I'm thinking of converting to dual cooler bell housings. I'm around 725 HP and was thinking of using one 8 plate for the engine and one 8 plate for the transmission. It appears that this will be ok but I'm interested in any input. Also It think these were used on both TRS and SSM applications? Is the bell housing the same for both or is there one that's better? I am aware that some bell housings only had one cooler...

Thanks for the help

I had a customer with an 850, 548 8-71. Single 8 plate cooler wouldn't keep oil temp below 240. Seems like the bigger power needs both plate style coolers.

the bell housing coolers for ssm and trs are the same,imo the eight plate cooler is not big enough for 750 hp,i run a fifteen plate cooler on my 1200s and never go over 200 deg.

there are a few variables in determining weather or not the 8 plate cooler will be sufficient... total system oil volume, how hard you run the boat (as in sticks welded to the dash) the harder ya load the engine the hotter the oil will get, and what the engine running temp is... all these factors influence oil temp.. IMO 8 plates might be a tad light, but hot oil isn't the end of the world... 240ish is ok USE GOOD OIL

Ha! I went from a 13 plate to an 8 plate cause the temps were too low with cold lake Michigan water with the 13 plate. Condensation issue got better with the 8 plate. I made the change after talking to a guy from Hardin marine about it .

Same here Danny... I am trying the same on my end for this summer... maybe the heat from the oil will bring my overall engine temp up...
most guys with single stage water pumps don't have that issue but we who run multiple stage pumps sure do!!

I have 8 plate cooler for my oil. The only time my oil went past 210, was in lotos warm water, holding the engines at 6000rpm for a few miles.

Normally, the oil stays about 180ish on my gauge.

I would go with the 13 plate cooler with a thermostat. This will help maintain the temp. Also, all dual cooler bell housing are the same. The only difference is if they were set up for a rear engine plate. If they were the bell housing was cut down to make up for the plate thickness to keep the trans input shaft engagement correct.

There is a certain amount of oil that still goes thru the cooler even when the oil stat is closed. So having a stat (which we all do) doesn`t mean you`re going to get the temps the oil thermostat is rated at, hence the smaller cooler.

@6000rpm+ my bearings see 200* (after cooler before engine)and the oil in the pan is about 240* according to my 2 separate gauges.

At cruise it`s 40* lower

I have dual 8 or 13 plate both cooling the 750hp engine with nothing cooling the crash box.....210deg Mercury Racing oil thermostats. Zero issues fwiw. We run 4500-6000rpm for 100+ miles at a time, so harder than the average.

On the other hand My Baja ran much cooler, never broke 150deg water or oil temp and had zero condensation.....Zero issues

Lots of great info and theories on here hard to know what's best, good question though!

Can you post more info
Engine details
Water pickup
Water pump
Hose sizes
Etc.