I know ICDEDPPL and it looks like kvogt are running crank trigger and coil on plug so there's more to the cost than just the EFI

dan spent a lot to make it perfect but works, it’s really about cost at the end of the day both can work well just a matter of money.

Eddie young makes an injector plate for 575s that can support a lot of power. He can tune your ecm as well. He’s probably done enough to get you really close with a tune he already has.

8-71 swapped 575s have been done and can make really good power. Like up to 900 if you lean on them. 800+ is typical

No reason not to do it this way when starting from a 575


https://www.offshoreonly.com/forums/...ml#post4417235

lots of people were taking their 575s once the manifold went bad and put on 871s, you could do that as well and switch to the holley system and be at a real reliable 800 with efi, and be in it for the cost of the blowers and system. then sell your 575 stuff to offset the cost.

Yes I was thinking that to I can order the 8-71s that’s not a problem I have my blowers sold already just don’t want to spend a extra 10k per moter on efi. I did talk to Eddie today. His is 2k per moter and he said about 1000 to tune and get it correct. So that’s about 3k a side. I’ll have to keep thinking. And figure out the most cost effective solution.

Check with Frank Ungarten, he goes by panther on here, he has a 36 apache and is doing the tuning on my boat.. he is very good with tuning EFI.

Thanks !!

https://cimg0.ibsrv.net/gimg/www.off...3b3afc0916.jpg

What was the total per moter for that set up ?

I would never go carbs again. Really when I went from car stuff to boating I didn`t understand why boaters are using 1970s tech but I got used to carbs and kinda like em now . nothing wrong with carbs but it`s old tech .

I ordered everything from Alex Haxby, it included tech support and a base tune.Alex is great guy and great to deal with.
The above will run about $8k. Fuel pumps and misc. a few bucks more ... on the high high end you`re at $10k . That`s going coil/plug which you don`t have to do.
$10k minus $3500 for my Daytona ignition, fuel pumps, quick fuel carbs . Thats $3250/ engine
$1500 in tuning
I`m not including the 7" screens or EFI mechanical gauges.
Throttle bodies I got are good for 600hp each , I have 2/engine. I think probably around 1000 hp is the limit as I`m running 85% duty cycle on the injectors@43psi. raising the fuel pressure will help that .

I`m making 973hp in full trim.

It is not plug and play does take some time figure out .
I had to move a few sensors that are in the throttle bodies down below the blower.
IAT and MAP come to mind.
The two IACs had to be rewired to operate in series.

Gas savings are significant .
No more soot on transom , no fouled out plugs.
Idle is excellent. Transition from idle to in gear was a ***** and took 2 days to get right , partly because my tuner is a car guy and it too time to figure it out . In the end it was all timing and limiting the learn feature below 1500rpm.
Guardian mode is what really nice.
You can set up all kinds of parameters , for example if water pressure falls below a certain pressure , or oil temp is too high .etc it will automatically limit rpm to 2500. (Don`t have to watch every gauge while running)
Might save an engine and then it`s worth every pennie.


Holley is always improving, they have this option also :

https://www.holley.com/products/fuel.../parts/550-531