Reply
 
Thread Tools Search this Thread
 
Old 18 July 2012, 12:43   #1
RIBnet supporter
 
Ian M's Avatar
 
Country: UK - England
Town: New Milton
Boat name: Jianna
Make: Osprey
Length: 6m +
Engine: 200 E-TEC
MMSI: 235076954
Join Date: Sep 2004
Posts: 1,937
The Viper Has to Go!

I've been running a 19" Viper prop and have finally had enough! Poor hole shot and not such a good top end. The etec revs out to 5600 no probs, and gets there impressively quickly! So poor bite from the prop and I suspect that I am getting excessive slip. I've tried a 21" Rebel but it was too much and I only managed to get 5000 rpm. The local dealer is unwilling to get a prop in for me to try, despite recommending a 19" Rev4 4 blader. I have to buy without trying, which I am reluctant to do.
So, does anyone know of a dealer who might be willing to loan a 19" Rev4 for me to try? Obviously if it is OK, I'll buy it, likewise if a ding it
One of the factors that I want to try out is engine height, at the moment I am running one hole off of the bottom as the Viper is known to run higher than some props, hopefully dropping it one hole will be sufficient. I know it is a long shot, but has anyone any direct experience of a Rev4 on an etec on a 6.5 Vipermax?
__________________
Ian

Dust creation specialist
Ian M is offline   Reply With Quote
Old 18 July 2012, 12:55   #2
Member
 
Pikey Dave's Avatar
 
Country: UK - England
Town: South Yorks
Boat name: Black Pig
Make: Ribcraft
Length: 5m +
Engine: DF140a
MMSI: 235111389
Join Date: Feb 2008
Posts: 9,696
RIBase
Not quite, but I have rev4s on my twin 115s on a 6.4 ribcraft. Originally the engines came with 21"vipers, they were the equivalent of slicks on a car, no grip & continually blowing out in the rough or in turns. Mike Vincent at South Coast Marine suggested the Rev4s & I haven't looked back. He let me try 19 & 21" on a try before you buy, I went for the 19inchers. They are a bow lifting prop, in that they "dig in" & hook the stern down, consequently I don't need to trim up as much to get the nose up.
The only downside is that they aren't as fuel efficient as the vipers, with the vipers I was getting 0.78nm/litre, the rev4s get about 0.7nm/l. I was willing to make the sacrifice for the vast improvement to the boat, they really did make so much difference to the handling.
HTH
__________________
Rule#2: Never argue with an idiot. He'll drag you down to his level & then beat you with experience.
Rule#3: Tha' can't educate pork.
Rule#4:https://www.youtube.com/watch?v=unkIVvjZc9Y
Pikey Dave is offline   Reply With Quote
Old 18 July 2012, 13:02   #3
Member
 
martini's Avatar
 
Country: UK - Channel Islands
Town: jersey
Boat name: Martini II
Make: Arctic 28/FC470
Length: 8m +
Engine: twin 225Opti/50hp 2t
MMSI: 235067688
Join Date: Jun 2005
Posts: 3,027
Ian,
I've got a 19" rev4 you could borrow except for the fact I'm using them at the mo as one of my 17"s is sh***ed.

In fact re reading your post if the 19 viper gives correct rpm's then the 17" R4 is probably a closer match. It's my 17" LH R4 that's gone U/S so the RH is available for a short period while I save up for a new LH
__________________
martini is offline   Reply With Quote
Old 18 July 2012, 13:05   #4
Member
 
Pikey Dave's Avatar
 
Country: UK - England
Town: South Yorks
Boat name: Black Pig
Make: Ribcraft
Length: 5m +
Engine: DF140a
MMSI: 235111389
Join Date: Feb 2008
Posts: 9,696
RIBase
Quote:
Originally Posted by martini View Post
Ian,
I've got a 19" rev4 you could borrow except for the fact I'm using them at the mo as one of my 17"s is sh***ed.

