kennyo

At even trim my propshaft is 8" below the bottom (keel) of my boat. I have a stern jack on it which helps performance wise. I was wondering if I have any speed left by working on drive height?

AIR TIME

MY 24OL WAS 7'' I think put on a 2'' shortie pick uped7.3 mph with a carb change too!! went 850bg carb to 1050 nickerson dom 76 to 83.2 gps ran out of prop at 6000rpm, so it got to be good for 4mph no box. if you could get a 3'' shortie go with it it seems most of the hot vees are 4 to 5 '' stock height. and baja is always deeper, my boat flies straight now coming off of ocean swells or wakes also went from 280s k planes to 380 but leave them even or up a lil, hope that helps artie spring of 09 body back together and boat with a 572 blown 1000hpcan't wait now I hope the doc doesn't kill me on the slab soon

articfriends

iTrader: (1)

Kennyo,thats the 1900$ question,Most 272's (like mine) need to carry the bow to get any real speed at max trim BUT its a vicious cycle,without some leverage you'll never get the bow up so how how will you get the speed up? I wasted thousands putting a exstension box on after I saw how good it worked for "others" on their outlaws but I now realize my boat is not a outlaw and it went SLOWER.
I actually think a shorty will work on my boat now because I am getting too much overall lift-transom AND bow when I hold it wide open these days. My prop shat c/l is 7 1/2 inches,I have seen 272's for sale claiming to have a "special" factory x-dimension,I would not be afraid to buy a imco 2" shorty for your boat if your drive is blown anyways,you could always put in a 1" spacer if its too high,Smitty

kennyo

Thanks, I hope to dialed in soon. When that happens i'll get a speed run and see where I am compared to last year. I really don't "need " to go any faster but all the nordics are kicking my ass down here!

Wild Card 09

Having gone up as high as 1 1/2" (with a 12" box) from my stock 6 1/2" I īve experienced the problems of too high and too low drive heights.
The standard 272 drive height (my buddy has `93, I thought we measured about 7 - 7 1/2") is ok with a 3 blade and standard power. My guess is that a good labbed 4 blade would like to be at 5 - 5 1/2" and will run nice, which stacks up with Artīs experience with his 24OL.

By the way, even at 1 1/2" the boat was coming up on plane ok (a little slower, maybe) but the slip numbers were just way off.

Iīm running 2 1/2" at the moment(runs best with a 5 blade), which is probably similar to running 4 1/2" without an extension box..

Donīt bother to go for a higher x unless youīve got enough power to get over 70 mph, anyway. Otherwise it just isnīt worth it.
However Iīm looking forward to finding out how Reggie has got his 26OL to do 71 mph on 425 hp.

articfriends

iTrader: (1)

Well Ken,I got off my wallet and ordered a 2' shorty. I chewed up my 30 pitch labbed last fall and sent it in to bblades over the winter,I told him to fix it plus pitch it up to a 30 1/2 or 31 but DO NOT put the baja cup in it (I had him do it to my 26 labbed I run N/A and I do NOT like it). Well I haven't had my boat past 85 mph with the 30 on it this year because now it climbs out of the water a mile- bow and stern and is spooky like it was at 98 mph last year. I was doing some tuning with my 32 on last week and it feels normal like my 30 USED to. I figured I would try a shorty and see how it acts,I just bought the bare case/shaft,I'm putting the guts friom my spare lower in it. I'll have it by next week and will build it and have it on by hardy party in sept,I'll definately give you the full report good or bad,Smitty

AIR TIME

Hope it works for you like it did for me

articfriends

iTrader: (1)

Well Kenny, I ran the boat all weekend at Hot Boat/Hardy party with the Imco 2" shorty-Doesn't work real well (at least with my merc 4 blade labbed props). On the positive side-boat doesn't lift up like it has been BUT it drops the bow after your going over 80-85 mph and then bow steers VIOLENTLY. Saw 95 mph racing a drag boat then it suddenly dropped and I got to see the lake sideways. If you over trim it (max trim is what it always has liked) it won't carry the bow and you'll blow the prop out and get thrown around real bad (did that a couple times out of habit) (max trim on limiter which is 1/2 way up),if you trim it 1/2 way to the limiter stop which is really 1/4 trim,it doesn't carry the bow quite enough and violently bow steers after 80- 85 mph,it also starts throwing it around over 65 mph. I could probaly go to a 5 blade prop and it might be good but last time I tried that I sheared off a prop shaft with the low slip. I'm going to put my 1" spacer in and see how it acts because I have ALOT of merc 4 blade labbed props in different pitches. I'll keep you posted,Smitty

kennyo

Damn Brother, you can't catch a break! Hope you get it nailed down soon. I think I'm gonna wait and start again in the spring. I've got so used to putt'n around and don't know if I remember how to drive fast!

320es

Smitty, your boat sure seems to like the deep drive. You can always send me your shorty. Apparently they work on the 24's like mine. I'll take your beast of a motor while your at it!