Looking for more horsepower input
 

I have a 04 29ft Fountain Fever powered by the Mercury Racing 525HP with the XR drive turning a 4 blade 26p prop. Only gas 180 hours on it. I'd like to get the boat into the mid to low 80's. Was looking at the Hardin Marine Stage 2 Upgrade for Mercury 525 EFI. Just wondering if it's worth the $2k or save a little bit more $$ and put a whipple on it for an extra $4k. Just skeptical with long jevity with installing the supercharger. Also wondering if doing a prop change to a herring 5 blade?

Thanks for any help or input!!

making the power to get that speed not that big of deal, being able to handle the that boat there is bigger, sure I will hear flak from some, but 29 fountains, about a 25' boat in reality are great boats till upper 70's, after that they can be real handful.

What is your top speed today?

Ok so I posted this thread in another forum and was asked the same question. And everyone became fixated on the miles per hour as opposed to the real question on which mod to do and which is the best bang for your buck. My top speed is 78 and I run all day long around 72-73 full gear, 3/4 tank of full and 4 people.

I would agree with what you are saying. But for me to be running in the high 70s I'm right at the rev limiter. I like to have the potential to get into the low 80's. That way I'm at lower rpm's when at the 78-80 mark and still have a controllable ride.

I think you said the Hardin upgrade only adds 35 hp. That's about 2 mph and you probably won't be able to run 87 octane anymore. For a significant gain this is what I would do to my 525: https://whipplesuperchargers.com/ind...&product_id=56 If the above speed comment is based only on the boat's size, there are plenty of 22' Donzis running well over 80, some over 100. I'm not familiar with the Fountain 29 though so not sure if it is unstable at speed but any small boat is a handful over 80. I would do the Whipple kit, add real power and be done with it. JMO

Yes Hardin states it adds 35hp. Which I thought seemed s lot for a simple bolt on throttle body, spark arrestor and a computer recal. I only run 93 octane so nothing would change there. Thank you for your input ��

Our previous boat we had 525s and I looked at all the risk vs reward scenarios. There have been a few on OSO that have done the 35hp upgrade and the major consensus was nothing performance wise really changed. Spend the $, Whipple it and be done...but be ready to go thru the drive and do some upgrades. Or do your scheduled maintenance (don't forget to pressure check your headers and fresh impeller/housing a MINIMUM of once per year) and enjoy the boat for what you have. Nothing wrong with that.

I wouldn't mess around with "bolt ons" you won't see the gain you're looking for....

I would go with a properly installed Procharger myself, but nothing wrong with the Whipple kit either.....

3.3 whipple and cooler should get you to 700hp pretty easy, just remember those aren't blower pistons in there, I have seem first hand the pistons that came out of a 525 with a whipple on it and 3 or 4 were cracked......jmo

if you want to gain that speed going to need 100+, so a blower is about the best choice, procharger would be my choice..

So the consensus is to go the supercharger route. Now what's the major difference between whipple and procharger other than one is root style and one is centrifugal. I'm guessing they have different power bands? And how safe is it with factory internals? The engine only has 181 hours so it has a lot of life left before needing an overhaul. In which case would be the time to make it supercharger compliant. Also what about the the XR drive?

Talk to Eddie Young, Youngs Performance. He is a wealth of knowledge for the 525s. He can put an entire package together for you to bolt-on.

The whipple will be twice the cost of a procharger, but you will have parts to sell if you whipple it

I have a friend with a 29 Fountain that breaks a drive every year with a stock 525. Has to pin it to the dash to get on plane. My question would be how easily does your boat get on plane? If yours is like his, the drive will hate you and make you pay.

Sounds like your friend needs to go to Tres Martins driving school

Procharger comes in smoother and is easier on the drive. I really like the Whipple kit though. Engine internals are top shelf but compression is a bit high for a blower and cam is a bit stout for a blower. Also if you are running 93 octane in a stock 525 you are both wasting money and hurting performance. It's designed to run on 87. Higher octane ignites harder, burns slower, resists detonation and does not increase power where not needed. I also have a stock, single 525 boat and the Whipple kit would be my choice if I were looking for more hp.

So the 525 will run better on 87 rather than 93? That's something I wasn't aware of.

Bone stock 525 designed for 87 also the 600 SCI.

Great advice, That is who I would talk to