View Full Version : Raising the x Dimension.

Moody Blu'
03-20-2003, 05:45 PM
Well, spring is around the corner and I will be starting my drive swap project soon(which will be documented for he donzi tech section).

I noticed the centerline of the prop shaft is a good 6-10 inches(not sure on this) lower then the bottom of the hull.

Would it be possible to raise the x dimension slightly without completely fiberglassing the back of the boat and recutting? I know it may not be the right way to do it, but it doesnt hurt to ask.

Regardless if the X dim can be raised with or w/out filling in the transom. One thing I am aware of that you guys might be able to help me with. The tilt mechanism on the 270 drive is fairly high up is there any possibility of raising the X dimension to a point where the ram on the drive will hit the top of the deck?

If I have to fill in the transom How should I go about doing it? (materials, etc)

I plan on welding a cone onto the drive for better flow and I have acess to a 25p stainless cleaver prop that is labbed. :D

thanks for any suggestons and help in advanced! wink

<small>[ March 20, 2003, 04:47 PM: Message edited by: Moody Blu' ]</small>

03-20-2003, 06:17 PM
Do a drive swap to a bravo and buy an IMCO shortie. Solves all your problems at once...

03-20-2003, 07:26 PM
Hey Hey Mr. Moody! If you decide to change the X dimension you will be cutting and glassing. Hopefully one of the guys up here has done it and can give you some guidance.

03-20-2003, 08:44 PM
Lenny's got it right if you're gonna do the X go Black,but get the glass out, you might find an E drive for the volvo that will raise the X a little with no glass work but the drives are few and far between and parts even less


03-20-2003, 09:11 PM
Blu, if your swappind from an older Volvo to a newer than leave it their isn't enough room to do you any real good. The trim will be enough. Remember I did this in 1995. Now if you insist talk to CDMA he has done it alot to his boat. My opinion is put in the newer Volvo and leave it. Too nuch to change going to a bravo from a Volvo with a Ford. Now the good part is you will be stronger with the Ford Volvo combo- not necessearly faster but than you don't like Chevies anyway.

Moody Blu'
03-20-2003, 10:33 PM
I should have made it more clearer that I already have a volvo 270 drive with trim and tilt. A bravo drive is out of the question considering all the work involved like griz said and the fact that I would be weakening my I/o going to a bravo.

I wouldnt consider the 270 "new" I know its the same length(top to bottom) as the 250.It is probably around a 1970 270 drive.

So theres really nothing to gain by raising my x dim?

I still think the drive is in the water to much and could be raised at least 3-5 inches

I ran my boat all last year with the pin all the way on top. I was told to be careful with the trim on the volvo drive because if I trim it to much I could burn some universals up fairly quick and possibly crack the cases.

I guess I could install the drive and ponder raising the x dimension next season?

anyone else have some thoughts on this? :)

Kent Perroux
03-21-2003, 09:49 AM
Changing to the Bravo was a lot of work. Raising the X-dim created some problems also as you will see if you ever see my deck lid. I did pick up a few mph and am very happy with the results.

I don't think it would be worth the trouble to try to raise the X-dim keeping your drive and engine. If you have power trim, I would put a hydromotive nose-cone on it, stroke your engine, and play with some really good props. You may not pick up any speed with the nosecone, but the handling is much better.

It would have been much less hastle to just drop a 400 sb in the boat. With the changes I made, it does handles better, I picked up several mph and now I have the flexibility to play with gear ratios, more props, external steering, shorter drive foots, etc; but it cost me a lot of time, headaches and $$. (And it does not look any better)