Originally Posted by MILD THUNDER

Agree. Mike Tkach on here has a pair of 588s with 8.3L whipples, and a pair of 1050 quick fuel carbs. They make 1200HP, and idle at 650 in gear. The bypass valve in the whipple is nice.

One nice thing about EFI though, it can be a big help for some of the guys running radical cams, combined with 18'' six blade props. A lot of times in order to get a carb'd setup not to fall on its face when shifted with big props, you really need to give them a lot of fuel and air. Which then becomes a problem of a fast neutral idle speed, or a rolling idle(surging), in order for them not to stall. Some builders have fought this problem, by adding shift solenoids, so that the throttle lever will be bumped up when put into gear. This eliminates that 1200RPM Nuetral, 700 in gear scenario when setup right. With EFI, the controller can take care of that.

Originally Posted by HaxbySpeed

Aside from being able to adjust and optimize your fuel curve for every load and rpm point, the biggest benefit to using a good efi system is that it manages the whole engine. You can program it to monitor every conceivable sensor and engine condition, and then tell it what you want it to do when a parameter is out of range; pull timing, reduce rpm, add fuel, etc. Total engine control, built in wide band control and monitoring, guardian system, knock protection, built in data logging, etc. really make the extra cost up front worth it. A good efi system is far more reliable then any carburetor, and will last much longer. Also, if you value your time, tuning an efi engine's fuel curve takes a fraction of the time it takes to dial in a carburetor throughout the whole rpm range.

Originally Posted by ratman

so you buddy wasn't running EGT temp sensors? i know i would on an engine set up like that...rm

Originally Posted by MILD THUNDER

I can attest to that. Dialing the fuel curve in on a carb setup IN the boat, is time consuming. There's more to it then just jet sizes. esp with twin carbs on twin engines.

I wanna say a while back I priced out a EFI system for a blown roots setup, and it was around 5k per engine? Does that sound in the ballpark?

Originally Posted by Griff

I've had both Carbs and EFI. Both have their plus's and minus's.
I've had carb engines flood the fuel bowls when lauching the bow high and pulling back on the sticks.
I've had some minor vapor lock issues with my MPI's in exteme hot humid weather.




I thought most of the marine EFI set ups used fixed curves for fuel mapping and do not self adjust because of the lack of O2 sensors????

Originally Posted by professor_speed

Take cost out the equation and the choice becomes clear. EFI wins everytime the only reason for carbs is cost plain and simple.(or rules if you are racing in class, but again thats to control cost) New EFI systems, like Holley, Fast ect. are not hard to use, they just cost more.

Originally Posted by kidturbo

My experience with those older TBI style setups, Holley or FASS, you could give it to me and I'd probably still trade for a good carb...

However one can easily hit the local bone yard and scavenge everything ya need to convert any marine engine to modern EFI for a little bit of nothing. With all the aftermarket ECM tuning options available today, I'd opt to build my own setups. Browse one of the LS forums and you'll find everything ya wanted to know about swaps. Big cams, blowers, turbos, all purr like a kitten when topped with modern fuel injection..