repower question....

[gregr1971]

i am repowering my 18' weld craft boat, i am using a 1980 johnson 85hp now, just bought a strong running 1989 evinrude 120, what kind of performance gain should i expect? should i up the pitch of my prop?, i am turning 5600rpm @ 42mph with the 85hp.

 

[HighTrim]

Re: repower question....

http://forums.iboats.com/showthread.php?t=158083

this might help with your prop selection

 

[tashasdaddy]

Re: repower question....

you height set up is crutial, when mounting av plate 1 to 1 1/2 inches above and inline with the keel. then run if and see what the rpms are. you will see a decent pick up in performance. you're adding 35 hp.

 

[gregr1971]

Re: repower question....

well, i tried out my boat with the "new" looper 120, this thing is flat out AWSOME!! i gained 3 times the holeshot and quite a bit mph. it spins the 19" prop to 6000, seems good to me!!

 

[gregr1971]

Re: repower question....

i also noticed that the loop charged engine is sustantialy louder than my old crossflow while idling on the muffs..... why?

 

[HighTrim]

Re: repower question....

Glad to hear, dont get any tickets, lol.

 

[kenmyfam]

Re: repower question....

You just got to love those OMC V4's eh !!!!!
I really like our 140hp Looper.

 

[reeldutch]

Re: repower question....

120hp looper louder than the 85hp crossflow on muffs = bigger displacement

make shure it idles around 600/700 in gear in the water.
idle timing around 8*atdc

my 140 looper idles on muffs in the driveway at 900/1000 rpm.

good luck