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-   -   Sv29/ilmor 725/indy (https://www.offshoreonly.com/forums/general-boating-discussion/285472-sv29-ilmor-725-indy.html)

peterunwin 12-21-2013 06:01 AM


Originally Posted by Wobble (Post 4044643)
Man this is an awesome thread, curious about one thing. Years ago when I did some racing in England, the owners car was in Gulf Oil (tribute colors) after a few meetings he got a cease and desist order on account of the color scheme and logo being copyrighted. That was a long time ago, guessing this is not an issue anymore?

Hi Wobble,
I haven't heard of anybody being challenged recently but i am contemplating asking permission to use their logo's in a modified format.

Peter

peterunwin 12-21-2013 06:11 AM

1 Attachment(s)
Hi All,
The link below shows the difference between standard flow and pressure compared with increased flow and pressure, this helm has already had the valving modification and has been run as a motor for an hour in each direction, this gives a very smooth and notch free operation. The modified helm has virtually no free play about centre when used with the increased flow so the steering is much more precise.


http://www.youtube.com/watch?v=Xgueg...ature=youtu.be

Peter

7075T6 12-21-2013 11:25 AM

Pretty close to my numbers. I run about 1400 psi and 12-13 l/min on my twin Arnesons. Possible to go to 25-28 l/min but 12-13 seems to work best.

Toffen 12-22-2013 03:41 PM

Hi!

Although I have no inboard set up I have been boating fast with a single for some years. My engine back in time had a torque master lower unit and a sea star pro steering. Sensitive and fairly accurate. The thicker skeg should in principle increase drag, but it elimated crabbing at speed. So I gained some mph and experienced almost no torque compared to my ol Johnson V8 3.6 GT twin spark setup.

Then I had twin Merc 2.5 efi ss engines with counter rotation and latham steering. After that back to a single Verado 350 sci with power hydraulic steering. Precise if bleeded properly, but if not you loose 2-3 mph quickly. The lower unit has a straight skeg and I wonder if I should add a torque tamer. And most likely gain speed since I jack the engine high.

Back in time I read about a Laveycraft evo 28 race boat where they modified the skeg of a NTX drive and gained 3 mph. If I am correct you did modify you lower unit. What did you do?

Good luck!

Cheers Toffen

peterunwin 12-31-2013 09:24 AM

10 Attachment(s)

Originally Posted by Toffen (Post 4046061)
Hi!

Although I have no inboard set up I have been boating fast with a single for some years. My engine back in time had a torque master lower unit and a sea star pro steering. Sensitive and fairly accurate. The thicker skeg should in principle increase drag, but it elimated crabbing at speed. So I gained some mph and experienced almost no torque compared to my ol Johnson V8 3.6 GT twin spark setup.

Then I had twin Merc 2.5 efi ss engines with counter rotation and latham steering. After that back to a single Verado 350 sci with power hydraulic steering. Precise if bleeded properly, but if not you loose 2-3 mph quickly. The lower unit has a straight skeg and I wonder if I should add a torque tamer. And most likely gain speed since I jack the engine high.

Back in time I read about a Laveycraft evo 28 race boat where they modified the skeg of a NTX drive and gained 3 mph. If I am correct you did modify you lower unit. What did you do?

Good luck!

Cheers Toffen

Hi Toffen,
The lower unit is blue printed and symmetrical it also has a considerably shorter skeg. The bottom of the gear case is level with the bottom of the hull, i have left enough material in the skeg to warp it if necessary. I am also running a 139 gear ratio which means i can run less pitch reducing side ways force, this coupled with the modified hydraulic system should reduce the skeg warpage to a minimum if at all. I have also made some carbon fibre throttle paddles more suited to the shape and size of the Outerlimits steering wheel, things are progressing very nicely for our return in February.

Peter

peterunwin 01-15-2014 07:53 AM

Hi All,
Final version of the steering system is now complete, i decided to go for an even larger capacity helm to reduce the number of turns lock to lock to 1.9. Once again this has been run as a motor for an hour in each direction to give a very smooth operation and has also received the valving modification. all the aluminum parts have been black anodized and the carbon fibre two pack lacquered, can't wait to get back to give it a try.

Peter

http://www.youtube.com/watch?v=eoZmX...eature=mh_lolz

TylerBurich 01-15-2014 11:03 AM

Very Nice!

C_Spray 01-15-2014 10:18 PM

You've been a busy boy. Interesting to see someone so versed in hydraulics and electronics tackling the high-performance marine applications.

7075T6 01-16-2014 04:33 AM


Originally Posted by peterunwin (Post 4057234)
Hi All,
Final version of the steering system is now complete, i decided to go for an even larger capacity helm to reduce the number of turns lock to lock to 1.9. Once again this has been run as a motor for an hour in each direction to give a very smooth operation and has also received the valving modification. all the aluminum parts have been black anodized and the carbon fibre two pack lacquered, can't wait to get back to give it a try.

Peter

http://www.youtube.com/watch?v=eoZmX...eature=mh_lolz

Peter. Maybe you should also say that the capacityproblem is not just an Ilmor/Indy-issue. You have the same problem on the Mercury-drives. Both with the Bravo/ITS and #6-drive.

peterunwin 01-17-2014 03:40 AM

6 Attachment(s)
Thanks 454 captiva & Chuck. Hi Mikko it is fair to say that lack of hydraulic flow is pretty much across the board in marine applications and almost any system can benefit from these modifications, the ilmor drive has larger cylinders for steering than a number 6 so in a single surfacing application that would require even more pressure to steer against the rotation.

Peter


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