Caterpillar C 32

Is this the Hines Farley with the blue hardcoat insulation on the exhaust?

At those horsepower ratings you are referring to the C32 ACERT engines vs. the "standard" C32 which is 1650mhp. The ACERT is based on a completely different block and will NOT be a "drop-in" switch from C32's, not that there is such a thing anyway. The current E rating is 1950mhp and is very similar to the 1800 rated engine and have not had any major issues I'm aware of. The first run of ACERT's had some crank bearing issues that CAT rectified at a huge expense but newer ones seem to be reasonably trouble free.

Depending on what engines you have now, a change to the ACERTS may not be too simple and could entail shaft, strut, exhaust and fuel line changes that are not going to be cheap. The ACERT engines are also somewhat larger heavier which could pose a problem with engine room height and trim and balance. In frame overhauls may well be an option worth considering.

The four stroke C-32A's should definitely flow less air than the two stroke Detriots so the exhaust should be fine. Not sure what gear ratio you have now but with 1.75:1 reduction gear ratio, you will just squeak by with a safety factor of 4 which is pretty much standard for sportfishers today. She's a beautiful boat and will be even better with fresh iron, good luck!

There have been no issues related to the extra horse power upgrade that has been done to the C32 ACERT. You seem to be prepared for the instalation changes that will be required. I would recomend a marine enginieer be involved for the sizing of gear, props, shaft, fuel supply, air supply and exhaust. When this is all done properly troubles down the road can be avoided. The Dealer providing you the engines may have this service or can recomend someone familiar with CAT guidelines. Cat also has quality control systems and displays That whan installed with the engines come with the same warranty as the engines and intergrate easily with the engines. It is convienent to have one source for repairs when needed for these systems as well.

You might want to confirm that idea.

The C32 ACERT @ 1800 hp has wet turbo's. The 1950 hp has dry turbos with heat shields. We work on several boats with each and the 1950's have been just as good or better than the 1800's.

The aftercooler on both is very heavy and dead center of the engine. Many boat builders put a small hatch in the big hatch just to get them out every 1000 hours.

Should push that boat very well. Will most likely need bigger gears. Should still pick up some room. Maybe loose a little weight. Take food off some poor detroit mechanics table.

The CAT at 32.1 litres is a larger displacement than the 16V92's 24.1L but the CAT is a four stroke so as you know it only ingests a cylinder full on every other revolution. At the same max rpm's (2350) the Detroit uses 2002 CFM and the CAT 1332. I know this is a simplistic approach and there are other considerations; boost pressure, ambient cooling air, and the specs both manufacturers have for engine room depression but these are actually very close across the board for both brands and in practice the comparison of cu.in./rpm's and 2 vs. 4 stroke works very well.

I have been designing ram-air engine room induction systems for decades and am very familiar with the air requirements. The "Master" D.L.B. and I have been working together on these for some time now. On our boats we always have positive engine room pressure at all speeds which is quite unusual and while the Hines Farley doesn't have this system and most likely Delta-T airboxes, if it passed with the Detroits, the C-32A's should be well within the acceptable range.

Exhaust max back pressure for two-stroke Detroits = 2.5" Hg

Cats are about half that.

The max allowed exhaust back ressure for the C32 ACERT is 40" of H2O which = 2.94 " Hg

I would think she should have 16" exhust installed for the 16V92's which should be sufficient for the C32-A's. As a last resort I know many builders have diverted a portion of the cooling water to an overboard discharge which can bring a close backpressure reading into spec. It is definitely not the optimal solution but it has been done.

As an aside, I understand many engine manufacturers are now lowering their backpressure specifications to accomodate pod installations which have inherently high backpressure by nature of the underwater and/or through hub exhaust. Cummings and Volvo are already there and CAT will likely follow suit when their system is ready for market.

You are indeed correct.
The Cat site confirms this.
It also says that a C18 has a limit of 26.9" of water or ~2' Hg.

Being an old guy, I recall 3208s had 1.4" Hg max, but, even in the 'Legacy Engine' section in Cat.com, the specs cover all but back pressure limits.

So, my bad, stuff changes, and I learned something here which is what YF is all about.