In fact re reading your post if the 19 viper gives correct rpm's then the 17" R4 is probably a closer match. It's my 17" LH R4 that's gone U/S so the RH is available for a short period while I save up for a new LH

How bad is the damage? Steel Developments have fixed price repairs regardless of the extent of the damage. IIRC they will rebuild a prop as long as there is at least 50% of the original remaining, worth a punt.
__________________
Rule#2: Never argue with an idiot. He'll drag you down to his level & then beat you with experience.
Rule#3: Tha' can't educate pork.
Rule#4:https://www.youtube.com/watch?v=unkIVvjZc9Y
Pikey Dave is offline   Reply With Quote
Old 18 July 2012, 13:05   #5
Member
 
martini's Avatar
 
Country: UK - Channel Islands
Town: jersey
Boat name: Martini II
Make: Arctic 28/FC470
Length: 8m +
Engine: twin 225Opti/50hp 2t
MMSI: 235067688
Join Date: Jun 2005
Posts: 3,027
Another one worth trying is a 19" Mirage plus. I've probably got one somewhere

Of course for either you'll need a flo-torq hub from Black Dog Marine
__________________
martini is offline   Reply With Quote
Old 18 July 2012, 13:10   #6
Member
 
martini's Avatar
 
Country: UK - Channel Islands
Town: jersey
Boat name: Martini II
Make: Arctic 28/FC470
Length: 8m +
Engine: twin 225Opti/50hp 2t
MMSI: 235067688
Join Date: Jun 2005
Posts: 3,027
Quote:
Originally Posted by Pikey Dave View Post
How bad is the damage? Steel Developments have fixed price repairs regardless of the extent of the damage. IIRC they will rebuild a prop as long as there is at least 50% of the original remaining, worth a punt.
There's a 1" crack at the base of every blade
Propellor Solutions (thought I'd give him a chance to redeem himself) were supposed to send me a special welding rod to have a bash with. It's hit & miss whether repairs like this work but I've given up waiting for the rod anyway, useless tw*t
__________________
martini is offline   Reply With Quote
Old 18 July 2012, 13:15   #7
Member
 
Pikey Dave's Avatar
 
Country: UK - England
Town: South Yorks
Boat name: Black Pig
Make: Ribcraft
Length: 5m +
Engine: DF140a
MMSI: 235111389
Join Date: Feb 2008
Posts: 9,696
RIBase
Quote:
Originally Posted by martini View Post
There's a 1" crack at the base of every blade
Propellor Solutions (thought I'd give him a chance to redeem himself) were supposed to send me a special welding rod to have a bash with. It's hit & miss whether repairs like this work but I've given up waiting for the rod anyway, useless tw*t
I reckon Steel Developments would sort that for 89 quid
__________________
Rule#2: Never argue with an idiot. He'll drag you down to his level & then beat you with experience.
Rule#3: Tha' can't educate pork.
Rule#4:https://www.youtube.com/watch?v=unkIVvjZc9Y
Pikey Dave is offline   Reply With Quote
Old 18 July 2012, 13:20   #8
Member
 
Country: UK - England
Town: Gloucestershire
Boat name: Osprey
Make: Osprey Vipermax
Length: 5m +
Engine: E-tec 300 G2
MMSI: TBC
Join Date: Dec 2006
Posts: 4,016
Ian,

I ran a 19" Viper on TimeBandit and it was perfect. Great hole shot and good top end.

How high is your ventilation plate above the bottom of the transom? What is your top end speed and RPM?

Does it sound like the prop is slipping when you drop the hammer ?

Chris
__________________
---------------------------------------------------
Chris Stevens

Born fiddler
Chris is offline   Reply With Quote
Old 18 July 2012, 13:44   #9
RIBnet supporter
 
Ian M's Avatar
 
Country: UK - England
Town: New Milton
Boat name: Jianna
Make: Osprey
Length: 6m +
Engine: 200 E-TEC
MMSI: 235076954
Join Date: Sep 2004
Posts: 1,937
Hi Chris,
Interesting! My experience is pretty much as PD's. Hole shot in particular is just terrible compared to many other RIBs that I have driven. With a 200 on the back of a 6.5 it should be much better than it currently is. Still I cannot shout too much until I have found a prop that performs better
Ian
__________________
Ian

Dust creation specialist
Ian M is offline   Reply With Quote
Old 18 July 2012, 13:51   #10
Member
 
Country: UK - England
Town: Gloucestershire
Boat name: Osprey
Make: Osprey Vipermax
Length: 5m +
Engine: E-tec 300 G2
MMSI: TBC
Join Date: Dec 2006
Posts: 4,016
Something to consider is that with the 200HP E-tec which is the same block as the 150 & 175 they remapped to get the additional top end power however in order to do so bottom end torque had to be sacrificed.

