You might want to download the software and see what it tells you about Marine application.

Wanted to give Alex Haxby props for his great customer service regarding my conversion to a Holley MPFI for my 496 stroker build. He is well known for his expertise and talents in everything marine or automotive for that matter, but I gotta say, he takes the time on the phone to explain things, and he's patient with those of us who aren't fluent in "EFI"! I will get there. Very excited to get my new Holley system. I plan on running a D.U.I. EST style distributor, unless the holley DIS is worth the extra money. Will wait and see.

do you need to change the cam to use this efi unit?

I didn't and I have an agressive solid roller. It used to have stalling/docking problems with a pro systems dominator. Now it idles like my stock 496 mag used to.

Absolutely not. It's funny you ask because this build has evolved so many times since I first contacted Bob Madera last year. The final cam he cam up with was designed to run with my dry KE cast headers and originally, we were just going to use a carburetor. At the last minute I decided after researching and speaking to Alex Haxby, I was foolish to not pull the trigger on the new Holley MPFI. The cam bob made is pretty agressive (exactly what I wanted) and he has stated that the EFI will only benefit the idle characteristics of a cam like what is being employed in my build.

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Haxor - When are we going to see the completed projects? I saw a little something cool - definitely want to see more.

I've got a few on the HaxbySpeed Facebook page. It would be cool to see some from all the members here who have made the switch, or started from scratch on their EFI projects. Also, there are quite a few engine builders here that have been doing some cool stuff. I know MER has a few under his belt now, Brian41, BobL, Speed and Custom Marine in FL.
I think Orlandi was up 20hp from the dominator carb on his second pull with the EFI. It'd be cool to get some other feedback, comments, criticsms, etc. The more info is shared, the better it is for the community.

Alex,

How extensive are the Guardian/Engine Protection features ?

Bob

we have not gained any speed as of yet with minimal tuning on our homebuilt EFI but hope to get back on it soon...just tuff with not being able to get a 02 to live....