boatinbill

For those of us that have a 271 Fastech, we may be getting some help with all of our questions. PowerBoat has chosen a 271 Fastech as their new project boat. Let's see what they do to make it plane better and get more speed and handling.

boatinbill

I am confused, where is the spacer you are talking about? Is it in the trim cylinders, on the drive? How big is it, any descrption would help.

boatinbill

Thanks, I will take a look before I put the boat in this coming weekend. I have changed up to a 26 Hydromotive prop, gave me 2-3 more mph (top so far on GPS, no current was 71.8). But it is really slow getting on plane, besides the bad visibility I do not like puttin gthat much strain on the outdrive for that long.

ThirdBird

formulafastech, thats pretty interesting!! I did not know there were different holes in there. I don't believe mine have that however, mine are 1989 vintage. Sounds like you have solved the problem. No big deal to trim it a little once on plane, I mean who the heck drives around fully trimmed in anyway!?!? Sounds like Formula doesn't want to give you credit for a simple fix to a problem I have heard a lot of complaining about.

You get the troubleshooting award for the day

boatinbill

After two weekends away from the boat and manual, (both are kept at the lake house) I am here. I see the spacer you are talking about in the service manual, and I checked it on the boat. It is in the position recommened by Mercury for the Bravo3 lower unit which limits the trim down by about 1/2 inch. I will change it in the morning, hopefully give it a try and report back to the board.

Just for the record I have a '99, 271 Fastech with an HP500EFI spinning a labbed Hydromotive 26 prop. Top speed is 71.9 on GPS (average two ways) at 5000rpm, but the boat is very slow to plan.

I sure hope this helps.

boatinbill

First of all I recommend that everyone try this, it takes no money and about 10 minutes to do and will make the boat feel different.

Secondly, remember that I am turning a larger diameter HydroMotive 4 blade 26p prop.

Now the results,

The positive:
The boat planned like it did when I had a 22p Bravo on it. I never lost sight of the horizon and planed in just a couple of seconds, amazing difference. Although I did not have my GPS in the boat, I am sure I can stay on plane several MPH slower than before. It is also clear that the motor and drive are not working as hard to get the boat on plane.

The negative:
The boat listed to starboard when coming on plane, I believe this effect was made worst by the larger diameter Hydromotive prop.. This was easily corrected by applying a little less port tab. Once on plane the listing stopped as I trimmed out and the tabs could be pulled all the way up..

My Analysis: I am keeping the spacer in the Bravo 1 position (where it is now), I am sure that the drive will last longer and I can handle the list through proper tab settings (remember that the list disappeared once on plane).

Formulafastech, thanks for the suggestion, saved a lot of money as I was going to remove the Bennet tabs and buy some K-Planes just to get on plane easier.

Audiofn

I think that the reason that they do this is to avoid the liability of some one who is totally clueless from bow steering. Do not think that just because some one can afford a boat like a 383 that they have a clue how to drive it. I was talking to a guy with a 38 foot fast tech the other day and I had noticed him to be REAL flat when he was turning. Well guess what he was tucking them all the way in and pulling hard turns at speed!!!! He is one lucky camper. Could be that if his drives were set to trim in even further that he would not be dead. You guys know what you are doing so the fix is simple and you understand I think that Formula should let the dealers know about this so that they can explain it to the customer but then again you could get into a liability issue again?

Jon

boatinbill

formulafastech, here's what I have expereinced, first with the standard 24P Bravo prop, I also would cavatate/ventilate in relatively tight turns when trimmed past 4 or 5 notches (a typical running trim at cruise or higher). I had the prop worked on the following way. The Bravo 24P props run light on pitch from Mercury, around 23P average, I had is repitched to a true 22P but had extra cup added. This improved both the hole shot as well as eliminated most of the cavatation/ventilation in the turns. With the reworked prop, I generally dropped the nose about one notch on the trim indicater (3-4 nothes). I lost about 2mph on the top end and gained about 200rpm (up to 5200-5300rpm on the HP500 with a 1.5 Bravo gear case). I ran that prop for 3 years total.

This lost in speed and increase in rpm is what made me try the Hydromotive labbed 26P prop, that and the fact that Hydromotive props are supposed to provide more stern lift (help to get on plane). Although I gained almost 4mph in speed and dropped my rpm's back around 5000rpm, the hole shot suffered big time. Not only real slow, but it really seemed hard on the lower unit to run full throttle that long while trying to get on plane. But the larger diameter Hydromotive prop (4 blade) gave an even better bite in the corners than the reworked Bravo. No need to drop the trim at all in the turns, the bite is still real good.

Moving the spacer has solved the planing problems with the bigger Hydromotive wheel giving me the best of both worlds.

Hope this helps.

boatinbill

Just for kicks, here is my 271 at last year's Lake Cumberland Poker Run