.OK lets explore the deep drive issue on TRS drives. If I hold a straight edge to the bottom then trim the drive paralell to that, the center line of the prop is 5 inches bellow the bottom of the boat. That means with the 15 inch prop that the top blade is basicly at the bottom of the hull . Can anyone tell me the right way to check "X" dim and what is it on say maybe conrads? What is the ideal "X" dim on a 40 deep V Also many 40 ftrs have tripples with 400hp or so there speed is around 55- 60 there "X" dim and drag has to be terrable my trq. and the hp are almost the same with two motors waaaay less weight and waaay less drag with 2 motoers and drives . I currently run 23 mirages 5krpm and about 60-62 gps Doesent firure seems like should there should be a difference OH yea also broke a drive last week at cumberland lower gears , can any one tell me if these are the" weak link " in TRS stuff ? Wasent jumping or doing hole shots oil was fine gears just striped. thanks Dan

Fisrt of all you messured the X dim. right (-5") .
Ideal for your boat with the HP you have , i say OK.
Second i would put a 4 blade prop on it ,this will give the hull more lift.
Speed wise with the HP you have i think thats it.
If you look at a 40 foot boat with 3 engines, yes more wheight and a little more drag but its split thru 3 drives and therefor the boat is pushing easyer ,faster !

Kondrads wil maybe take your boat 1-2 MPH faster ,if that.
If you wanna make alot more speed ,you need alot more HP .
Then i would either put NEW packages on it ,like 700 MERC with NXT or go old style and beef up the motors too 700 +HP and run #3 /4/5's on it.

Or buy a faster boat and sell yours.

On your drive it is usualy the upper that breakes, so maybe just old and worn out.

I always believed the weekest link was the lower pinion.......... I got two lower gearsets on my desk that both suffered wear throught the case hardening on the pinion

TRS weaklink is the RH rotation lower gears. On the right hand drive, the pinion isnt supported as well as the LH rotation. With heavy boats like ours, we need to be gentle on the sticks while planing, and rough water is our enemy.

Im pushing 600HP per side thru my trs on my 40, which weighs similiar to yours. 70-72mph with a 4 blade. I broke my RH lower gears while running 5300RPM in some choppy lake michigan waters. Inevitable.

What HP are you running now? I have had a couple trs boats, and my buddy has one. Never had any drive issues with 420HP and under even on my old heavy 40.

I'd say go to konrads and big power, or leave it as is. The one and only thing I dont like about my boat is having to *****foot the throttles. My buddy has a 40ft cat with #3's and 575HP motors. He's been hammering on them for 15years. He pegs that tank at 4g out of the hole.

I drop my tabs about 1/2 way, drives tucked in, and slowly bring up to around 3g, and let the boat catch up to speed till it gets on top, than raise the tabs then drives. Seems to work good. If i go too far down with the tabs, (long ass 380 kplanes), they wash some of the water away from the props, and it will cavitate more.

Also, if you are running the old quicksilver mirage props, try switching to a 23P mirage plus. Will probably drop your rpms a bit, but should give you more bow lift over the quicksilvers, and maybe a couple mph. ALthough im surprised you are only spinning a 23 to 5200 with 600HP per side. I can spin a 25P 4 blade to 5500 with 600hp a side.

Never went through old drives before it broke! Probibly had some issues before I broke it . Motors do seem short on rpm ,Going to look into carb air flo only 750s even when I over trim rpm hardly moves 100 rpm or so . Boat carries the bow pretty good I think check out my pics on pics from lake cumberland thread i posted the other week . Another question may seem dumb but what the heck !Have you ever noticed when your running at plane speed or so the motor hatches are realy hard to open? Is that the suction or is it the air over the top causing a vacume or something? I have the 2 hatch stile and there is a very noticable difference. Just a thought about how much air these things need at 4 or 5 k verses a car.

As mentioned above, typically, the TRS right hand lower pinion gear is the weak link.* The lower drive gear is located behind the pinion gear and is supported by the bearing carrier.* When subjected to more torque than they were designed for, the case deflects and the gear contact pattern goes away. Most failures pull the tooth out at the root.It sounds like you have measured the prop shaft height correctly. 5" below is pretty standard for the TRS although I've seen them quite a bit deeper.*-Just for reference, X-Dimention is a different measurement.* X-Dimention is the crank shaft centerline in relation to the bottom of the hull.* Obviously, the higher the X is, the higher the prop shaft height will be.*The Konrad 540 replacement for the TRS is 1.7" shorter than the TRS.* Most installations benefit greatly from the increased height when propped correctly.* The drive is conservatively rated to handle 800 hp.* Case thickness and internal components are a third larger than the TRS*I swapped out my troublesome TRS units 5 seasons ago.* I can tell you first hand, it's the best upgrade you can do for an old TRS boat.* 5 seasons, 380+ hrs behind 750 hp blower motors in a '89 Top Gun. *The Konrad drives have TOTALLY eliminated drive failure on my boat and we gained 5 mph over the TRS set up.*Feel free to call for more info.*Kurt* 715-410-0735

I was running TRS's in a 311 with around 550hp. I was getting good used parts out of Florida from a guy named Don Carter(offshoreperformance.com). He gave me the # of his guy that rebuilt all his used drives. The lower gears are the weakest link, and like Biggus said the right rotation because the drive gear is set behind the pinion. After researching, I found out that hard shimming the rt drive adds stability to the bullitt and will increase the gear life. You need to eliminate the load ring(crush ring). I believe I doubled the thrust ring, and used shims for the Bravo drive. Because of the drive gear diameter I needed to clearance the second thrust ring(thick shim) by having a friend machine a radius into it. The Florida guys told me 700hp in a twin application is about the limit of a TRS, but you need to inspect the gearing, and replace when they start to pit. I'm guessing around 150hrs with 600hp on the lowers. The upper gears are large and last alot longer. I did start to see pitting in one of my upper gear sets, but the gears had over 500hrs on them. With all the Bravo conversions out there, you should be able to stock up on good used parts for little money.

LE