Boatmad.com


Reply
 
Thread Tools Display Modes
 
Old 05-03-2006, 09:21 PM   #1
Taz
Registered User
 
Country: Essex
Location: Great Stambridge Essex
Occupation: Director Paving company
Interests: Boating/Squash
Cruising area: Essex Marina/crouch southeast coast

Join Date: Sep 2004
Location: Great Stambridge Essex
Posts: 2,032
What revs do the 2.5 boys pull?

Burty roofer etc etc what revs do u go up to? i know the efis have a limiter dont they 8200rpm?
__________________

__________________
[
Taz is offline   Reply With Quote
Old 05-03-2006, 09:24 PM   #2
Registered User
 
Wacky Racer's Avatar
 
Country: UK
Location: South West
Boat make: Cyclone/ Cyclone/Rinker
Engines: Merc 2.5 efi's/300XS/5.0 v8

Join Date: Feb 2005
Location: South West
Posts: 581
8500 if not pulling a skier, 7800 with
__________________

Wacky Racer is offline   Reply With Quote
Old 05-03-2006, 09:44 PM   #3
Registered User
 
Country: Norway
Occupation: Electrician, High Voltage
Interests: Boats, dirtbikes
Boat make: Hydrolift T20
Engines: Mercury 2.5EFi 260

Join Date: Jan 2006
Posts: 26
Two different kinds..

..On the 2.5 EFi.

With the A49 chip, the rev-limit is 8250 Rpm, and with the A48 chip it is 11500Rpm.

There are a couple other chip`s out there also...(A-5 I think, old stuff..)
HydroT20 is offline   Reply With Quote
Old 05-03-2006, 09:50 PM   #4
Taz
Registered User
 
Country: Essex
Location: Great Stambridge Essex
Occupation: Director Paving company
Interests: Boating/Squash
Cruising area: Essex Marina/crouch southeast coast

Join Date: Sep 2004
Location: Great Stambridge Essex
Posts: 2,032
is there a safe realible limit?
__________________
[
Taz is offline   Reply With Quote
Old 05-03-2006, 10:07 PM   #5
Traveling
 
Country: UK
Location: Alderholt
Occupation: Aerospace
Boat name: T/T D2S
Boat make: Midas 27' Cat, Argo 16 Cat. Avon Rib Thingy
Engines: Merc 280-ROS -JSRE,65Xs, 75 Stinger, Yam 60
Cruising area: Any Seedy Bar

Join Date: Sep 2004
Location: Alderholt
Posts: 4,223
Quote:
Originally posted by Taz
is there a safe realible limit?
Idle
__________________
It is impossible to lick your elbow.

Team25Racing.com

At least 75% of people who read this will try to lick their elbow!
BluFin is offline   Reply With Quote
Old 05-03-2006, 10:33 PM   #6
Registered User
 
Country: Norway
Occupation: Electrician, High Voltage
Interests: Boats, dirtbikes
Boat make: Hydrolift T20
Engines: Mercury 2.5EFi 260

Join Date: Jan 2006
Posts: 26
A49- 8250Rpm..

..is the safest of course, but this an all race engine so it requires alot of "attention" anyway you look at it.

when using the A48 chip(11500), I think you really should have a lightened and ballanced rotating assembly -it keeps the bearings of the crank/rods happy.

Watch the compression and use 3% good fully synt. oil and it will hold up..Or att least mine did..think it has alot of hours.(before I tore it down)

Edit: saw now that you had a 2.5EFi, thought you had a XR2 and was thinking of getting an Efi..sorry about that-my bad..)
HydroT20 is offline   Reply With Quote
Old 05-03-2006, 10:57 PM   #7
hello
 

Join Date: Mar 2004
Posts: 2,739
Re: Two different kinds..

Quote:
Originally posted by HydroT20
..On the 2.5 EFi.

With the A49 chip, the rev-limit is 8250 Rpm, and with the A48 chip it is 11500Rpm.

