from the bottom of my boat to the center of prop shaft is 10 inches is that to long to short or right any one know

Well, it depends on the application, but that sure sounds deep.

Like Cord said; We do need to know lots more about the rig but I can't imagine ANY performance application where you would want to run that deep other than some radical tunnel or cat hull that gets WAY up. --- Jer

the boat is a 27 foot single vbottom change from an alpha to a bravo boat handling changed porposises if i put a shorter drive imco would that help???

I can't imagine a V- boat builder setting something up that deep. To accuratey get that dimension you have to be trimmed EXACTLY parallel to the keel line. Extend that line to the end of the prop shaft and measure the verticle distance. Do you still really get 10"? (I know there's a joke here somewhere about overestimating lengths like that but I will leave it alone for now) --- Jer

By chance you're not measuring from the top of a notch are you? If you measure from the bottom of the hull to the underside of the gimble and add 9-1/4" you'd get the approximate x-dim.

i measured straight down from bottom of v to the center of prop shaft

I gotta believe that we're not on the same page here. Again-- the straightedge extention of your keel-line and the distance to your propshaft WHEN TRIMMED EXACTLY PARALLEL TO THE KEEL-LINE is still 10" ??? If so, you got big problems and the 2" gain from the IMCO shortie will not solve them all. Anyhow, I'd love to know how this all plays out. Keep OSO in the loop on this. --- Jer

I believe IMCO has a 3 inch shortie also.

But I believe the additional inch is in the upper unit.

I'd sure love to see a pic of your application. To have a drive set that low, the engine pan would have to be right on the bottom of the hull. The gimble, would be right on the bottom of the V. This just doesn't sound right.