Speed mods for 29 Fountain
 

I have a 1998 Fountain w/Procharged engine (~750hp) with only 5 hrs on it. Does anyone have any set-up tips for which prop and any other mods I need to do to optimize speed? (Procharger ads claim the 29 Fountain gains 21 mph with the Procharger, so far I only gained 12mph on gps from my original HP500.
What trim and tab settings work best? Overall, what do I need to do to get the "21 mph" gain or did Procharger lie? Thanks for your ideas or referrals.

I remember that test, the boat had a 21 pitch prop and ran 58 mph before the Procharger! What pitch prop did your boat come with?

Ralph,

Well 12mph is a pretty nice ROI, I don't think you will see your 29 going 95mph. Guessing you were already at 74mph.

Anyway need more info to help you out, What prop did you have? What prop are you running now? Also RPMS for top speeds? What is your X- Dim?

I hate false promises, The fastest 27 or 29 I have seen is Jim Valko's 27 running 97mph at LOTO Shoot out, and that is with massive power and stripped.

WILL;)

check your X dimension.... my drive was pretty deep which caused the typical single engine 29 Fever planing problems (i.e. bow rise slow to get on a plane, etc.). We just installed an IMCO 2" shorty with an IMCO Extreme upper - boat handles totally different - better planing, better acceleration, less bow rise. I haven't got the top end numbers yet, as my GPS speedo isn't working.... (shorties don't have speedo pick-ups).

Boat is equipped with a 525SC w/ non-stock pulley.

Good luck.

Hi Indy 27,
my 29 fountain fever with HP500 runs 70 mph (gps) with a 26" bravo prop. With procharged engine, I'm at 83 mph gps with a 30" lab bravo prop (speed was still increasing slowly but I only let the engine remain at that rpm a few seconds due to break-in period).
Let me know if you have more ideas. Thanks!

[QUOTE]Originally posted by 27Fountain
[B]Ralph,

Well 12mph is a pretty nice ROI, I don't think you will see your 29 going 95mph. Guessing you were already at 74mph.

Anyway need more info to help you out, What prop did you have? What prop are you running now? Also RPMS for top speeds? What is your X- Dim?

Hi Will!
I'm running a 30' lab bravo at 5300 rpm to get 83 mph (gps speed was still rising slowly but I only let the engine run a few seconds there due to break-in period). I tried a 2" IMCO shorty (went slower) and a 1" shorty (no improvement from stock), thus I run a standard length IMCO lower now (reggie had it dialed in right) with 5.5" keel to prop shaft X dimension. Thanks for you help and any ideas!

Hi "dirtylawyer"

I tried those, see my responce in this thread series. My X dimension is 5.5" (thus, regular IMCO worked the best). FYI, the IMCO can be drilled for speed tube (all the passages are already built into it for a speedo) I have mine drilled (IMCO supplies the instructions). What prop, pitch, max rpm, and gear ratio do you have?
Thanks for your ideas/help.

Ralph,
my boat went from 70 to 85.2 on gps, I have tried at least a dozen props and currently run a labbed 32 Bravo rh. I got 85.2 at 5200 with just myself and about 15-20 gallons of gas running in 1' chop last fall. In the summer heat I can get 84 just about any day and either way those last few mph come realy slow, about a minute or so at WOT! My boat is a 96 model and I plan on trying a 2" shorty soon, JIMV has one on his 92 27' and picked up 3 mph but lost some cruise speed. I am suprised that you saw no gain on your boat, did the shorty alter your planing time or anything else?

Ralph,

Sounds like you are dialing it in pretty good. Just a idea but once you get the break in done, you may try upping the rev limiter to 5600, I read that whipple will run them that fast for the extra 1-3 mph. to get there you may need to lab your prop.

Good luck

WILL

Hi,
What did you do to get your boat from 70 to 85 mph? How much hp & tell me about your motor.
My shorty made no significant difference in planing time, but the shorter the X dimension, the longer the planning time. My X dimension in 5.5" from keel to prop shaft with standard length drive.
My motor blew (2nd time this summer) even after it was dynoed! Two melted JE blower pistons, two "tulipped" Inconel exhaust valves, one melted sparkplug, and one disingrated valve seat!!! Good thing I kept my HP500 as a spare engine!

Ralph,
I have not dynoed my motor but I think I am probably around 640-650 hp. My Procharger is a stage II running 5lbs. of boost at wot. I have Stainless Marine exhaust and had the ECU reprogrammed by Mark Boos of Precision Marine in Kenner LA. Everything else is stock. I am testing the shorty next weekend and will post results on this thread.

Lee

Hi Lee
Do you have the HP500EFI? What's your X dimension from keel to prop shaft? How stable is your boat at 85 mph (gps) and which prop do you run? What's your top rpm? Is your boat the 27 Fountain? How many hours do you have on your engine with and without the procharger?
The reason I ask these, is I'm about to rebuild the procharged blower motor for the third time and I'm debating about a totally different design (different blower vs. 540 naturally aspirated). I've had my M1 procharger for 3 years before I blew the blower. Now I've blown 2 engines this summer (I use my HP500 as a back-up motor).
Thanks, Ralph

Ralph -

sorry for the dealy in response. My drive was pretty deep, so the 2" shorty greatly improved performance, especially planing. My motor is a 525 SC, which does not have huge power/torque on the low end, thus the planing problem. The shorty allows me to loosen up the prop early and get the boat on a plane. the best part of the shorty, in my opinion, is that it kept the bow down even when I'm trimmed out at 5.5 - 6 - felt like I added 2 ft to the boat. Thanks for the info re: the speedo, but unfortunately I already purchased a GPS unit. Right now I am running a 28P Bravo labbed by Mercury Racing. Turning it a 5100 RPM std 1.51 gears.

Ralph,
My boat is 96 27 Fountain with a 502 EFI, Bravo 1 drive, 1.5 ratio. I am currently running a RH 32p Bravo four blade labbed by Throttle Up at 5200 rpm. The boat feels great at wot, very stable. I installed the Procharger when the boat had 160 hrs and now have 235 hrs.

Lee