Mercury advertises a variable boost controller which will electronically adjust the boost bypass to control and keep output to 1075HP. My question is how do they do this? Is there some type of Torque/Hp sensor involved? There is a picture in the 'mercury 850' thread which shows some hoses coming off the transmission, Is this for a cooler or some type of sensor? Can someone take a picture of this area of the trans. Thanks.

According to the Merc guy who gave us our 120+ blast in the 36 Skater, it is JUST a boost controller, and is aimed at ensuring more or less constant boost under "most environmental conditions" (meaning altitude, as much as anything else..).

So at sea level or 4000 feet of elevation, you should see far more repeatable performance without repulley-ing. Other factors such as humidity, ambient temp, and other such stuff is pretty much going to have the same effect on these motors as it would on a fixed boost motor.

At least that was his take on it. We talked motoers as we idled out until he brought us up to 50ish and then crammed the sticks into the dash. Nice motors. Very nice.

I may have poics of the cooler hoses. I do believe they are just that, though, as I took a double take on tyhem as well..

So basically at optimum conditions that motor should be able to exceed the 600hp, of course it will "de-tune" its self so as not to exceed the stated power. Its seems to me that its not adding power, its letting you have access to that power that would already be avalible if the computer system would let you use it.
So how long will it be before someone remaps that computer to give you maximum boost at all times?

Marty: I doubt if they use a HP sensor. There will likely be a lookup table that gives bypass valve position according to MAP, MAT, RPM etc. The XR drive is the main reason for never exceeding a given torque.

sutphen30: Yes, the blower drive belt is the closest to the crank. Accessories spaced out. Neat water pump spacers