Which N/A efi motors?

[SummerObsession]

This subject has come up more than once among a few of us out here in the sticks.
If you were going to pick some naturally aspirated motors with efi, which ones would you use? It seems a lot of builders are offering products along these lines now.
A friend was just telling me about GT 588" efi motors making around 750hp, no reliability issues so far.
I would eventually like to convert my Peto 580" motors (most of the parts are the same or close) to something like these.
These are just a few engines I know of:
Sterling-750 n/a efi available
TMP-750-800hp efi
Zul-several diffent packages, don't know about efi
GT-750hp 588ci
Sonny's ( ) up to 813ci, efi on any of them
Anyone have any experience with these or others?

[Steamin' Rice]

Pfaff makes a nice 600HP and 700 HP EFI that is N/A.....

[SummerObsession]

I forgot Pfaff.
He builds great stuff from what I know...have not heard about his efi though.

[Whipped Caliber]

Pfaff's EFI stuff is great!! i have one of his 565ci Q-rotor EFI motors and it starts 1st time each time!!! 45 hours on it so far!!

[Havasu Cig]

I have been told that Pfaff is ahead of the curve when it comes to EFI motors.

[SummerObsession]

Thanks for the info guys.
Anyone know about GT?
I had someone recommend them, but I don't see much of his stuff out here.

[Charley]

J
Give those things back to Larry and give him a HP # to get.... Larry is awesome and will do it with out emptying yer wallet

[DogHouse]

You've got good parts in those motors. All you need is more compression and cam to get you up in the power range you're talking about. If you want to spend the $$$ on EFI, that's easy enough as well. Your Dart single plane manifolds can be converted for use with injectors very easily. From there you'd just need the throttle bodies, injectors, ECMs, high pressure fuel system (pumps, regulators, rails, etc) and other assorted EFI hardware (sensors, wiring, etc). Charley is right about Peto, great work, fair prices. He's not up to speed yet on EFI though. Wally (Heavy Hitter on the boards) helped set me up with the EFI hardware and we dyno'd and tuned at Larry's shop. If you step up your motors a little, you would be in the same ballpark as mine. If you want to run Electromotive EFI and direct fire distributorless ignition, you could start with my EFI program and tune from there.

[bigkatboat]

GT spends YOUR MONEY ON YOUR MOTOR! No hype, no BS, just good parts, the correct knowledge, and PURE RELIABLE POWER. He once ran a blown gas drag boat motor ALL season, with just a valve spring change. He won his class in IHBA that year! You can "buy a name" or you can "buy a motor", GT MARINE delivers, at realistic prices.

[SummerObsession]

You've got good parts in those motors. All you need is more compression and cam to get you up in the power range you're talking about. If you want to spend the $$$ on EFI, that's easy enough as well. Your Dart single plane manifolds can be converted for use with injectors very easily. From there you'd just need the throttle bodies, injectors, ECMs, high pressure fuel system (pumps, regulators, rails, etc) and other assorted EFI hardware (sensors, wiring, etc). Charley is right about Peto, great work, fair prices. He's not up to speed yet on EFI though. Wally (Heavy Hitter on the boards) helped set me up with the EFI hardware and we dyno'd and tuned at Larry's shop. If you step up your motors a little, you would be in the same ballpark as mine. If you want to run Electromotive EFI and direct fire distributorless ignition, you could start with my EFI program and tune from there.
Thanks for the offer! You're right about the parts. However, I do want to swap out the cranks. 4130 isn't always the SAME 4130 if you know what I mean. :wink: To get reliable horses, I would eliminate the weakest link. Everything else is top notch!
The reason for efi, IMHO, is NOT for power. Carbs will make just as much or MORE at WOT. Idling, dock manners, a clean transom, etc. etc. are the main drivers for me. I am looking into a program that would allow an easy change between 91 octane and 110 octane fuel as well. A little timing and a fuel curve change and it might run pretty well at the shootout and on other special occasions! :wink: