bleek

What kind of Prop???? Pitch means nothing without style of prop. does it have 3,4,5,or 6 blades? Is it a left or right hand? Is it aluminum? heck at this point we don't know. Who did the work on the 29? Is it a standard length drive or a shorty? 27 fevers are not the fastest hull but pretty easy to setup. , I could pull a 28 left hand bravo to 5200rpm on a standard length xz drive with a 502, that was making 575hp. A 540 making 602hp should be able to at least get on plane with a 29p prop, maybe the camshaft is the problem. Oh and sorry my 27 was a 1999. What drag racing shop built this engine? Bob Teague told me years ago, you can't have a drag racing engine builder build boat engines. I know its frustrating, but we need all the facts for your setup. The 27 likes trim, 4.5 is not enough, 5.5 is way better. She's gonna want to feel a little squirrelly at first but once you dial it in, its a great ride. Best prop for that boat was a lefthand Mach sterndriver with the rounded blades, but those are impossible to find anymore.

tim mccray

I had either a 96 or 98 27' Fever with an HP 500 and a 250 blower on it back in about 2000 or 2001. Bought the boat that way, it did 83 MPH on GPS with Bob Teague driving it on lake Castaic just north of his shop in Valencia Ca. I think that was about all he could wring out of it. Don't recall what prop I had. I don't think you're putting out enough power to hit your numbers. Teague has a ton of experience with Fountains, would be worth it to just pick up the phone and call him. He can tell you what set up you need to hit your numbers quicker than anyone on here can and it won't be a guessing game, he'll tell you what works and what doesn't.

540Fever

Thanks for your help here, much appreciated! I have no pulled the drive shower, never thought about it quite honestly.

Previously, I only had the 26p, so this is what I put back on the boat after trying the 29p I purchased. BTW these are both Bravo1 props. The old 26p ran decent on the boat, but I was noticing slip and as I mentioned, it was revving way higher than I liked, up to 62-6300. The outdrive was rebuilt, but used the same XR 1.5 ratio gears.

by https://www.flickr.com/photos/32474676@N02/, on Flickr
by https://www.flickr.com/photos/32474676@N02/, on Flickr

540Fever

Brave Prop - 4 blade, stainless. Not sure on who did the work, I picked this up second hand from a guy with another Fountain that ran it on his single 29'.
Lower drive is an IMCO -0 Standard length.
Not sure why you're convince a drag racing shop built this engine It was built by a pretty reputable shop that has put boats over 180mph, he's been doing marine for 35 years. So again, it's not a drag racing shop.
Trim seemed to fall off after 4.5, but even if I take it to 5.5, that isn't going to help the slip I'm experiencing.

F-2 Speedy

iTrader: (6)

this is why I asked about the drive shower and cavi plate way back, IMO that pickup tube needs to be raised to about 3/8 in, I had this issue years ago it was aerating the prop and would blow out trying to get on plane

540Fever

I have felt that when coming on plane. Typically if I pull back on the throttle a bit once it starts to nose over, I won't feel it blow out.

Would you suggest just stacking some stainless washers under the pickup tube mount? I could completely remove it just for testing.

Thanks

bleek

I would bet money on the lower unit causing your high slip numbers, that boat doesn't need a IMCO lower unit for the speeds that your running. Even the speed that your trying to achieve doesn't need a pointed lower unit, Mercury's lower is a way better alternative. How big is the water intake on the front of that drive? Its like a shovel in the front of that drive. That Pointed gearcase is gaining you nothing, actually hendering your performance. Your not the first person to have this issue with an IMCO SC drive. I know it seems strange with it being hydro-dynamically esthetic but it is not the way to go. Trust me Reggie would have put them on every boat if it would have gained .5 mph. Don't put a shorty on this boat either, that will just compound your issues. Sorry if I came across as a dickbeater, I just hate to see people struggle when a lot of times the issue can be solved with some more info. You have any friends you can borrow a XR lower from? I might have a buddy with a spare laying around

bleek

Who did build the engine? I promise I'll quit calling it a drag boat motor! Nice Chevelle, I like to call my new/old 1991 31' Scarab Viper my chevelle. Sits around all the time but is fun to get out on the water every once in a while

540Fever

I'm here looking for advice, so I appreciate the input. When I picked up the boat it came with the IMCO, so that's what I used and had rebuilt. I clearly wasn't aware of any potential performance issues running the drive.

Unfortunately, I don't know anyone local I could borrow one from. My only friend that had a boat has since sold it.

540Fever

LOL all good man. The engine was put together by Competition Marine Center here in Missouri. Interestingly, I bought the boat up in Michigan and brought it back down to St. Louis. I called up CMC because they had put another engine of mine on their dyno years ago for a tune (motor in my Chevelle actually). They called me a couple weeks later and recognized the motor as one they had built back in 2006. I guess they mark/etch the some of the parts with some sort of signature. From what I was told, they built several of these engines for Fountains as an option outside of putting in the standard Mercruiser engines. So this was one of their call it standard builds. This was originally in a 29' that was down in Mississippi, somehow made it to Michigan and now back in St. Louis.