Could explain why the 150 had such good hole shot.
__________________
---------------------------------------------------
Chris Stevens

Born fiddler
Chris is offline   Reply With Quote
Old 18 July 2012, 15:15   #11
RIBnet supporter
 
Ian M's Avatar
 
Country: UK - England
Town: New Milton
Boat name: Jianna
Make: Osprey
Length: 6m +
Engine: 200 E-TEC
MMSI: 235076954
Join Date: Sep 2004
Posts: 1,937
Maybe, although when the boat is loaded I can get the prop to spin when trying to power up, for instance powering out of the trough and over the backs of waves is one particular time I can remember. I think the hole shot and poor top end is down to the prop, hopefully time will tell.
__________________
Ian

Dust creation specialist
Ian M is offline   Reply With Quote
Old 18 July 2012, 15:30   #12
Member
 
Country: UK - Scotland
Town: Glasgow
Boat name: Thunder
Make: Halmatic Arctic 22
Length: 6m +
Engine: 2 x 150 Etec
Join Date: Oct 2008
Posts: 521
I changed from Viper to Apollo props, much better grip and about £200 cheaper as well.
__________________
GordyP is offline   Reply With Quote
Old 18 July 2012, 15:51   #13
Member
 
Country: UK - England
Town: Northwest
Make: Humber
Length: 5m +
Engine: Merc 60
Join Date: Jul 2011
Posts: 79
Guys

Sorry to ask a stupit question but could you explain what hole shot means, good or bad. heard this expression a few times and haven't a clue what it means

Cheers

Buzzin
__________________
buzzin hornet is offline   Reply With Quote
Old 18 July 2012, 16:01   #14
Member
 
martini's Avatar
 
Country: UK - Channel Islands
Town: jersey
Boat name: Martini II
Make: Arctic 28/FC470
Length: 8m +
Engine: twin 225Opti/50hp 2t
MMSI: 235067688
Join Date: Jun 2005
Posts: 3,027
Quote:
Originally Posted by buzzin hornet View Post
Guys

Sorry to ask a stupit question but could you explain what hole shot means, good or bad. heard this expression a few times and haven't a clue what it means

Cheers

Buzzin
from wiki:

Quote:
This term can also be used to describe the starting performance of a vehicle. A vehicle that is fast off the line (though not necessarily fast overall) is said to have a good "holeshot"
__________________
martini is offline   Reply With Quote
Old 18 July 2012, 16:24   #15
Member
 
Oscarguitar's Avatar
 
Country: UK - England
Town: Poole
Boat name: Half Cut
Make: Cobra 8.6
Length: 8m +
Engine: Verado 275
MMSI: 235104619
Join Date: Jun 2011
Posts: 381
I have a Rev 4 19" and my understanding is that it is a stern lifting prop allowing you to plane at lower speeds. I struggle to get the bow up even trimmed right out but can plane at 10 knots. They work really well on heavier boats. Generally you can run them high, they have fantastic grip, rarely blow out and great hole shot. Not the best for top speed but good for cruise and better than most for manoeuvring.

However all boats are different and what works on my boat might be rubbish on yours. What ever you get make sure you get it balanced even if new. I tried a new 21" (higher top speed but WOT too low) and it felt like a blade was missing at 2300rpm.

Check out the hull truth forvlots of views.

Have fun
__________________
Oscarguitar is offline   Reply With Quote
Old 18 July 2012, 16:47   #16
Member
 
Ribochet's Avatar
 
Country: UK - N Ireland
Town: Rostrevor
Boat name: Ricochet
Make: Redbay
Length: 7m +
Engine: Twin F115 Yams
MMSI: 235083269
Join Date: Oct 2011
Posts: 930
Quote:
Originally Posted by buzzin hornet View Post
Guys

Sorry to ask a stupit question but could you explain what hole shot means, good or bad. heard this expression a few times and haven't a clue what it means

Cheers

Buzzin
Hole shot a measure of boat/engine performance much like the 0-60 time quoted for cars.

