Hi all. . . might be a dumb question, thought I knew the answer until a marine place kept asking for all this additional information. have a 2005 280, want to pull that powerhead off, and get a 225 promax or 225x powerhead on it instead. Shouldn't they bolt right up, or am I missing something? Thanks again for advice, i'm lacking some knowledge in this area.
280 motor replace with 225 powerhead?
- Thread starter flying07
- Start date
h2oskiier30
Well-Known Member
You may have to change out a couple of studs due to different length requirements on the one piece plate vs the two piece plate. Also, I'd suggest taking a look at John Marles' cooling mods for steel motors on one piece plates page.
http://www.us1.cc/racingcoolingsystem.html
http://www.us1.cc/racingcoolingsystem.html
fnshrmaster
Active Member
Just did it, studs are different length, motor mounts will use different bolts. Are you keeping the one piece adapter or going with a two piece? Depending on your climate, I would keep the factory cooling system, especially if you have cold water.
thanks for the info. i do plan on using a two piece adapter, then i can keep the thermostats, correct? I'm in MN, water temps might hit mid 70's at warmest, usually cooler. What length studs did you get, or cut them or? Longer or shorter block bolts? Thanks for the info everyone!! Now to find a 225. . . that's proving hard . . .
whipper
Well-Known Member
A 05 280 is a nice motor and I would just run that on your GS. You'll want the 280 power eventually after the learning curve Ill bet.:big grin Makes no difference learning with a 225 or a 280 you'll need less trim with a 280 at 90 than a 225 so probably even safer at higher speeds or as safe as higher speeds are.:shock: One things for sure if you are bent on starting with the 225 KEEP the 280 power head for later. My guess is it will end up on there and you wont have to buy one because you already have one. Once you start adding a 3rd and 4th passenger with a 225 its like really I wish i had a 280 or 260.:razz
A 225 is fine and seems like alot at first untill you reach top speed.:big grin
A 225 is fine and seems like alot at first untill you reach top speed.:big grin
h2oskiier30
Well-Known Member
If/when you find a ProMax, if it has been run on a two piece plate, it should already have the correct length studs in it.
Thanks everyone for the words of advice. Now i'm really debating what to do on the swap! don't know that i have the cash to keep a 280 lying around, but i see the point in doing so. though i plan on the boat doing more 'boating' then just flat out running, who knows what it may become in the future. . . what to do what to do . . . .
njj502
Active Member
Oh I dunno...I thought 103 was pretty good for a 225..... :soap box :wink
whipper
Well-Known Member
haha ya ya you and two others is 23 years. If I had a promax like yours there would be no need for anything else. BUT Can yours do 103 with 4 in the boat? got ya on that one.:beer:
There is absolutely nothing wrong with a 225 promax thats for sure! Its probably one of the best all time motors ever made on any Allison. if you want triple digits its just going to be a whole lot safer and easier with a 260/280 with 260 electronics thats all. 90-97 with a good strong promax setup right light load on most any GS at close to sea level with a 28-30 pitch 3 blade prop with the very odd super sweet 4 blade in some cases. I say that because I think Todd did 98 with his 28 TX4 when the 225 promax was hanging off the back. theres lots of props that work well on the GS also. Some of my favorites over the years have been in no order, 26 Off shore,28 drag4,27 ally cut Trophy,30 Chopper11,29 Spinelli,28 Ally cut SRX,25 Trophy stock,28 Drag3. The 28 drag3 and 25 Trophy have had me covered for the past year. Love the 28 Drag3 with a raised limiter.
Props i haven't tried but want to are 28 Hoss triton 2,27 Hydromotive T3X, and a 27 Hydromotive XOB worked by Todd. I find the 25 pitch awesome for all round use with the promax and the 28 pitchers great for high speeds and still offering decent performance down low and mid range. That leads me to believe that a 27 would be the best all round pitch for sacrificing little, all with raised limiter .Mines set to 7500 but most props above 26 to 28 run around the 7300 range most times. 25 and 26 pitchers you can bump the 7500 if ya want to at even to 1/4 bellow trimmed out till ya loose speed.:banghead
procomp
Active Member
I know the cost of ownership can be a little more with the 280 but the GS is soooooo much more fun with a 280 then a 225. No comparison.
Tried my buddys 26 prop and I tried his unlimited ecu on my stock 280 my GS went 105 motor near half inch under pad didn't have time to try my 30 hoss which went 104 with stock limiter not bad for a tuna barge, but now sold the boat so cant try for a bigger number with the 30 so I will save it for the next ride...
Dave Hensley
Well-Known Member
Everything he ever had was a RAT.....
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whipper
Well-Known Member
Jeff what you looking for this time?