wildcard

CP Performance now offers a crossover kit for MPI engines that use a serpentine belt. It comes with the thermostat housing , thermostats, ports to install your engine coolant temperature sensor. A pulley is also attached to the crossover so you can use your same serpentine belt. I requested the 160 t-stats which are standard on later MPI engines . The 140 t-stats which they offer will not let you out of the enrichment mode, unless you install a 400 OHM resistor in the yellow wire of the ECT to trick the computer. This may or may not be a problem depending on whether you boat in a cold climate or not.

WETTE VETTE

I like the crossover if only to clean up that ugly t-stat housing that merc puts on the motor. Temperature and pressure issues are easily delt with. For big HP crossovers are a must for proper cooling. My .02!!

CAP071

Stock EFI motor here I was told by many stay with stock set up it's a better running system

paradigm shift

I got a used cross-over with thermostat by-pass I took off a stock 502mpi mag. Put the stock back on because motor ran to cold. Could have used a resistor I guess but it will not warm up at idle. Water pressure is/can be problem you will need to check it. You will not feel or see any gains in speed only a cleaner front of engine look. Been there done that.

Ratchet

If you're starting from scratch, and looking for a cost effective / easy to mount pump, look at a johnson. It bolts right to, and is driven off of the crank.

I needed pumps when I put my SBs in a boat with bravo's & was on a budget. Anyways, I think for 2 pumps (they are made of brass, not plastic) & the brackets (you can probably make this and save 20-30 bucks), it cost about $375 shipped.

They also make it VERY easy to change the impellers.....I took them out when winterizing & it took me about 2-3 minutes a pump, and the replacement pumps (impellers) run about $25. The only thing is that they stick out in front of the engine a bit.

It is a very easy / cost effective set up though, you just gotta re-route a bit of plumbing. I think they are used on ski-boats, but I wouldn't hesitate to use them again !

26 scarab, and a few others have seen them, and can comment on them.

Here's an addy where you can see them:

http://marineengineparts.com/shopsit...ml/page84.html

RJ

ragtop409

Yep! SHRP105
that is what was on my MasterCraft. worked great ran a hot water shower of it also. Rag's

Ratchet

Based on their recommendation & the fact that I planeed to spin it at 6000 all day long, they recommended this one :

JP10-24232-1

I think cause it was brass instead of aluminum, & because it had a wider impeller.