Tell me about this X factor thing.

[f_inscreenname]

As I was staring out my garage the other day I noticed something. The Monza’s transom shield is an inch and a half higher then the transom shield on the Nova. Both 19’ boats. Both Volvo 280T. There is something going on here.

[MOP]

The higher you can raise your X the higher you speed will be. Now that is a broad statement! Raising the X will increase speed but you can easily go to far. Also many times raising the X can affect handling mostly good but in some case not good, every setup seems to be affected differently just like props. The guys running shorties have the advantage of playing with spacers to tune in the right height for their app. I did a bit of the much simpler outboard jacking setups, I have seen 10+ mile and hour gains on some boats I am sure some have done better. Raising the prop shaft height also helps with chine walk and porpoising, maybe a little more so on outboards not sure. One boat I setup many years back was a 16 footer with a 200 Johnson, it had dual cable steering, solid mounts so it was very tight. To start I had the cav plate 2" up and the boat was so loose that it would wet one rail then the other! I went to a stand off hydraulic jack, just about the time the lower would start to loose pickup water the boat settled in like it was on rails. I/O's from what I have seen for the most part are set to deep, to me even the average cruisers cav plate should should be at or just above the bottom.

[VetteLT193]

you also have to measure from the bottom of the boat, not the top. looks can be deceiving

[f_inscreenname]

I think they are about the same dead rise. The Nova is overall wider of course. There is a difference in the hulls. The Nova is rounded (I take it so to make it softer on landing waves), the Monza has a flat area about 8 to 10”s wide that runs all the way to the bow’s rise. Not sure how that affects the ride. But over all even with the hull shape difference the Nova’s outdrive is 1 ½” lower then the Monza’s.
http://img195.imageshack.us/img195/7831/77957003.jpg
http://img195.imageshack.us/img195/3095/10150188.jpg

Cav plate should be at or just about the bottom.
I have some measuring to do.

And yes I did measure from the bottom.

[MOP]

I corrected my post from about to above, my 22 came from the factory with the cav plate 2" above the bottom. Most boats when on plane still have the cav plate in the water flow, this fine for the average boater. For increased performance raising it enough to clear the flow will net some decent speed gains. It sure would be nice is someone made shorties for Alphas, all 16 & 18 Donzis are too deep (excluding late model 18's with the raised hatch). There are signifigant speed gains going to an SS, but a shortie Alpha would in the long run be a bit more reliable.

[f_inscreenname]

I need to figure out this X factor thing before I cut the Nova. A straight edge and a tape measure last night proved it to me. The cav plate on the drive is 3/4" below the lowest point of the hull. The Monza's cav plate is 3/4" above the lowest point of the hull. There is a big difference there. You say the cav plate shouldn't even be in the water when you are "haulin the mail". You never see the cav plate in this vid and it‘s going about as fast as it goes.

http://www.youtube.com/watch?v=PbrzFsgJFBM[/URL][U]

You also say “to me even the average cruisers cav plate should be at or just above the bottom”. So I take it being below is an absolute no no in a 19‘ boat?

[BigGrizzly]

The Nova does not seem to have a pad it is a round or sometimes called saucer bottom. I think you could raise it. That being said I have seen Volvo's been jacked up 2 inches and not see any gain. The SS merc is 2 1/2 inches shorter then the Alpha-that means the prop shaft highr is 2 1/2 incher higher in the sane cut out.

[BlownCrewCab]

I think if your dragging the whole cav plate and then some through the water, raising your X will show some benefit, could be allot, could be a little. You do know that raising the transom assembly requires raising the motor too, along with exhaust cut outs. Would I do it if it where mine?? Hell Yes, that way I know theres no more speed to be had there and start looking elsewhere.

[f_inscreenname]

BG, I hear what you are saying. Sometimes you have to roll the dice.
Being this Nova was built by Allmand (the super safe company) and was never meant to have an outdrive (right Brownie) I’m sure Allmand went the safe route. I mean when I put the motor (small block Chrysler) in the Monza I thought it was up to tall compared to the 454 in the Nova until Vrod showed me his Monza’s set up. I even had to build inch and a half blocks for the motor mounts Mad Poodle made for me because I judged to low.
I do have this nose cone for the drive. It was the one thing the Monza gave up for the Nova which is a pretty fair deal being the Monza was rebuilt with left over parts from the Nova.
http://img192.imageshack.us/img192/1095/96184796.jpg
BCC
Just who I wanted to hear from. Can you steer your dad in this direction? He is about the only one that has any experience besides myself with these boat.
The exhaust is in a couple pieces and can be extended if necessary. For that matter I want to change it anyway. How? Lets just say I want it to come out the transom like the steam out of a cartoons bulls nose. As for the motor. I probably could lift it 3”s before I would need a lower profile air cleaner. So that’s fine.
As for speed, to be honest, yes that is the real goal. No disrespect for your dads design and we are talking about almost 2 different boats being they were made by 2 companies, differently and inboards and I/O’s but I have found a couple things that may help on this front. There’s no lack of motor that’s for sure. The last time out it’s either running perfect or ready to blow up. The drive could be improved (not mechanically) and that’s what the cone is for. I also want to add that Volvo/Mercruiser prop shaft to eliminate the “lack of props” issue.
And here comes the fun part, the boat falls off the top of the water right about where the windshield is. That is also the point the strike ends. The Monza’s goes back another 4 to 5 feet. I would think for lift. I really want to extend them and it doesn’t look that hard.
I have a friend that has one of those sick river boats. It has a pad by the transom it rides on when it‘s going. I’ve thought of doing that also but I do like the big water and wouldn’t want to screw it up by doing it. If it was a flat water boat that back 3 feet would be cut off and rebuilt as flat as possible and it would ride with it’s nose in the air.
The main point is the boat needs changes. I hear what some of these guys are running around here and I cant even get into the 60’s with a pretty stout 454.The boat needs to get more up on top of the water and in the same breath it need to stop pushing so much drive thru it.
I have to say though that all this stuff scares the crap out of me. It’s not like you can cut an inch out of the transom and if it doesn’t work out put it back in. It is one of eight known to still be around and the only one on the water so if I screw it up it not like I can get another.

http://www.youtube.com/watch?v=IRFWD58p7YU

[MOP]

Measure from the pivot pins down to the bottom of the cav plate that will give a base line to work off of.

[BlownCrewCab]

Changing prop shafts does open up allot more choices, But I think it has been determined over time that Max speed on a (old style) volvo is mid 60's. A nosecone helps a little. You could borrow a motor from John Force and still only see mid 60's, You'd just get there quicker. The size/shape of the drive just punches a funky hole in the water as it passes through, the longer you can make your drive (front to back) the better, to a certain point where you have too much gearcase in the water.

[f_inscreenname]

MOP
They are both the same??


Changing prop shafts does open up allot more choices, But I think it has been determined over time that Max speed on a (old style) volvo is mid 60's. A nosecone helps a little. You could borrow a motor from John Force and still only see mid 60's, You'd just get there quicker. The size/shape of the drive just punches a funky hole in the water as it passes through, the longer you can make your drive (front to back) the better, to a certain point where you have too much gearcase in the water.

Mid 60's would be nice. Really nice. At the moment I can do 55 all day and the best I ever got was 57.5
I had a empty gas tank, nothing on the boat except a GPS unit, with the wind at my back and I think I was jumping up in the air at the time but it did it.:wink: I would add a mast and sail just to say it honestly dose 60.