Cutting a Bravo lower
 

A couple of weeks ago I posted a thread about cutting down a Bravo lower by two inches. Well we cut it today! Everything went well, thanks to Marvin Chivers and the equipment at L&W Machine. I will index the two halves and weld them together next week.

The progress continues.

The two sections are now apart and the final cut is taken. All of the settings have been saved on mill's computer. :)

Hiya Maxx! Dang------you're really gettin' into that stuff aren't ya? Looks very interesting---keep posting as the project unfolds please. :)

Hey Mark, how-ya been? I have been rebuilding and upgrading drives and have seen a couple of shortened lowers. I fell out of my chair when I heard what the price was to shorten one! Therefore, I thought I could offer a lower cost / quality alternative to folks who want a shorter drive but were apprehensive about spending big bucks on buying a Shortie or having one shortened. :)

Are you going to cut and weld the cavitation plate or make a new one out of stainless?
Just wondering,
Thanks,
Caleb

Timewarp, I am going to cut the lower cavitation plate and weld on a new piece to the upper. Kind of reversing the two.

Maxx, are you going to cut and respline the vertical shaft like the rear axle jobs you've referred to or use an imco 2" shorter unit? I've been involved in the axle jobs before and agree it should work. I have replaced my alpha with a bravo and now I've heard that the bravo is 2" longer than the alpha! I'm kinda pissed because I feel like I'm losing "free Speed" if there is such a thing. 2" shorter at 90 mph has got to make a difference since the alpha used to be there and ran fine at 70 and turned and planed ok. Keep me posted, this is cool. Greg

Greg, I did the same thing (switched from an Alpha to a Bravo) I measured both drives from the input shaft to the prop shaft and they had the same dimensions. However, the physical size of the Bravo is much larger and the overall dimension is a bit longer thus they produce more drag. This very reason is why my boat manufacturer moves the X dim up 2 inches for Bravo applications. As far as the vertical shaft goes, we can't cut and respline because the lower section of the shaft is case hardened and we would still be in that area even after taking off 2". I am going to cut the shaft in the large diameter area, stub one side, drill the other and press the two pieces together. Then weld with a stainless alloy. This should be plenty strong 'cause welding with the stainless will not crystalize the metal at the weld joint. The upper splines would twist off before the weld joint would break. I am communicating with an aftermarket, drag racing, drive train company to produce a vertical shaft at a reasonable price.

i would be interested in hearing how the project goes i might be on the customer list soon for a shorter lower myself.