Not sure, no flame arrestors right now.

Kinsler is correct to a point. The stuff he is talking about is actually the easy part for anyone who knows what they are doing (10 minutes). Tuning it all once it's on the engine is the tough part, regardless of the system used (many hours on a dyno to do it right).

Adjusting the airflow port-to-port is also something that can only be done on the engine with proper equipment. I'm sure this system does have MAP, and Air temp sensors, except unlike a plenum throttled application, there is NO TRUE MAP SIGNAL. That is why port throttling works the way it does. In this setup the MAP sensor becomes a Baro sensor and isn't really used as the tuning parameter, throttle angle is, so it becomes a pridictive thing, not an actual calculation. Works great on racing engines, but less so on engines that see a variety of conditions.

O2 sensors can be put into boats for quick tunning, but not for use on a continuous basis. Even if they could be, O2 sensors are only used to correct slight errors in calibration, NOT as the calibration themselves. If you try to do that, you'll end up with an engine that runs, but runs very badly.

Again, it can be done, but if we were both setting up identical engines and I did it my way and you used Kinslers Port Throttles, we'd both end up with the same performance, but you'd pay a lot more money, and have a lot more hassels. And although you might think your engines ran great, if you compared them side to side with mine day in and day out mine would run better.

Oh yeah, and that's not even including things like Idle Air Control which would give me a consitant idle under any condition and is near impossible to duplicate with port throttles

Agreed, or if you want to make it look cool, and have money to spend, I'd look into some ASM manifolds. Have it polished and Chrome plated and maybe shorten the runners a little for your RPM.

bcarpman

Have you been down this road before? you appear to be speaking from experience. That is why I posed this query.

ASM? an anacronym or a manufacturer? These are Fords. I can provide single plenum or tunnel rams with injection bosses. My TRs are tall for more midrange power. would that follow suit with EFI? Short versions are available.

I have not done this on a boat, but I have worked with every conceivable type of FI on cars and motorcycles. I did a port throttled FI motorcycle years before almost anyone else.

Sorry ASM = Arizona Speed Marine. Didn't know you were doing fords. The best way to do FI if you've got a good carbed tunnel ram that works is to cut off the top and weld on a plenum with the throttle body on the front (or where ever it will fit) It's quick and easy and if you use a high enough capacity Throttle body, you'll make at least as much power as you did with the carbs. Don't underestimate the size of the plenum. When we were testing this at GM, we kept getting more power almost as big as we could go. However you will lose throttle response if the plenum is too big.

Choose your runner length just as you would with the carbs- longer equals lower torque peak. Shorter = more power up top. There are some basic equations that will get you close, but you're better off going off experience from the carbs. Nice thing about the FI will be a little better driveability down low, and better economy if it's tuned right. Also, if you're currently running carbs that are sized a little small to get you around the docks, you can run as big of a throttle body as you'd like and make more power.

Bottom Line: Choose a manifold that works for you now. Put FI bosses in it, and a plenum on top. Choose a TB that's big enough for the power you are making. Use the electronics that are recommended by whoever will do your tunning.

PS. If you do it right you can make a pretty cool looking plenum.