2.5 Carb motor Pro max help

[drwarz]

What year did the Pro max 2.5 start? What is the difference between the 2.5 Pro max and the regular 2.5

[rock]

Ports, exhaust, intake, probably timing and compression. Other than that they are almost identical.

Rock

[Jim Speros]

And light weight cowling? Mid 90's sometime I think.

[FUJIMO]

...same gearcase?...

[Jim Speros]

OK, After more thought I find your question confusing. I looked up old brochures. In High Performance a carb model was always or nearly always available. In '84 and likely other years when the class Mod VP was carb there was a high compression, needing race fuel, carb model. In 88 there was a carb Bridgeport, pump gas, model available, When 2.5s were released in early nineties a carb model was available.
To ask about a carb Pro Max is a contradiction. ProMax is an EFI model. A promax induction or a single horn are the EFI types merc used.

[Jim Speros]

I am still thinking about it. I suppose I could go further. I mentioned that ProMax is a EFI model. Its really a general term or knickname for the production type injection too. It first appeared as Laser, XRi or Magnum lines. The early horn type injections were on high performance engines ; they utilized a boat mounted fuel pump. Eventually Merc released a high performance line of EFI's called ProMax that utilized the the same induction and allowed a simple rig with engine high pressure fuel system contained under the cowl.

Maybe I cleared up something?

[OnPad]

...same gearcase?...

Optional sportmaster gearcase.
What Rock and Jim said, plus solid mounts, non painted block, and higher rev limit. Production started about 1995.
Jim is correct, Promax was never produced with carbs.

[TEXAS20225]

pro max born in 1994 150 200 and 225 in dec 94 i saw one at a boat show in Dallas i went to then fishing world next day and bought the one at the show on a 20 Bullet it was sold by Key Puckett a well know racer also at that time there were only torqmaster and cle lower units sporty next year or so all efi with ecu twisting up to 6750 only seven petal front was 225 other 2 were 5 petal all unpainted i owned all of them thru the years as a motor rebuild shop i could run what ever i could afford so ive had everthing except the opti stuff from300x down and everything in between the fastest was the 280 by 3 mph over the 300x

[tlwjkw]

started like bobby says in '94 (sporty was out yet).. 150 and 200's were pretty much "naked" production EFI motors with some fancy "bolt on" twists.. tha 225 (probably tha most popular/dependable motor ever from high performance division) had tha seven petal front and a little different rod slot work.. all had ecu's that would let 'em turn up a little more than production motors.. jmo.

btw.. bobby still has his "original" BULLET.... .. knock off tha dust and it still looks like tha day he brought it home!!!

[rgsauger]

Bobby needs to take me crappie fishing!!!

[tlwjkw]

might be a chore.. he's gotten alot like me i think.... breakfast, ez chair Fox (naaaaap), lunch, ez chair Fox (naaaaap), supper, ez chair tha Five, naaaap, bedtime.. repeat... no time for anything else.............................

[David]

Some days I think Bass and Walleye Boat was the best magazine ever. And I don't fish. At any rate, the copyright violation is from August 1996 and the article describes the differences between the regular motors and the Promax's. Most sources say that the 225 PM came out in 1994. I had one with a 1993 serial number. The 225 PM came with a CLE initially. At some point the Sportmaster replaced the CLE.

[TEXAS20225]

ditto on the bass and walleye mag was the best publication ever i had every issue they told you a lot of real stuff i finally gave them to one of my son-in-laws. My motor was a 1995 model built in 94 im thinkin best i can(these days for sure) that the pmaxs were in production for a year before i saw one puckett talked me out of the cle said they did not work well on these Bullets so i got the torqmaster which i sent to JC's for a cone looking for mo speed LOL i got introduced to Tommy Warren(TLWJKW) not long after that he had 2003 with a 260 on it and a world of knowledge and a right nice guy to boot rest is history i was allready deep in rebuilding lower units for several years before he dropped the mota rebuilding bug in my life i never got over it oh and im done fishing i went one time last march and that was it for me

[Revenge22]

I am shocked the internals are the same! I guess its the fiber reeds and less restrictive intake that allows them to make power past 6000rpm, but still surprised. that should mean a ported 2.5 with a promax front-half should be just as reliable, correct?

[TEXAS20225]

150 promax was identical to 150 xri from what i saw except for the ecu same on the 200 ecus 200 xri again both engines used exact same internal part numbers in rotating assembly the 150 did not stick around long not to many people were intersted in them 200 how ever was pretty popular it also was one of the other blocks that had bleedline bibs in the block like for cabs the 225 did not have them i could blow your mind with this statement the the 200 and 225 has the exact same part number for the sleeves in the advance sleeve catalog the machine shop added rodslots and giant champhers on th porting to ehance the timeing as far as a restrctive intake im not sure what your referring to the promax used different reeds ive rebuilt lots of 200efi and tested a bunch on my bullet there are like kids they dont all perform the same most likely ecu difference a few ran very high 70's on the test boat