It refers to the time it takes for the boat to get on the plane from dead stop at maximum throttle
__________________
Maximum Preparation - Maximum Fun
Ribochet is offline   Reply With Quote
Old 09 August 2012, 07:40   #17
Member
 
Country: UK - England
Town: Northwest
Make: Humber
Length: 5m +
Engine: Merc 60
Join Date: Jul 2011
Posts: 79
Cheers Guys

You dont ask, you dont get.
__________________
buzzin hornet is offline   Reply With Quote
Old 04 June 2013, 08:07   #18
RIBnet supporter
 
Ian M's Avatar
 
Country: UK - England
Town: New Milton
Boat name: Jianna
Make: Osprey
Length: 6m +
Engine: 200 E-TEC
MMSI: 235076954
Join Date: Sep 2004
Posts: 1,937
I could not resist the weather today, so I have been out prop testing. The conditions were just right; a slight chop to 'unstick' the hull, but nothing to cause me to back off.
The boat was originally provided with the engine set at this lowest setting. I was running a 19" Viper at one hole up from the lowest engine height. This is where the Viper seemed happiest and Mike Vincent has told me that the Vipers like to run 'high'. At this setting I saw 5900 max revs. On the basis that I had to start somewhere I bought a 21" Apollo of the same diameter. The first thing that I noticed is that there is a greater surface area to the blades of the Apollo.
I ran it at the same height and it ventilated some, particularly in the turns, but I could only pull 5300 max revs. I have now dropped the engine by one hole and the boat feels a lot better. No ventilating in the turns and I can really feel the boat accelerate, as opposed to just spinning up the Viper as it did before . The numbers are still 5300 max revs, best one way speed 48.2 knots, with 43.5 knots on the return leg. This is a good 2 to 3 knots up on what I was seeing with the Viper. The tanks were almost full, 200+ litres, and one pax on board.
Before I go out and spend another £400+ on a 19" Apollo, does anyone think I should be looking at something different?
__________________
Ian

Dust creation specialist
Ian M is offline   Reply With Quote
Old 04 June 2013, 08:51   #19
Member
 
Country: UK - England
Town: Royal Wootton Bassett
Length: 8m +
Engine: 250
Join Date: Jul 2008
Posts: 8,041
According to Evenrude you reach your max 200hp at 5350 RPM which is in the centre of the recommended Full Throttle RPM Range 4850-5850 tr/min
__________________
whisper is offline   Reply With Quote
Old 04 June 2013, 11:19   #20
Trade member
 
OSPREY RIBS's Avatar
 
Country: UK - England
Make: OSPREY
Length: 5m +
Join Date: Nov 2005
Posts: 159
Quote:
Originally Posted by Ian M View Post
I could not resist the weather today, so I have been out prop testing. The conditions were just right; a slight chop to 'unstick' the hull, but nothing to cause me to back off.
The boat was originally provided with the engine set at this lowest setting. I was running a 19" Viper at one hole up from the lowest engine height. This is where the Viper seemed happiest and Mike Vincent has told me that the Vipers like to run 'high'. At this setting I saw 5900 max revs. On the basis that I had to start somewhere I bought a 21" Apollo of the same diameter. The first thing that I noticed is that there is a greater surface area to the blades of the Apollo.
I ran it at the same height and it ventilated some, particularly in the turns, but I could only pull 5300 max revs. I have now dropped the engine by one hole and the boat feels a lot better. No ventilating in the turns and I can really feel the boat accelerate, as opposed to just spinning up the Viper as it did before . The numbers are still 5300 max revs, best one way speed 48.2 knots, with 43.5 knots on the return leg. This is a good 2 to 3 knots up on what I was seeing with the Viper. The tanks were almost full, 200+ litres, and one pax on board.
Before I go out and spend another £400+ on a 19" Apollo, does anyone think I should be looking at something different?
At 5300 RPMs the engine is "lugging" you should be looking to get 5600 RPMs minimum and no more than 5850 when normally loaded. (2 up, full tank of fuel)

You should have the ventilation plate on the e-tec set 2" above the bottom of the transom and fit the Viper 2 19" prop you should be good for 48 knots with the 200HP and this set up.

This is a proven set up on this boat / engine combination. I am surprised you had issues with the Viper as you stated it has always produced the best results on previous 6.5 meter ribs.

Drop me a PM with your phone number and I will have a chat with Mike Vincent tomorrow to see if he has a 19" Viper 2 you can test.
OSPREY RIBS is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

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




All times are GMT -5. The time now is 09:34.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2020, vBulletin Solutions, Inc.