Home   |  Message Board   |  Information   |  Classifieds   |  Features   |  Video  |  Boat Reviews  |  Boat DIY
Does an Evinrude Etec 75HP Puts Out 83HP - Page 2 - Walleye Message Central
Walleye Message Central

Go Back   Walleye Message Central > Boats, Motors, Electronics and Trailers > Motors and Props

Reply
 
Thread Tools Display Modes
  #11  
Old 10-16-2019, 08:02 PM
Hartly Hartly is offline
Minnow
 
Join Date: May 2019
Posts: 17
Default

Quote:
Originally Posted by wh500special View Post
I think for most of Evinrude's - and everybody else's too - normal computer-controlled engines that you should expect they produce their rated power plus or minus some small tolerance. Output would be easy to control and is directly proportional to fuel flow.

You wouldn't think they'd want to risk customer dissatisfaction with a slug, and they don't want to create higher emissions than they promise the EPA. So I would think a 75 hp rated engine would pretty much nail 75 actual horsepower most of the time.

Apparently manufacturers are allowed a +/- 10% variance on their outputs. Evinrude capitalizes on this with their various High Output ("HO") series motors. They have the computer set the output to coincide with the max allowable, so in your case your 60 HP is probably delivering 66 hp max. Bobby's 90 HO should be delivering 99 hp.

Often the advantage to Evinrude's HO series is that the motor has a comparatively higher displacement than a non-HO motor of the same rating. This will translate to increased torque output which, of course, will get a heavier boat on plane more easily. That would be the case with your 60 HO versus the standard 60.

The relationship I have seen for how increased horsepower affects the top speed of a planing hull is to divide the higher horsepower by the lower horsepower, take the square root, then multiply that result by the top speed achieved with the lower horsepower. You can, of course, go the other way and see the effect a lower horsepower would have on the same hull.

V2=V1sqrt(HP2/HP1)

V=velocity
HP=engine horsepower
1 and 2 are subscripts for the two HP cases.

So in your case, assuming you have 66 HP from your current engine and 75 from the new, you'd see a mph increase of 6.6%. So if you're getting 30 mph now, you'll get 32 mph with the larger engine. If you get lucky and get a thundering 82.5 hp version of the 75hp, you can expect a 12% gain...33.5 mph. Unless you do all your running around at full blast, you might never feel the benefits of the higher horsepower.

V2=(30mph)(sqrt[75/66])=31.98 mph


Or - much more succinctly - what DW said.

Whether these modest speed increase are worth it to you is your decision. Chances are that acceleration and planing ability will be pretty similar for both the 60 HO and 75 (same displacement motor). They both weigh the same, so it comes down to preference and cost.

Steve
wh500special. Thank you soooo much for the excellent explanation. After reading what you wrote I fully understand now. God Bless and take care . Tight Lines
Reply With Quote
Sponsored Links
Advertisement
 
  #12  
Old 10-16-2019, 08:19 PM
Boondock Boondock is offline
Wallhanger
 
Join Date: Jun 2017
Location: Pueblo west, co
Posts: 719
Default

Quote:
Originally Posted by Bobby Winds View Post
Hey.........isn't this your boat and motor . . . .
Lol looks like fun but that pics has been a bit played out

Nice reply special.
__________________
13 Lund impact 1775
1.7l 115 merc 4 stroke
2 helix si 10's
BT terrova link
Reply With Quote
  #13  
Old 11-05-2019, 07:22 AM
omc frank omc frank is offline
Keeper
 
Join Date: Feb 2004
Location: chicago, il, usa.
Posts: 360
Default

Quote:
Originally Posted by Hartly View Post
Guys is this a true statement that the Evinrude Etec 75hp actually puts out 83HP ? If so how much difference will i see upgrading from an Evinrude Etec 60HO?
No ! it does not 80 may be? but 83 would be breaking the law ratings are allowed to go + - 10% 75x1.1=82.5 no motor company is going to risk government fines and liabilities by giving you too much Hp and a posible safety isue
.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Forum Jump


All times are GMT -6. The time now is 03:34 AM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.