Drive Upgrades
 

As I am considering shorties, I have been trying to determine how far I need to go with upgrading my drives. The most inexpensive route is take the internals from the lowers and put them into the Imco lower ($5,000 including labor). Or, I could try to sell the Bravo lowers as is (100 hours), buy the lowers with the XR prop shaft and various upgrades ($8,000). Or, have the uppers gone through replacing with upgraded parts (mine start with OL) along with new lowers ($5,000 uppers + $8,000 lowers).

I spoke with Mr. Gadgets and these are the options he is offering. **** encouraged me to seek opinions. Thanks

Yeah, I was in the same position about 4 years ago that you're in right now. I bought some -2" IMCO shorties about 4 years ago and was going to swap out the internals from my stock length Merc XR's. I needed the 2" shorter vertical shafts and ordered them from Max Machine Worx. I wasn't in any big rush as I was still able to run my boat without the IMCO shorties until I was ready for them. I was patient and just kept buying parts until I finally had all the internals without having to swap them out.

Mr. Gadgets did all the work and he is extremely good at assembling those Bravo drives!!! I finally had the shorties stalled last year with JimV's help...But I doubt I would use Max Machine Worx any longer....for buying several THOU$AND $$$ worth of parts from them their service and attitude is less than desirable----at least that has been my experience with them. It seems they are very nice and accomodating when you're buying something from them, but I have found out very quickly that's about where it ends! Anyway, Mr. Gadgets has all the "skinny" on that----he will get you dialed in with the correct up to date parts if needed.

Dude what's with the mud in your Drain pan ? :drink:

Hope the beast gives ya another great summer !!

Cougarman

For the lowers alone your looking at a $3K differencefor XR vs. regular bravo parts. If you sell the stock lowers complete they aren't worth alot. The uppers are what usually blow leaving the market with more lowers for sale then uppers. (I've been looking for a cheap lower to add to a 1.65 upper I want to sell, figured I'd have a better time selling a complete drive instead of just the upper) I see stock lowers in good condition selling as low as the $400's on ebay and am waiting to snatch one up under $500 if possible. (They do go higher sometimes, but that's all I'm willing to spend)
So your stock lowers aren't worth the $3K difference in price, but you would end up with XR parts if you go the $8K route....what power are you running and is the upgrade worth the price? (Figure someone may give you $750 ea. for your stock lowers but it may take awhile to sell them at that price.)

This is just my $.02, good luck

Hi John, that "mud" is from getting some fish line wrapped around my propshaft/seal on my stock lower---I guess a little water made its way in. No problem, it just so happens that we had two new seals in stock---as a matter of fact, the nice thing is that they were already installed on a couple of -2" IMCO lowers that we had laying around in stock too---how convenient!!! :D

t500hps, that's about what I spent ($8000) for the -2" IMCO lowers and XR internals. Heck, then I had to go out and spend another $2000+ for some Hydromotive P5X 5-bladed props so the boat would get on plane---the 4-blades just weren't getting the job done any longer! It was a lot of SMACK to lay down, but I LOVE how the boat handles/rides compared to the stock length Merc lowers with no nose cones. Still testing, but so far with the swap alone I gained something like 5-7mph on top which comes to roughly $1428-$2000 per ONE MPH gained. I guess the way I look at it is that I would prefer to have done it this way vs buying a supercharger with more stress/wear on parts. Besides, the boat has a much improved handling attitude and ride with the shorties. Who knows, maybe a supercharger could be in the works next time the engines are freshened. ;)

I am running 700 hp NA. Peak rpms are at 5800 on the dyno sheet. Kaama brings up a good point. I may not be able to get on plane with 4 blades. Will the stock drive be good enough to handle 5 blades with shorties?

Does going to shorties put any additional stress on the drives? I probably won't be able to use my Hydromotives with shorties, either going to a labbed bravo or cnc'ed prop.

I can't remember the length/kind of boat you're running, but with 700hp you should be thinking about upgrading your drives with XR parts and have them blueprinted for assembly. Mr. Gadgets can do that for you.

I am not sure if a 5-bladed prop puts more stress on a drive or not----it seems like it would, but with a higher X-dimension maybe not. Also, I don't understand why you wouldn't be able to run a Hydromotive 5-bladed prop! (???) It takes a lot of trial and error---but I don't see why it wouldn't fit.

Thanks for the reply. I have a 35' single step 2001 Fountain. It came from the factory with 502s, which I just had bored to 540s at the end of last season after 100 hours. I'm just not sure if both the lowers and uppers need to be upgraded, just the lowers or just swap the internals into shorties with no upgrades?

Do all the upgrades you can right up front,fairly large boat with medium power plus you plan on 5 blade props,why do it twice? 5 blade props kill parts,blow teeth off uppers,shear off shafts,etc,combined with your size of your boat I wouldn't think twice,you really should have the xr parts and the best upgrades you can find,Smitty