53C with 1271n

[nor'easter]

I saw an add for a 1973 53C with 1271n's, i assume at 525 hp. Listed cruise is 18k ar 2100. Does that sound right? What is the rated rpm for the natural?

Thx
Paul

 

[bostonhatteras]

Powerboat guide lists 17 k cruise with 20 k top. I would imagine rpm is the same as any 71 series. 2350.

 

[saltshaker]

I saw an add for a 1973 53C with 1271n's, i assume at 525 hp. Listed cruise is 18k ar 2100. Does that sound right? What is the rated rpm for the natural?

Thx
Paul

Speed sounds a bit optimistic but not too far off. 2300 is max full load and you can run those engines at 2150 all day long.

 

[nor'easter]

Thanks, i figured the rated rpm was 2300 and the naturals would handle 2100 all day. These motors have a reported 3700 hrs on them. I know they will go for a long time beyond that if the were taken care of.

 

[rsmith]

My boat runs 18.5 kts @ 2100rpm 42 gph 500-600 gal fuel on board 100 gal water. The 53 is a couple lbs heavier but basicly the same boat.

 

[Jasper]

Speed normally on my 53 convertible is as per the above posts.

With a new bottom paint, half fuel and water and just me on board I have achieved 20.5 knots full at 2200 r.p.m

23 knots would need a big tide and wind on my stern, cruise at 2100 at 18 knot is more like full throttle once you have a fully loaded boat with a few months of growth.
FWIW, I enjoy 10 to 12 knots (or 8 when trolling) which is surprisingly economical.
Also, I was warned these would be "wet" boats. But so far mine has been absolutely fine, not wet at all. and I have had 20+ boats over the last 20 years.