There are a couple other chip`s out there also...(A-5 I think, old stuff..)
The A5 isnt an older chip its for the 849849 ECU the later type for the 2.5. The A36 is the older version and like the A48 and A49 fits the older 11350 ECU.

For ECU's and Chips see here .
JamesM is offline   Reply With Quote
Old 05-03-2006, 11:03 PM   #8
hello
 

Join Date: Mar 2004
Posts: 2,739
Re: A49- 8250Rpm..

Quote:
Originally posted by HydroT20
and use 3% good fully synt. oil
Think you ment 32%

As for revs depends what been done to the motor. For a standard 2.5OS in good order high 7's should be okay!!!
JamesM is offline   Reply With Quote
Old 06-03-2006, 09:18 AM   #9
Registered User
 
roofer's Avatar
 
Location: GOLDEN MILE
Boat name: LILY THE PINK AND TERMINATOR 11
Boat make: PHANTOM 21 AND 20
Engines: 2.5 EFI X 2

Join Date: Mar 2004
Location: GOLDEN MILE
Posts: 2,463
Rev it to the limit, its gonna go bang anyway, so you might as well enjoy it while it lasts
__________________
PLEASE DON'T STEAL...THE GOVERNMENT DON'T LIKE THE COMPETITION
roofer is offline   Reply With Quote
Old 06-03-2006, 09:31 AM   #10
Registered User
 
Burty's Avatar
 
Country: UK
Location: Weston Super Mare
Occupation: Electrical Engineer

Join Date: Mar 2004
Location: Weston Super Mare
Posts: 6,351
Send a message via AIM to Burty
You want to rev to the limit dude cus thats where all the power is.
try around a 22" prop that should be about 8000rpm running bullet level
Burty is offline   Reply With Quote
Old 06-03-2006, 10:18 AM   #11
Registered User
 
Country: Norway
Occupation: Electrician, High Voltage
Interests: Boats, dirtbikes
Boat make: Hydrolift T20
Engines: Mercury 2.5EFi 260

Join Date: Jan 2006
Posts: 26
Re: Re: Two different kinds..

Quote:
Originally posted by Johnny Boat Dude
The A5 isnt an older chip its for the 849849 ECU the later type for the 2.5. The A36 is the older version and like the A48 and A49 fits the older 11350 ECU.

For ECU's and Chips see here .
Ok, thanks-I should have checked the biggerhammer-site first, I`m new to the 2.5 EFi-Mercury thing
HydroT20 is offline   Reply With Quote
Old 06-03-2006, 06:23 PM   #12
Registered User
 
roofer's Avatar
 
Location: GOLDEN MILE
Boat name: LILY THE PINK AND TERMINATOR 11
Boat make: PHANTOM 21 AND 20
Engines: 2.5 EFI X 2

Join Date: Mar 2004
Location: GOLDEN MILE
Posts: 2,463
Taz your engines got an 11250 chip in.
__________________
PLEASE DON'T STEAL...THE GOVERNMENT DON'T LIKE THE COMPETITION
roofer is offline   Reply With Quote
Old 06-03-2006, 07:07 PM   #13
Registered User
 
Burty's Avatar
 
Country: UK
Location: Weston Super Mare
Occupation: Electrical Engineer

Join Date: Mar 2004
Location: Weston Super Mare
Posts: 6,351
Send a message via AIM to Burty
Quote:
Originally posted by roofer
Taz your engines got an 11250 chip in.
i wish to edit my statement then.
20" prop get her screaming dude. only thing is you will need a bigger rev counter
Burty is offline   Reply With Quote
Old 06-03-2006, 08:45 PM   #14
Taz
Registered User
 
Country: Essex
Location: Great Stambridge Essex
Occupation: Director Paving company
Interests: Boating/Squash
Cruising area: Essex Marina/crouch southeast coast

Join Date: Sep 2004
Location: Great Stambridge Essex
Posts: 2,032
Quote:
Originally posted by roofer
Rev it to the limit, its gonna go bang anyway, so you might as well enjoy it while it lasts
I dont want her to go bang though thats what im worried bout , rather take her dwn to hutchy to be rebuilt then pay for a new block!! ive seen the trouble you and burty had!! weep. ......

