Bravo one to XR advice needed
 

So I'm considering changing over to XR drives from the orignal Bravo one's on my 2000 382 Fastech. Can anyone provide me with pro's /con's and what else I need to consider if I do the change over.

Thanks JB

Standard Bravos have helical-cut gears. XR have heavier straight-cut gears and a thicker propshaft. They suck up a few more HP and run the same props but need a different hub. I have Max Machine prepped XR drives on my 382 with 650 hp/650 ft. lb. and never had a drive issue.

On your 2000, you might have to do the gimble bearing upgrade. They have a conversion kit that includes a new gamble bearing, drive limiters, and the ring that holds the bellows in. With those drives and your power (500 efi's, right?) you will be bullet proof! I'm running XR's and take it easy with 650, and no problems.

Dave

I spoke with Merc high performance tech and he suggested that the X drive would be very suitable with 500 hp. Any input or thoughts on that?

Price shop it out...I didn't even think they still made X or XZ drives anymore. For the added cost, parts availability, and piece of mind...XR.

Just my $.02

Dave

"Suitable" vs "bullet proof" would be the quandry. I would go with bullet proof. Merc just seems to slightly under build the drives anyway with the high numbers of failure.

XR.

go with the Imco SCX


best Bravo Style drive

Bravo XR gears wear at a much higher rate. The xr gear life is close to a quarter of the life of standard Bravo gears. If your running standard 500's with no mods, i would run regular standard 2002 and later standard bravos. The 2002 and later Bravos have a much stronger gear set. I did the same swap on my Fastech. I switched to XR's but I am running a 700hp 540. If you switch to XR's you will also loose about 3mph off the top end. XRs also only have 1.50 and lower gear ratios. You may have 1.65 ratio now. There is a Mercury install kit for the Xrs you will need which has a new gimbal bearing and trim limit spacers for the trim rams. Jeff wurl

Thanks to all for your input. I should have something to report back on the upgrades by weeks end.

JB

I can only share my personal experience:
Swapped 496 HO for a HP 525EFI
Bravo 1x upper grenaded within 7 hours of running. The upper gears broke up. I'm already running an Imco lower.
Switched to old style XR upper and had lower gone through.
XR now on 4th trouble free season.

I remember something about needing a red dot gimbal brg. , which I did have already in there. Otherwise it is a simple bolt-on replacement.

I did a 2001 bravo to XR set-up and just as AXA pointed out, the gimble and collar needed to be changed out to fit.

I have been thinking about doing the same on mine, (tired of breaking drives) but I have boxes.
Do I still have to change gimbal bearings?

You need a brg with a red dot. The dot should be at 10 o'clock. Newer boats will have this brg already (my '05 did) The inside diameter is larger on the red dot brg. They are easy to replace: http://www.mercstuff.com/gimbalbearing2.htm This is all you need to watch for. It's a simple swap. Here is the thread I started when I blew my X. The guys on Donzi.net were awesome and I bought the XR upper from this site. http://www.donzi.net/forums/showthre...k-In-Forward-(

If you decide to go with an X drive, I have one that I'd part with. It's a 1.65. PM me for det's if you're interested.

I did decide to go with the x-drives and they were installed yesterday. So I am good to go for the weekend :)
Much lighter in the wallet though so I should get another 1/2 mph :D