as injector phase timing is correct. Problem is with lower air speeds at part throttle there seems to be driveability issues. Bad distribution of air and fuel. Terrible manners and absolutely a bear to tune. I read posts by a efi tuner at the engine master challenge and he shared those results. They destroyed one motor trying to figure it all out. .

Port efi closer to valve seems to be the best compromise for good power but good driveability. These systems are proven to work and make the most sense for a strong street motor. If you cam that motor right its capable of 575-600 hp and that exceeds most tbi style systems ratings.

The best setup would be a very complex system combining both styles. Japanese sport bikes kinda do this with some port injectors and some shower type injectors mounted way high on the runners. I even seen some individual runner intake setups used in F1 type racing that have injectors mounted before the throttle blades like a nitrous wet nozzle kit!

So you just need to find what you are comfortable with and capable of tuning. Lots of those systems are near 2 grand but the holley hp series seems best bang for buck around 1400-1500. It has some self tuning capability which really does come in handy, atleast setting up base tune.
Any of those systems can work with any port efi intake. May favorites now seem to be single plane efi intakes with 90 deg elbows and ls style round throttle bodies. The elbow however needs to be smooth radius bend to avoid too much flow loss. A cowl hood can really help in that area but you can fit a basic 90 under stock hoods

 

Thanks for your comments, certainly a lot to consider.

 

I noticed the Nascar guys have there injectors mounted rather high on there intakes.

 

That's correct, as per Orr's post. Moving them up the runner increases wot hp.

Good info Orr, I'm not much of a fan on the TBI stuff either. And mounting the injectors south of the throttle blades is a recipe for poor low speed running. I talked to them about that at the latest PRI. Their answer was that their new software will help make it run better. However it doesn't have anymore transient tables than before, so not sure how that will make a difference as that's the only thing that will really help that.

Cosmic, looks like you're not cutting any corners on your build, not sure why you would go with a TBI system. Imo opinion a multiport, maybe with the injectors moved further up the runner if that last bit of hp is that important to you, will give you the best overall power and drivability, hands down.

Thanks

 

Yeah I'm leaning towards the multiport now. All the TBI systems seem to run out at about 600HP. It doesn't give much room for improvement. Anyone got suggestions for a good multiport setup?

 

I would like to know what the nascar guys are using. Including the fuel pump, regulator, ECM, Injectors and size, intake, throttle body etc. They turn 9000RPM and 900HP.

 

I know some of it,

ECM is made by McLaren
Throttle body is made by Holley to Nascar spec
Most intakes started life at Edelbrock and are modified at the teams' facilities.
And I know the injector size is on the lower side of what is necessary. They increase pump pressure to compensate, that will typically give you the best results.

 

For the intake style with the injectors just below the blades you will also shell out more money for injectors. Does anyone know if the throttle bodies flow as much air when they have the injectors squirting away right below? I'm figuring all tests were done "dry." Just grab a used single plane setup or the proform/professional products efi setup.

 

I would go with MiniRam and use EZ-EFI multi port system. The mini on my 406 made outstanding power. With the EZ system, you will need to run a conventional distributor.

 

I believe the single planes have better air distribution and flow more air. The throttle bodies available for them can flow more as well.

 

If you are going to the trouble of a multiport system it would be better to go to full timing control don't you think?

 

The EZ is a lower cost management system. If you have the bucs, a complete system is the way to go.