Power-Up, HT383 vs. Supercharger

[Hollywood]

Geeze I replaced my GT40 with an '09 PCM EX343 with an ACME 380 prop on my 2002 SAN, and I have no problem getting up to 50+ mph with RPM to spare.

cough*bull*****cough

[WakeSlayer]

Downhill?

[Mikeski]

Flipside,

My boat with the 330EX ran 47MPH with one person, a stripped tower, and a low fuel tank turning the 380 ACME. Unfortunately I like to wakeboard with a decent size wake and that takes weight. With 2k lbs of human, water, shot bags, and batteries the boat does not have enough power to plane off turning the 380. I can tell you firsthand that it's quite embarrassing having to drop the handle because your boat cannot pull you out of the water. This has happened to me on several occasions and I don't want it to happen again. Put your bimini up, put up some tower speakers, load the racks with wakeboards and you can start waving goodbye to that top end speed too.

Hang on to that prop, I might want to trade you my prop once I finish with my motor...

[Mikeski]

Pulled the MEFI out of my boat last night. Good news, it's the fully adjustable 4b. As I understand, this is the most desirable MEFI version.

[Miljack]

Mike,
I didn't realize there were "subversions" of the MEFI controllers. How does one determine the difference between a 4 & a 4b? By adjustable, does that mean the "programing" is not password protected?

I did a little browsing on this, and there are a few EFI systems that are totally tunable, a couple of the drag racers here posted links, you could probably get enough $$ from the sale of your complete EX330 to get you a good stroker and new EFI system.

Will you have to design your own interface for the gauges and other systems on your boat?

[Mikeski]

Miljack,

My boat is an SE, the only gauges I need to consider are the tach, oil pressure and temperature, I believe all are wired directly to the motor sensors, not the MEFI. I would guess the motor sensors on the LE/TE boats are wired to the gauge controller, not the MEFI so that should not matter either. The MEFI motors are plug and play.

One motor builder I have talked to said that the PCM programs are not tunable, you need to wipe the MEFI and start from scratch. His quotes includes dyno time for dialing in the MEFI, maybe water time too if needed. He has provided me with two options, both would be turnkey plug-n-play. Option 1 is a 383 build up based on my current block and heads, he said he can beef up the lower end to make up for the 2 bold deficiencies. Option 2 is a 406 cubic inch build based on a new Dart small block. Believe it or not both options are less expensive than the supercharger. The 406 build would likely have significantly more HP and torque than the stock big blocks, the 383 would be pretty close to a stock big block (by big block I mean Python, not ZR6). Both builds will have significantly more torque in the 2000-4000 range than anything currently available from Nautique. He is in Arizona, I would need to freight or drive my motor to him for the buildup.

Still considering other options. Talking to Tim Morgan, the local builder, on Monday.

[2gofaster]

Yes, if you have an SE your gauges are wired direct to the engine sensors.

My thought is this............ you are well within the parameters of the 2 bolt block with your goal. You're not turning high rpm, you're not doing elevated rpm for 2 hours at a time, and your hp/torque goals aren't out of this world. If you were wanting to make 600hp+ then I'd definitely want the aftermarket block.

[bmh2208]

I'd say go with the option 2, only knowing that if you anything of a gearhead, your gonna want more power down the road and the 406 as the base will give you more to work with later on. 600hp or bust!

[Miljack]

Mike,
do you mind sharing which builder you are speaking with who has experience with the PCM version of the MEFI? You can PM or email the info to me.
The "shop" I sent my MEFI to reprogram has a great deal of experience with the Ramjet "crate" engines from GM, but his program wouldn't operate the fuel pump. I probably could have worked through it with him, but it would have taken several round trips of my MEFI to Socal to accomplish.

I'm just trying to get the fuel curve closer than what PCM had to use for a production engine.

[Mikeski]

www.larrysengine.com

[Miljack]

Mike,
Thanks for the engine builder contact. You mentioned that you were going to dual exhaust with your new engine setup, will you also go with the larger down pipe into the water? Reason I'm asking is that my boat is dual exhaust, and FAE supplied a 4" diameter down pipe, and I would assume that with duals and the higher output engine you would also want this size.
On my boat, I noticed the last time that I took a slalom set, the "rooster tail" has moved back, and is also still there closer to the boat. Does that make sense? In other words, the "rooster tail" used to be about 4' long and about 15' off on my boat, it now seems like it's 5' or so off, but it looks 10' long. I was only skiing 32 that day.

You may want to ask Larry if some of his customers with the larger down pipe have noticed this, may not be a problem for your boat/hull.

[Mikeski]

Not sure if Larry will do what I want with the FAE? I am wanting to have 4" mandrel bent 90's that Y together into the down pipe, not T together mitered 90s like most of his. I also plan to have 4" pipes made for the inside of the boat too. Basically need to find a shop that fabs diesel exhaust. This stuff should be commonplace around a shop that does diesels. I think the wake should not change much if I keep it in the propwash and keep the exhaust downspout narrow.

[Mikeski]

2gofaster,

Sorry I never replied to your post. Lots of wakeboarders in my area have experienced catastrophic failures with their stock motors. Once we get them propped down so they will come out of the hole they spin right up to the rev-limiter if you are not careful. I think a motor with a beefier bottom end is the long term solution for my needs. Running around at 4200rpms while slalom skiing and 5100rpms while barefooting seems to be pushing things from my perspective. It's not like I am just running a quarter mile, my motor is getting hours at these rpm levels. Remember, I am running a V-drive, it's a whole different ball game from a direct drive. There is a big difference between 1.23 and 1.46 final drive ratios.

[Miljack]

Mike,
I saw a picture on his site of a 226 (older version) with dual exhaust for which he built a system like you described. I think the main issue will be going from a 3" down pipe to a 4" pipe.

I was going to pull mine and try a few slalom sets without the FAE, I'll let you know if there's a difference.

[Miljack]

Took a slalom set today with the FAE removed, and I think that the wake was a bit softer without it. Same speed and rope length as last set with the FAE, but water conditions were quite different.