Will the xr drive slide rite into my bravo gimbal housing with out changing anything else like the trim rams or anything.

Yes

Well...except for the gimbal bearing. The XR bearings aren't as thick leaving room for an XR's larger u-joints. You will need to replace the gimbal bearing......but that's an easy $100 part you can do yourself.

You need to replace the gimbal bearing and put spacers in the trim rams. Mercury sells a kit with all the parts needed with instuctions. I got mine from BAM. Jeff Wurl

Correct.

Thanks guys, is the xrs worth the extra money to hold up with 650 plus hp.

A regular bravo wont take 650 hp for long so it's worth a try.

the bravo will last quite longer than most think with more than 750 hp. it is the accelerating and miss throttling that kills them. brickin it out of the hole and holding it down while at speed in sloppy and ruff water will wipem out.
i have set up a conciderable amount of bravo 700-950 hp set ups. change oil every 10 hrs. eas ythrottling and moderate planing and accelerating will last you. and yes a decent while longer than a stock bravo.

I wouldnt do it again.I also changed over to XR when I built my 600hp and in two years both upper gears sets have blown. Everyone tells me merc had bad gears and that the new ones should be ok now.Well after 3200.00 just for gears and about 400.00 for bearings later and now I am thinking of going back to my spare bravo ones to gain the speed I lost between the different drives.

Nordic95

I did loose 4 mph when i switched to the XR. Jeff Wurl