I understand, I believe the article was written for automobiles. Trying to answer my own original question and I have many more. This is what happens when the engine builder keeps the owner totally in the dark about his own build. I wasn't even allowed to attend a dyno session and got only a grainy vid and dyno sheets as proof of life. When I got it home I found untightened plugs in the injection ports in the intake manifold and carb base plate just as I left them when I delivered the parts. I asked specifically for pics with the oil pan off so I could verify my parts where used(Trust but Verify) never got one. Pics of rockers installed but avoided letting me see the lifters(Trust but Verify) I know what's supposed to be in there and will verify before this thing ever sees fire. The whole thing turned out to be a chitty deal and still pisses me off. Pulled a valve cover when I got it home and found that they where drilled and tapped for breathers and oil fill WHILE BOLTED ON MY NEW ENGINE. Didn't appear to be run like that but surely set me up to blow it up. Cleaned up the mess but will remove the oil pan and verify no debris and my parts among some other things. From what I see, beautiful professional job of assembly BUT...............I have questions including how it was set up .on the dyno. Crappy deal for me but I'll eventually get it sorted out. It's why I come here seeking knowledge.

Tyler Crockett`s numbers look good to me.

Optimum Air/Fuel Ratio for Supercharged Motors




12- 20psi as if there wasn`t much difference, lmao.

and 9:1 can run 8-14psi?


Whoever wrote that needs to put down the crack pipe and get some help.



Deep if you`re not allowed to be at the dyno that`s a HUGE red flag.
Try and keep me from seeing my own dyno , that`s not going to go work out for the engine builder .

I think someone should start a Dyno gone wrong thread, I'll bet there are plenty of stories out there similar to Sam's

Agreed. I was going to travel upstate NY and get a room the night before. Excuses why not to come up and then a phone call, hey your engine is done and made so so hp. WTF Still so pissed off by chit that happened in 2015 the engine went to the corner of the garage and I was really tempted to leave the sport. I trusted the WRONG people. I should have trusted myself to do the build. I let the boost scare me as this is a one shot deal for my poor azz. At 65yo I would like to run it up the lake a few times at trips and sell it. The price of an SCX alone may get me divorced. lol

So I have been running a M3 Procharger on 502s, small roller cam, carbed,. headers. WOT 9 LBs boost and 10.5 ish AFR. never had issues yet been 14 years now. static CR is 9.2
I think all engines are different with heads, cams, ign systems, boat weight, etc. so I don't believe much in the chart.

Thanks ICDEAD. Mr Horsepower "The majority of the engines we build are supercharged. A lot of builders like to run conservative A/F ratios, usually 12.0-12.5:1. I personally through our in house dyno tuning find that ratios of 12.9 (being the richest) and 13.3:1 will make more horsepower. The most important thing to remember when tuning for maximum horsepower, that will be reliable is that the boat has the correct fuel delivery system to supply the engine. Carb or EFI engines both need fuel curves which are ramped properly."

I couldn’t agree more. Every app/build is specific to the rule of thumb. Actually is no rule of thumb considering all the factors. JMO as always. Well maybe some good old school experience also. Then they introduced the chillers / coolers whatever you prefer to call them put a whole new factor in the mix. That’s a great thing but still…. We boat in so many different conditions/environments and builds. That’s what makes it so important to be build specific.

Build them right and do a cool tune and they’ll last. Don’t get greedy with power over 1 - 2 mph. Simple but yes can be expensive!!!
btw thumbs up to Apache on the video I posted from years ago. Bad a$$ engines there to withstand that kind of abuse. That’s running hard for any hardcore boater. At least me anyway. I love it. 💪🏽😎

12.5 , 12.9 - 13.3 might make the most power yes, but for how long? I just feel better running fat and lose a few HP then replacing engine internals

If i had known I would have went over to Jim Ford's for you I know the place and his dyno operator .