Speed for a 48 YF

[rwappleton]

What speed should I expect out of a 48 YF with 8-71's. Both cruise and WOT. Lets assume that there are not issues with the engines and it has correct props.

My brother who is a geek found a blog that repower was a must for this boat.

Opinions please!

 

[Tom and Carol]

What speed should I expect out of a 48 YF with 8-71's. Both cruise and WOT. Lets assume that there are not issues with the engines and it has correct props.

My brother who is a geek found a blog that repower was a must for this boat.

Opinions please!

If natural's my 1974 YF cruises at 16 knots when things are PERFECT! Most likely 14-16.

 

[lumina]

Hi All,

Our 1974 YF with 8V71 naturals cruises at 13.5 to 14 knots at 1850 rpms. At WOT which we hardy ever run we do 16 knots at 2100 rpms.

 

[saltshaker]

Hi All,

Our 1974 YF with 8V71 naturals cruises at 13.5 to 14 knots at 1850 rpms. At WOT which we hardy ever run we do 16 knots at 2100 rpms.

Gene,
You should be hitting 2300RPM's WOT. 2100RPM WOT is very overloaded.

 

[lumina]

Hi All,

Jack,

My fault, I should have said "our WOT limit" ie the highest we ever run her. I'm kind of chicken to bring her up past 2100 rpm, I know it's silly but I have an irrational and incorrect notion that it's bad for the engines. I think I need therapy.

 

[saltshaker]

Hi All,

Jack,

My fault, I should have said "our WOT limit" ie the highest we ever run her. I'm kind of chicken to bring her up past 2100 rpm, I know it's silly but I have an irrational and incorrect notion that it's bad for the engines. I think I need therapy.

Those 8V71N's will run forever at 2100RPM. Even at WOT they are probably putting out less HP than an 8V71TI at cruise. Don't be afraid to let them run.