Hey Guys,

just read a lengthy thread in the General Discussion regarding the Whipple upgrades available for the Merc 600 SCI. They seem to get a lot out of the motors with very minor changes. My concern is how my drives would hold up. My boat weighs approx 9,200 lbs, dry, the Stage 1 upgrade bumps the torque on the 600's to close to 700 ft-lbs if I read the thread correctly.

Will the XR's live through that?

Thanks, Mark

Nope. That's why Merc Racing puts the NXT on their 700

For awhile yes.....I made 700TQ full dressed in a Formula 382......lasted 2 years of careful driving before loosing one of them.

Mr Gadgets,

Any Comments?

Thx

Alot depends on when the gears in your drive were made. It will last a few months or a few seasons depending on those gears. At some point, Merc switched suppliers and the quality/longevity dropped dramatically.

Either way, better get a spare drive ready to go so you don't lose time on the water. It will fail eventually.

+ 1.

I put 2 new sets in a couple of years ago.

One started to chunk out, the other one is still ok
( knock on wood)

As Smitty said, it seems to depend on the source of the upper gears. It used to be you could run 1000hp through them and it just shortened the life of them. Now 600hp and the teeth break off. If your gears are older, you have a chance driven with respect. But a Whipple makes a lot of midrange torque that will be able to break an XR.. If you want to head that way.. I suggest the SCX..

Dick