Procharging 500EFI's
 

Im thinking about adding prochargers to my 500EFI's next winter when i have them freshened, and wanted to know from someone that has done this about tuning reliability...im finding alot of info about whipples but not anything about prochargers on the 500efi motors...also who is good with tuning the MEFI-3 blower motors?
thanks, Kevin

Articfriends (mi) or Eddie young (TN)

I would switch to mefi4b's and I have been tuning them for a while.as for reliability,this 382 has been 115mph and never a efi/engine failure.
heres a fun little video of it running.

Guessing you don't tow any skiers ! Very nice !!

if it is in the budget concider the whipple,s,you will be much happier.

You know we're a dealer for both and there's pros and cons to both the Whipples you have to flash the Mefis and it's not the easiest way to tune real time which is one of the things I don't care for where the Procharger may not be as a complete system because of the electronics but you can use any engine management system and you can tune real time in the boat to get the most load cells and make it as user friendly as possible. They both have their place and they both make good power.
Here is two nice examples. The Whipple with the Mefi and the Procharger with our twist on AEM's Infinity.
Hey either way come see us a the Miami Boat Show booth F419 in the engine tent.


https://scontent-mia3-2.xx.fbcdn.net...a2&oe=5AF4C072

Small block with Whipple

Big Block with Procharger

https://scontent-mia3-2.xx.fbcdn.net...70&oe=5B1D08D2

why mefi4's over the 3's?

The 4-b has more tuning ability than the 3's.........Id go with the Whipple and the Holley HP or Daytona sensor box

When done correctly Prochargers are awesome! You are on the right track with freshing the engines first.

I loved my M3SC procharged 500efi's (2001 Baja 33' Outlaw 98+mph). Grand sport center installed everything when the boat was new. My friend Chris, the 3rd owner, is still enjoying it with over 320 trouble free hours, freshing top ends as prevention around 300. I had over 250hrs running hard, poker runs, etc. Before selling. I can't remember specifics but wanted to respond while on here. The fuel injectors, lines, filters and mounts, pressure regulators, pickup tubes, we're all upgraded. Ran about 7ish PSI. 30psi water pressure thru hull pickups. Engine oil or water never got hot even on long runs. I really can't say enough about a properly setup centrifugal supercharger. I think they get a bad name from how many people try to install them cheap, crank the boost up later without retuneing, way too much boost with blow thru carbs, and expecting a "bolt on" kit. Forcing air in is forcing air in, roots, screw, centrifugal, turbo, are all great done right.

Enjoy!

Tuning is the key !! ran a procharged setup for 5 years and loved it !! but really needs to be tuned with a 02 in my opinion...do NOT install like procharger instructions as their setup is close to pull and pray !!!

the fuel and spark compensation tables(boost) are very large and can really fine tune the running of the engine.
the hp500's that I tuned went thru 3 stages,stock tune fixed(mefi4b conversion) then 540's afr heads and cam change,,then last summer a bigger cam than the 1075 cams we were running.
all tuning done in the boat w/ o2's,,took 4hrs from the dock to 110mph blasts.went 115 but only held the o2 meter to say go,no go.:D
boat rips now,friend is very very happy.

10 years ago I bought a boat with a pair of Procharged 500 EFI's. No idea on tuning but they ran rich as hell and blackened the transom. I was told when I bought it the engines needed refresh so we soon pulled them, sold the Prochargers, and built 9.8 to 1 compression 540's with heads, cams, intake work.

Just as a side note. Might want to go on Youtube and hear the Prochargers on different applications. I know the newer heli-cut gears are quieter, but they make a lot of noise, IMHO. Particularly in a twin application. I sold mine and went turbos.

My M4 is much quieter than a Whipple... A little "rattly" sounding at idle but quiets down under load..:)

Video link... (may have to quote me to see it unless IB has fixed the issue)



WOO HOO ! the embedded video WORKS !!!

That's not bad! I had old school M1's and they were noisy! LOL!

Prochargers can make a ton of hp, fairly low parasitic drag. For years guys jacked up fuel pressure under boost vs actually tuning them. Now with all the high impedance, hi flow injectors you simply swap in larger injectors , set base fuel pressure then open up pw under boost (as far as tuning).
in old days guys ran them with stock tune, no stat, the ect table adding fuel until 140 but motor ran 100 so transom was black, oil was gassed ip, plugs fouled.
mefi4 would be nice but if you only plan on running 7.5 lbs boost or less and not trying to turn motor over 6000 a mefi3 has boost multiplier tables to 150 kpa. I've tuned mefi 3 blown boats that ran fine