Nordicflame

Does anyone have a speedo pitot tube on the back of their stepped Heat?
The Max Machine drive has a reinforcing block that covers the drive pitot hole and the owner really isn't interested in a GPS deal .
Was wondering where to mount one and how well it will work with the step turbulance.

Thanks,
Dave

Linster

I used a graffrig on my velocity, I installed it on the notch, but it was not a stepped bottom. I really dont see it as problem, but it could.

Steve Zuckerman

Dave,
Gps is the answer. The truth shall set the owner free, and he won't have a speed robbing, clogging, bs reading speedo!
Both my boat and my buddies Fountain had water pressure speedos. Both were run off the lower unit. Both are GPSers with recall now.
I think if you mount it outside of the left side of the prop rotation diameter, with an adjustable depth transom bracket, it will work as well as these things do. You might even be able to calibrate it by changing the depth of the pickup. When I used these in the past, we never mounted them on the right side because they could, if mounted too close to the prop, mess up the water flow into a right hand rotation propeller.
Steve

Nordicflame

I'm wondering if I can just extend the existing tube from the out drive over to the mount position.
I would like to mount it up under on the notch front wall but it may be too much in line with the prop water
I don't recall how much that notch spans outward.
Dave

Steve Zuckerman

Dave,
That would be a cleaner installation (under the notch), but I would move it over on the port side of the transom. I think you're going to start a vortex in front of the prop. In the old days of low x dimensions, this probably would not be an issue. But as high as our motors are mounted in the Heats, in a semi-surfacing application, you need to get as much clean water to the prop as possible.
This is the Livorsi I used to use.
Steve
Steve

Nordicflame

Steve,
Livorsi makes a low profile one for mounting on steps. Say's it requires a thru hull fitting but using it on the notch I could run the existing tube to it.
Livorsi p/n GCRB1A.
If you have a notch pic handy it would be helpful.

Thanks,
Dave

Steve Zuckerman

Dave,
This is from my archives. I'll try to get you something better.
Hope this helps.
When are you going to run the Heats???
Regards,
Steve

Nordicflame

Thanks Steve,
By the looks of that I may only be able mount it on the transom just port side of the notch and center between the tailer bunks.
We ran the R-Tech boat on Saturday and have some inconclusive reults so far.

I did a data log on the run and it appears to be using 15% more fuel than the standard setup did. It actually showed more like 20% but the coolant temp of 75* was enriching 4-5%. Bottom line was it was using 520 lbs/hr of fuel

Any way we had the lab 30 prop on there and it crawled into the rev 5850 rev limiter pretty easily and showed 87.4 GPS but was still pulling hard when we pulled out due to rev limit. Although the air temp was only 68 the water was glass. At the rev limiter, we are at a corrected 5.8 lbs(140kPa of the ECU) of boost. The compressor is putting out 8+ lbs but we are starting out 2.5 in the hole at this 4600 foot elevation

When we run to Havasu it will be running the same pulley and actually be seeing over 8 lbs. We are taking a new lab 32 but we are trying to round up a stock 32 to take as well.
The mid 90 numbers last year were achieved with a stock 30 in a good chop at Havasu so I'm thinking the stock 32 may be the answer.
We'll see...
If the wind dies down today I may go test the 750hp Whippled 496HO Heat this afternoon. It will be with out the hatch because after the install nothing fit

Thanks,
Dave