Bravo XR Capabilities?
 

I know its a questions with alot of variables, but what horsepower would you start to worry about the xr and doing damage to it? This is assuming you were very gentle on the sticks getting up on plane.

Thanks!

Its the Bomb!
 

625-675HP and 625-650lb/ft of torque is about the tops you can expect to get a Bravo XR to live with, even when you are easy on the stix! The new ones with newer gears seem even a little weaker than the older XR Bravo's. seems the gears don't hold up as well, so say many users and rebuilders.

Best Regards,
Ray @ Raylar

Agreed.
600-625 on both hp and torque.

There is a reason Mercury put the NXT's on 700's. I popped three XR uppers with my twin 700's..... once while cruising at 65mph!

Same here, popped 2 uppers in my Imco SC's but their just XR gear sets anyway.

Wow, thanks for the responses! I actually didnt think it would be that low. What would be the next logical upgrade for an 800+ blown motor? Is it possible to beef up the internals on the xr or would it make more sense to go with something else?

Depends on boat weight. BMAX is a good option and so is Arneson bravo conversion

Boat weight is 4500. Magic Sceptor 28

Agreed, anymore than 650 you're really pushing your luck. You need a SCX Extreme.

EDIT: In fact, this just popped up in the classifieds. I'd JUMP on it. You won't find it this cheap again.
http://www.offshoreonly.com/classifi...o40681-en.html

Arneson ASD#7M. Bulletproof and more efficient than any normal or upgraded Bravo.

I'm running 625 hp and 670 tq on a 42 cig Tiger straight bottom. Had one lower failure at 472 hours. drive it right and no worries.

The higher torque of blown engines will eat them much quicker than a NA engine of equal hp. A blown 800 hp engine will eat a XR pretty quick!

BTW, that's a great buy on that SCX! That drive will hold up to your engine...

that won't work so well, have a friend dealing w/ about that much hp & upgraded xr's right now & it is not go'n well! Good luck!

So what exactly happens when a drive is blown (obviously I have never destroyed one)? Is it one of those things where it can possibly destroy the outer casing, or just the internals? I guess basically what Im asking is if I should just run it until it blows then upgrade, or sell the brand new xr?

With that Imco, can I still use the bravo props as well as the existing hydrolic steering components or would I have to replace everything?

Thanks so much for the information everyone is providing!!!

If you blow the upper, the top cap of the drive will blow off. If you blow up the lower by breaking the prop shaft, goodbye propeller.

When the big quick torque of lets say a Whippled 800HP big block blows a Bravo XR, generally it ruins the case and most of the upper internals to the point where it will never be a good drive again. Don't waste the value of the new XR trying to use it behind such an engine. sell it and invest that value in a Imco SCX and do it right to start.

Best Regards,
Ray @ Raylar

I've got blown 800hp motors, and have a couple hundred hours on my XRs with no failures.

10K lb boat...and even flogging it in some swells with some (accidental) missed re-entrys.

I think the key is to pull them apart a little more often, run good oil, and don't hammer it out of the hole like you have sixes.

Not sure what you have for drives now? Reg Bravos have just aluminum housings, they blow apart and ruin the housing about every time. XR's have a steel tower but it is not replaceable, stronger and can survive sometimes, basically just stronger but can be easily destroyed. Imco SC's have all XR internals but the housings are rebuildable and can most times housings be saved. They are really just XR's with a stronger housing. The SCX's are a different animal all together. Bigger gears and much stronger. SCX upper with the SC lower is the better way to go if you need to stick with a bravo type set up. ASD#7 is the way to go if your pockets are a little deeper and you can do the re-rigging within your budget The SCX lowers are bigger and stronger but have been shown to lose some speed due to their size. Lots of variables huh?

Imco SCX uses stock steering and bravo props. With any blower motor You are wasting money and time with the XR. SCX with SC lower is the best answer for you. Sell the XR while you can.

So is it as simple as just pulling the xr off, then bolting up the scx, then buttoning up the steering, etc? Dimensions for the steering hooking up to the scx all the same?

Damn, this boating thing gets pretty expensive.........:lolhit:

No not that simple but not hard. The SCX requires that you change the gimble bell with their bell to accommidate the larger head of the SCX unit. The new bells are about $1000. each

My experience is very similar with some previous comments 39', twin blown 800's, XRs with Imco lowers, no problems but am careful coming out of the hole and re-entry's, also increased maintenance (20 hr oil changes)

There is no such thing as a plug and play conversion. Some are easier than others, but all invoves some rigging and dialing in.

And with 800 hp in frot of a bravo style drive, the price goes up really fast too. Ever looked into the Arneson bravo conversion?

Yeah I have, but at ~20k + my pockets would be extremely anorexic!!! lol

Not much to it. Swap out Gimbal and replace oil reservoir. Everything else bolts up. A blown drive can do alot of damage to your boat and motor.

I have blown 800HP on a flat bottom top gun. Now I do have teague billet top caps to help. I have had no problems with my drives. Its all about how you treat them if they survive or get blew up!

I'm going to be selling everything off of the back of my boat in a few weeks. Stellings extension boxes, External steering, HP gimbles and Imco SC'c with -2 shorties. Everything is in great shape, planning on going to the ASD7 conversions. $20K for everything seems like a quick sale price.

Sorry for the hijack This thread has me wondering! I'm running a XR with a 502 EFI mag, M3 procharger and bigger cam ETC @5LBS of boost have no clue what its making for HP. I'm starting to think I'm in the danger zone as well. In a 27' fever.

it's a little bit of how you drive and Alot a bit luck. I didn't buy my boat to take it easy and if I can't use it I don't want it. I was some what easy on mine and have gone thru 2 XRs and 2 Teaques. One caused coupler to fail, took out Wye pipe and did alot of damage. SCX is worth the price...

How about the Konrad package?

I dont know anything about them. Im kinda new to the drive thing. What are the pro's / con's compared to the others that were mentioned earlier in this thread?

Not to hi-jack, but my '99 Scarab came with standard B1's. I'm easy on the sticks and would like to bump up the HP at some point (keeping it naturally aspirated.) Any thoughts on what the B1's can handle?

I have the scx extreme with just under 700 hp and im not to sure thats even strong enough..

Imco
 

I have 2 questions...

How much would it cost to replace an XR drive
with an IMCO SCX drive?...

Also, if the imco drive is too much and not an option,
can't you just upgrade a bravo drive for alot less money, and would it be as strong as the SCX Imco drive?...

Mercury used to say 500hp max on B1 before the XZ and XR came out. I would say 450hp to be safe

My boat weighs 10,500 pounds dry with about 625 hp and I've had my share of problems with my XR's and shorties. I do believe much of the problem is that I boat in the slop of Lake Erie. It's hard not to have a day when your not launching out of the water. Because of this, I'm currently doing the Arneson Bravo conversion. That being said, I also looked hard at the IMCO drive and it ended up being my second choice.

I think mine was around $13.000

Hey thanks! I was wondering about how much they are. Ya, that's really alot of money.... wow

Yep.But you get what you pay for..I think

might be worth to look at the konrad and bmax too...just sayin...

Plus they look great too... The IMCO drives really look nice on the back of a boat.... Not sure if I like the black or silver finish better... Did u have a color option on yours?