525 SC questions
 

Looking into buying a 525sc with 330 hours and a fresh top end for my 97 scarab 23 SCS.

Wondering if anyone with a similar sized boat has some fuel economy or mph numbers with this motor. Im just a little concerned because I read that they are fuel pigs and I don't want to be limited to a 2 hour boat trip only having a 54 gallon tank.

Let me know what you think about the motor in general .Thanks.

never owned, but used to run with a guy that had one in his 27ft profile and yes he would always say it was a fuel hog(and this was 15 years ago when gas was cheap/cheaper), he never passed a fuel stop...

I had a pair in a 36 Apache and they are fuel hogs compared to the 525 EFI's. They also need roller rockers for the new fuel instead of the flat tappets they came with.

I've had 3 (one in a 24 Baja with a chiller putting out about 650 hp after being gone through, and two in a Top Gun that had bulldog blocks swapped out). They suck fuel for sure. Matter of fact, I was actually SHOCKED now that I own a boat that doesn't have them how bad on fuel they were. I actually always liked them, even though I rebuilt two motors between the two boats along the way.

Great engines but thirsty as hell. I got 1.25mpg in my 28 Pantera with single 525SC.

I wonder if it would be a little less thirsty since my boat is fairly light ( 3750 lbs dry weight )

Currently I'm running a 330hp 454 out of an old pickup that runs pig rich and I'm constantly between 4000-5000 rpm to make up for my lack of power.

I was hoping that the blower motor wouldn't be too bad if propped right and cruising in the 3500rpm range or wherever the sweet spot is. For one, because of my 54G tank, and also, Canadian gas prices are insane. I'll put It in gallons for my American friends here. During the summer 93 octane costs around $6.61 /G. ( 1.75 /l )

cruising at 3500 rpm..that sounds really nice, but when you hear that blower sing and the wind hits your face, 3500 rpm will be all but a memory 525sc's sound soooo good over 5000 rpm.

I have wondered how something like a holly fuel injection setup would work on one and if it would make a dent in the thirsties....

Ok agreed, Ive never owned a blower motor do im sure I'd be into the RPMs pretty hard.

​​​​​I thought the same thing but if I buy this engine im sure I'd leave it turn key for at least a couple seasons.

They are really good stout dependable motors stock, and when it comes rebuild time, its not that hard to pull 600-650 hp out if it

My 97 Baja 24 Outlaw came with a 454 from the factory. Boat weighed about 4500 lbs. I pulled the 454 and dropped in a fresh 525SC in 2000. You definitely can keep out of the boost and obviously save fuel but in the end, carb'd big motors suck lots of fuel and add a blower on top, it sucks even more. They weren't built with fuel efficiency in mind. Like Griff said, I was figuring around 1 mile per gallon too in both the baja and our Top Gun. So you have 54 gallons, you're good for 54 miles, stay out of the boost and I'm sure you could get into the 75 - 80 mile range.

Thanks for the detailed info! Im definitely considering this motor. I do 62 mph now with the 330hp motor. I'm sure I'd be in the high 70s with the 525.

Would be pretty awesome. And realisticly the longest trips I go on are within range of 50 miles by far.

for comparisons sake... with a 330 hp 454 I was right at 60, raised the x 2.25 or so, and a rather warmed up 525sc has me at 83 and still playing with props.

Wow! What a difference. Must feel like a totally different boat.

Thanks for the link, informative thread. By the sounds of those HP/mph numbers I'd be doing 80 easy.

We had a new 1999 42 fountain with trip 525sc They were great engines and way conservative. They said they burned 60 gallons a hour at wot x3 and I would agree. The fuel burn plus premium fuel was stupid and back then it was $5.00 a gallon. We put high altitude pulleys on and it helped. I’m sure they could be leaned out a bit to help the fuel burn. They didn’t need the 1050 dominators on them. That being said you won’t hurt them they will
run forever !!

The only problems we had was ignition coils. They laid down stock. Replaced with msd ss coils

Wow that must have been quite the fuel bill 3x

Would be interesting to see someone compare 525sc with 1050 versus with an EFI. Bet the idle consumption would go way down....but at 5000rpm gotta believe it would be remarkably the same.