I was bombing along at just under 80 sog and looked at the rev counter just under 8000rpm was pulling lovely just was scared bout the expensive rebuild or worse no boat for summer!
__________________
[
Taz is offline   Reply With Quote
Old 06-03-2006, 08:49 PM   #15
Registered User
 
roofer's Avatar
 
Location: GOLDEN MILE
Boat name: LILY THE PINK AND TERMINATOR 11
Boat make: PHANTOM 21 AND 20
Engines: 2.5 EFI X 2

Join Date: Mar 2004
Location: GOLDEN MILE
Posts: 2,463
If your worried about it get a set of rings fitted.
__________________
PLEASE DON'T STEAL...THE GOVERNMENT DON'T LIKE THE COMPETITION
roofer is offline   Reply With Quote
Old 06-03-2006, 08:52 PM   #16
Taz
Registered User
 
Country: Essex
Location: Great Stambridge Essex
Occupation: Director Paving company
Interests: Boating/Squash
Cruising area: Essex Marina/crouch southeast coast

Join Date: Sep 2004
Location: Great Stambridge Essex
Posts: 2,032
Yeh sounds a good idea, My compression is all even though so id like to get through the summer a little before i spend loads of dosh.
Do you know rougthly how much rings are ?
After putting a new reed in and cleaning injectors ive havent had a prob, Touch wood
__________________
[
Taz is offline   Reply With Quote
Old 06-03-2006, 08:56 PM   #17
Registered User
 
roofer's Avatar
 
Location: GOLDEN MILE
Boat name: LILY THE PINK AND TERMINATOR 11
Boat make: PHANTOM 21 AND 20
Engines: 2.5 EFI X 2

Join Date: Mar 2004
Location: GOLDEN MILE
Posts: 2,463
Rings aren't cheap about £500 ish for genuine merc hipo i think.
__________________
PLEASE DON'T STEAL...THE GOVERNMENT DON'T LIKE THE COMPETITION
roofer is offline   Reply With Quote
Old 13-03-2006, 02:00 AM   #18
Registered User
 
kiwiracer's Avatar
 
Country: New Zealand
Location: Auckland
Occupation: Construction Manager
Interests: Offshore Powerboat Racing
Boat name: NZ Privateer
Boat make: 29ft Catamaran
Engines: 2 x Mercury 300X

Join Date: Dec 2004
Location: Auckland
Posts: 214
ive got two 2.5 ROS on my boat
we like to run them at 7800 to 8000 during a race, anything lower and the power is not there and they hate being loaded
make sure they have good water pressure and good volume
i run a fully synthetic oil and mix it at 40:1
these are a full blown race motor and probably not all that suited to recreational boating
we rebuild them after 25 hours

well, thats how we run them down here anyway
kiwiracer is offline   Reply With Quote
Old 13-03-2006, 09:19 AM   #19
Registered User
 
Burty's Avatar
 
Country: UK
Location: Weston Super Mare
Occupation: Electrical Engineer

Join Date: Mar 2004
Location: Weston Super Mare
Posts: 6,351
Send a message via AIM to Burty
40:1 I was told by Jay Smith that if you are running at anywhere near 8000 rpm then you need 32:1
Burty is offline   Reply With Quote
Old 13-03-2006, 09:22 AM   #20
Registered User
 
roofer's Avatar
 
Location: GOLDEN MILE
Boat name: LILY THE PINK AND TERMINATOR 11
Boat make: PHANTOM 21 AND 20
Engines: 2.5 EFI X 2

Join Date: Mar 2004
Location: GOLDEN MILE
Posts: 2,463
I always run mine at 30/1 fully synthetic, not that its done any good
__________________

__________________
PLEASE DON'T STEAL...THE GOVERNMENT DON'T LIKE THE COMPETITION
roofer is offline   Reply With Quote
Reply

Thread Tools
Display Modes

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

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Powered by vBadvanced CMPS v3.2.3

All times are GMT +1. The time now is 03:22 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
×