54C (Series I) vs. 55C (Series I) performance, popularity, etc.

[hatteras 1985]

I was out on a friend's 54C (1995/6?) w/ 12V92s over the weekend. We bummed around the Chicago skyline for a while, then took off towards Calumet, Indiana to take on fuel, where it is cheaper than the People's Republic of Chicago. The sea (lake) was almost dead calm, and the cruise was about 23 knots at 2000+/- RPM (1/3 load of fuel, no water, some holding).

Specifically, what is the performance difference between a 54C with 12V92s (1,080 +/- HP)and a 55C with 12V71 TI's (870 +/- HP) in:

a) cruise speed

b) top speed

c) nautical mpg

d) range

e) sea keeping ability (differences in hulls and weights)

f) durability and lifespan of 1292 vs 1271 TI

 

[spartonboat1]

Ask your friend what height of seas finally cause him to reduce speed at that speed. 7', 8', 9'? Curiosity compels...

 

[hatteras 1985]

Ask your friend what height of seas finally cause him to reduce speed at that speed. 7', 8', 9'? Curiosity compels...

I fail to make the connection here... 7-9 foot seas in Lake Michigan would cause anybody to stay home!

 

[jim rosenthal]

We've had a number of threads and discussions about various Detroits, but the overall concensus seems to be that 71s are less trouble-prone than 92s, which seems to have to do with the fact that 92s are wet-liner engines. 71s are not, as it's been explained to me. I haven't owned 92s- I did have 71s and of course they have numerous vices, but they are all well known at this point and there aren't a lot of surprises with them. They are noisy, they use a lot of fuel, and they leak. But they will do all of that for quite a long time if the power rating is not outrageous. 870hp out of a 12-71 is nearly a hp per cubic inch; probably about as high as you'd want to go, maybe higher.

92s have all those vices plus a few of their own. I can't comment on the relative merits of the two hulls involved- I think the 54' hull is a newer boat but my memory may be playing tricks on me here.

The most useful advice might be this: I'd rather own a well-maintained boat with 92s than one with 71s that needed rebuilt. Maybe the best thing to do is spend some time looking at one of each for the accommodations and layout, and decide which one suits you and your family best, and then get a very careful and thorough engine survey on the best candidate of that particular series that you can find.

Prices are good now, and interest rates low, so at least you're looking at a good time. And clean low-hour boats tend to live up in the GL area.

 

[hatteras 1985]

We've had a number of threads and discussions about various Detroits, but the overall concensus seems to be that 71s are less trouble-prone than 92s, which seems to have to do with the fact that 92s are wet-liner engines. 71s are not, as it's been explained to me. I haven't owned 92s- I did have 71s and of course they have numerous vices, but they are all well known at this point and there aren't a lot of surprises with them. They are noisy, they use a lot of fuel, and they leak. But they will do all of that for quite a long time if the power rating is not outrageous. 870hp out of a 12-71 is nearly a hp per cubic inch; probably about as high as you'd want to go, maybe higher.

I am used to MAN engines, which are quieter and less thirsty. My dad sold the boat I grew up running (53 Viking), now I would like to entertain the notion of 'looking' at something similar in the next couple years. Our primary stomping grounds were the Bahamas and Cuba. If a 55' Hat 1987-1989 can handle a 22 knot, 1950 RPM cruise @70-75gph, it would be my new favorite boat. I have a few destinations I would like to visit where a slow cruise would be necessary and fun. I have always liked vintage Hatteras boats, much to my dad's dismay.

Prices are good now, and interest rates low, so at least you're looking at a good time. And clean low-hour boats tend to live up in the GL area.

I have seen some of the marvels up here in the GL area. Quite stunning how clean they look, but they are usually not as updated or flashy as some of the ones you might find in say, S Florida.

 

[saltshaker]

The 55C with 12V71's will give you a solid 20kt cruise. Very comfortable boat both at the dock and offshore. The 54C is a fantastic boat and one that I hope to own someday. It became the 55C and then the 60C, one of Hatteras most successful hulls. I would stay away from the 12V92 boats and look for a good deal on a 3412 Cat boat. They will cruise almost 30Kts and slower if you wish. Cat boats will bring much more than the Detroit ones and engine service life is MUCH better with the Cats. I spoke with a Cat Tech today about this same boat and he said the 1300-1350HP 3412 is one of the best engines Cat ever built. More reliable and less problematic than the newer versions which are now cranked up to over1800 HP. You can get 10K hours out of the 3412's and maybe 2000 out of the 12V92's. Figure 100K to major a set of 12V92's and you can see why demand for boats with these engines has fallen off.

 

[Seahorse55]

Our 1983 55c gives the following performance with 650hp 12v71ti's
cruise 18kts 1800 rpm 40gph 500nm range with res.
cruise 20kts 1950 rpm 56gph 400nm range with res.
9kts 1000rpm 1000+nm range
both full fuel and water. these boats perform well in almost any sea state we have encountered in the great lakes. good luck

 

[jim rosenthal]

There are those of us who would MUCH prefer a very clean original vintage boat that has not been subjected to flashy updates....many of the folks on this forum prefer the look and feel of older boats like seventies and eighties Hatteras Yachts. There are so many bargains out there now that it is in some ways a buyers' dream market. Personally I'd rather get a clean gem that has always been well taken care of and pick my own updates selectively, as opposed to having to take out someone else's.

I am not a huge fan of Cat diesels, having owned a set, but there are a lot of 3412s out there and they seem to have given good service to a lot of people. The cost of majoring any engine that large, whether it's a Cat or a DD, is so formidable that I would spend a lot of money to get the best engine surveyor I could get on the boat. And I agree that a 3412 boat is probably preferable to a DD 92 boat, all other things being equal.

Have fun looking for your big Hatteras, it's a nice time of year, and a nice year, to be shopping. Lucky you.