Can CAT 3116 TAs 300HP be tuned for more HP?

[Reel Pursuit]

Just wondering if it's possible to get more HP out of these motors as opposed to doing a repower. How far can you go before you shorten the life expectancy or risk damage to the motors? Also, what's the likely cost to do this?

Thanks in advance!

[hubris 1]

Yes, But it makes no economic sense to do it. You need larger pistons and valves. Cheaper and easier to sell them to cat and buy 3126 at 350 hp. In my situation, [29 blackfin] the extra HP made no real difference in speed or fuel.
In fact I believe the 3116 also comes in a 350 hp model. It isnt just a turbo and exhaust modification that made it bigger.

[Reel Pursuit]

Thanks Hubris.
Did you go from 3116s @ 300HP to 3126s @ 350HP in the Backfin? That's an increase of 100HP, I would think you should pick up a couple knots with that increase.

[Blitzen]

Imho, I would not mess with trying to up the horsepower on this engine. This engine model was a real problem child for Cat. Most of the higher hp engines that were in some larger boats didn't last long.
If they are in good running condition, take them out and sell them as is and replace with the C-7 or C-9.

[Questsportfishing]

if you want speed / higher turns, and fuel that is the only option .. and it is good to great in my opinion anyway. sell what you have and get range, warranty and speed and the fuel burn is easy

[sclancy]

you should speak to a cat authorized mechanic about re-rating your 300s to 350. it can be done. we did it. it is not inexpensive BUT it can be done at a cost of about $60/hp if i remember correctly. it principally involves new or rebuilt governors and injectors along with timing and fuel setting changes. parts are around $1700 per engine and labor $1400 per engine. it allowed us to swing about a 2" larger pitch prop on a 32 express.

[Reel Pursuit]

OK I have been giving this some more thought.
So let's say I pull the 3116s out and sell them and re-power with C-7s. What kind of ballpark cost would I be looking at??

[Questsportfishing]

do the math and if you don't do it right on either a new boat, new used boat or lightweight to hp engine that is low maintenance you will loose.. the cats will not take high hp long runs without overheating or going over that thin line where speed and fuel both get trashed to do 4 knots more without getting what you wanted..

[hubris 1]

Thanks Hubris.
Did you go from 3116s @ 300HP to 3126s @ 350HP in the Backfin? That's an increase of 100HP, I would think you should pick up a couple knots with that increase.

The boat itself however will only go so fast. Even with the 100 hp it wasnt but maybe a knot faster. Fuel burn remained the same. Another consideration, despite what cat says, they are bigger. All the updates on exhaust, alternator, and air intake made for a very compact fit. I would not do that exchange again. Cat gave me 7,000 for the 3116's but the new ones only cost 37,000 for the 3126's. Minus the 7,000 it was a 30,000 dollar bill minus labor. I didnt keep track of that.

[Questsportfishing]

it would be bad for your heart if you did...

I have seen a bunch of upgrades my whole life on engines .. 8 &6.v92's 92's bolted together.. that was an interesting engine package .. , 71 series, and the smaller engines you have cat cummins volvo and even bmw and hino make some good little motors but not anything affordable and has true balance of balls and weight to hp

but a yanmar .. they have heat / paint peel.. they start, they run, they like to run fast, they do require some inter-cooler stuff but fuel burn and speed are there..
you can also work on them pretty easy.