Can someone explain Bridgeports vs Pro Max etc.

[Valero2.5]

i had a 2.4 EFI Bridgeport, wonderful motor, did 90 mph with four people and a cooler full, in my HST. and over a one foot chop. After the Demise of the Bridgeport, i know the 2.5 replaced it, what were these known as? and were they out for a few short years, i have brochures from Merc showing 2.4 Bridgeport EFI at 240 hp and the 2.5 EFI at 260 hp. What engine is most similar to the 2.5? was the Pro Max? or Pro XS? or neither, i am debating to refresh a 2.4 EFI Bridgeport power head i bought on here, vs get a different motor that already is ready to bolt on and go. I now run Valero Streams my Vee handles nicely with my 91' Merc 200 hp. balancing nicely on the pad around 80 mph with Hydraulic steering. i have many good props, from blueprinted Cleavers 3 and 4 blade from D.A.H. to Mazco's. and even an Allison cut Chopper. However my YT cannot seem to get a move on, or enough speed to lift, ( i think my HST raised up at about 68 mph?) with any motor i have run on it. I bought the MINT shape boat, with low hours (88') with a ridiculous 150 hp that went like 65 mph ( i now use that great starting motor on my Vee for tubing) and even with my low compression 200 hp ( 105-110 psi) i still could not get this boat above 68 mph??? i am seeking to get the YT in the 85-90 mph range with 3 friends who weigh 200 lbs each. My HST hit 97 mph with my 110 lb girlfriend with a Land n Sea Shift prop surfacing! until we threw a blade and i realized that was idiotic of me. I wanted a 2.5 i saw one for sale on here that i missed out on, What is difference between the Pro Max's and older 2.5's in say out of the hole etc. i know RPM's are much higher with the old 2.5's as with my Crazy high revving 2.4 EFI in the mid 7's. thanks, JIM

[pyro]

All original factory high-performance motors had the characteristic unpainted raw aluminum block and heads.

The 2.4 EFI Bridgeport was the high-performance 2.4L until the 2.5's came out. Nikasil block. 240hp at 7000 for EFI, 225hp for carbs.
The early high-performance 2.5's were 260hp EFI and 245hp carb. Nikasil.
Later, the 260 was replaced by the 280hp 2.5 EFI. Also Nikasil.

The 225 Promax was built during the entire 1990's period and a while beyond... A slightly under-rated 6800-rpm limited performance-minded steel-sleeved 2.5 with Laser style EFI, same intake used on the lower consumer EFI models, and 40-amp charging system.

There was also a 150 and 200 Promax, built as 15" motors for rigging on Allison boats. They were "improved" versions of the consumer motors, with synthetic reeds (instead of steel) and lightweight high-performance plastic cowlings.

[PaulR]

pyro...well said!!


The math says a 260 2.5 EFI only has 35 more HP than a 225 Promax but in the real world a 260 or 280 "feels" like it has double the HP! You said your goal is to run 85-90 with a full boat load, well your 2.4 BP horn motor might get you there with a big prop(30P cleaver)? A well set up YT with a 260 should run 105+ with one or two aboard. Put 10 to 12 inches of setback on it and run a cleaver!! If your boat hasn't been recored in the last 27 years it would be wise to inspect the hull before each use.

[Capt.Insane-o]

It's really tough to beat the friendliness of a 225 PM with some bolt on mods.

[madtunnel]

My unpainted 2.4 Bridgeport gave up its ghost a couple of weeks ago. Ran right at 90 turning 6800 to 7000 rpm with a 28 mazco 4 blade. I got my hands on a early model freash 225promax that still needs breaking in.All my guys tell me I am gonna be a lot happier with the 2.5. Better feul milage and more punch. Any guesses what I should see out of the promax.

[PaulR]

My unpainted 2.4 Bridgeport gave up its ghost a couple of weeks ago. Ran right at 90 turning 6800 to 7000 rpm with a 28 mazco 4 blade. I got my hands on a early model freash 225promax that still needs breaking in.All my guys tell me I am gonna be a lot happier with the 2.5. Better feul milage and more punch. Any guesses what I should see out of the promax.

This is perfect for the author of this thread. You can show us the difference between a 2.4 BP and 225 PM on the same boat as long as you run the same prop. I sure hope you hit the 6800rpm limiter, if not your boat will be slower, but like the Capt.Insane-o said, the Promax is going to be cheaper to run and to own but I don't think it will have more punch than a horn motor...maybe??

[madtunnel]

It will be after the first of the year before we make the swap. Do not want to hijack the man's thread but will let every one know what we end up with. It going on my 88 Allison XR2002 with 15 inch mid. At 1/4 below pad..I know I can get more out of it by going up. But I like being able to slow down with out the boat throwing me out.

[pyro]

The only reason the horn motor would have more punch is because it will likely be turning a smaller pitch prop. I'm sure the Promax would have more punch with the same tall prop on both motors, but you're missing the point of the horn motor if you're only propping it for 6800 RPM.

[madtunnel]

Velaros question was he wasn't sure of he wanted to refresh a 2.4 bp or go with another motor. I went with the New power head cause 1) the 2.4 stuff is getting hard to find and is dated. Also if you refreash the bridgeport you still are going to have trouble sooner or later. Its just the nature of those motors.

[pyro]

Mine ran great for 9 years before it finally tossed a ring locator pin after repeatedly making 8100 RPM passes on a 22p prop. I ran the piss out of it almost every trip out the entire time I owned it. The only thing I ever did to it was put a Brucato box on it and swap out a bad stator.

[madtunnel]

Am not knocking the motor at all. And was set to pull the trigger on mooba's long block he had on here for sale.Just saying in my case. For the money I would have to spend to fix mine. I can get a more reliable power head. The bridgeport is a good motor and full of power.But as a wise ol man told me one time. It's still a bridgeport..

[madtunnel]

Ok I didn't want to take over valero's thread but since it seems to have pettered out I will post an update. The bridgeport is removed and the 225 promax has been installed. As mentioned befor I still have to break this power head in. Once I do that I can start giveing some top end wot numbers. Also as mentioned befor I plan on running the same 28 mazco I ran on the boat befor. Looking forward to running the new power.

[pyro]

Moomba's longblock is sitting in my shop right now awaiting an electronics transplant and a set of one-piece heads if I can find some.

[madtunnel]

Congrats on getting that. From the pix he sent me that thing looked like new money. All your stuff gonna transfer over without any issues. Good luck with the swap.

[200valeroyt]

For whatever it's worth, my stock carbed bridgeport, 120lbs compression, ran 2 - 3 mph faster on my Viper verses a stock 1996 2.5 200. Same prop, BP pulled around 300 more rpm @ 7,500.