Nova Rossi factory break in procedure.

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If you can fit the thermal couple between the head and the case.. near the liner.. that would be a good place to try.

Grim

That would work too but was thinking more around the glow plug, seems where the car guys are always checking.

Eagle tree had a sensor for their earlier logger & Mike Rappold here took advantage of it:

full


But their V4 logger doesn't support it, only a "loop" type sensor.
 
Brass head button and small custom cooling caps work killer.
Noting like a "hot head" to burn NITRO.
Get the water off the case the fuel will cool it enough.

Could not help my self Eric now could I....LOL
Back lash baby back lash.................................:p:D
David, I’m not sure what angle you are pulling from or why , I’m sure your just having some fun. Many boaters have changed port areas and angles over the years. Especially on standard 3 port setups. Cmb had appropriate sized transfers on some of their older big blocks. They did shrink down the sizes on the RS series, although it wasn’t clear why. We did express to the powers that be that we were opening the ports up, and we always hoped they would head back that way. The most important thing here is that they are much different now on the new Evo series and they are improved. I picked up a new 2019 RS EVO 101 from Stu in January. It has a new style transfer that is like the M1 91 , I’m not sure why this isn’t advertised, but the port area is pretty darn good right out of the box. Just thought I would point out Cmb does have a new port design, and its larger also in case you didn’t know. Jeff
 
Rod Geraghty mentioned something about racing with low nitro.
Jason Brown placed 4th at the Fall Nats in F Hydro on a mixture of ZERO % Nitro and 15% castor. His speed was competitive and he would have placed better if not for hitting a buoy in one heat.
 
Yes the Dremal mod fixed a lot of problematic CMBs (and Piccos, Novas, others).

Geraghty, there are many times when a manufacturer does not produce a perfect product and “dremel mods” actually lead to much fewer parts failures. A great example of this was when everyone was melting holes in RS 1.01 pistons. Jeff saw clearly that the transfers in the engine were too small and opened up the crankcase passages and the ports in the sleeve. After the manufacturer saw what these “dremel mods” did to improve the engine, they copied it and now all the engines come this way from the factory.
 
If you can fit the thermal couple between the head and the case.. near the liner.. that would be a good place to try.

Grim
OK now that we have the telemetry heat sensors to use, what would be a good operating temp for the case between the fins and at the head near glow plug??
I have used a temp sensor on novi 21 at the case fin and it read 150 - 170 running fast just leaned out a bit.
 
Yes, the engines are the same. BUT cars and boats need different power curves. 39,000 from a stock 21 on 20% nitro will push an On-road car to 70 mph.
The same engine set up in a heat race rigger would never see 39,000 unless a small prop is used, but then the boat would not see 70 mph on that prop.
This, because the HP is long gone at 39,000. The on road car does not need as much HP to reach 70 as the boat does.

The peak HP will be around 32,000 and peak torque around 25,000 on stock engine with 20% nitro.

The boat needs peak power at top speed. Boats can not use "over-rev" as an On road car can.
Therefore the engine in the boat will hit top speed at about 32,000 rpm. The only way to get the same top speed at 39,000 is to set up the engine to make the same (or more) peak power at 39,000. That would require modification....and possibly the work of a Dremal!

I tested the MAC 21 Buggy engine to 45,000 rpm. The car hit big speed at that rpm. The same engine actually ran the same speed in a microBurst mono, but the engine rpm was 33,000. Right on the peak power.
 
That would work too but was thinking more around the glow plug, seems where the car guys are always checking.

Eagle tree had a sensor for their earlier logger & Mike Rappold here took advantage of it:

full


But their V4 logger doesn't support it, only a "loop" type sensor.
You can get any thermal resistor with the same resistance and use it . It is just a wire end with a resistor held in with heat shrink. Check it with a meter and get one off Ebay.
 
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David, I’m not sure what angle you are pulling from or why , I’m sure your just having some fun. Many boaters have changed port areas and angles over the years. Especially on standard 3 port setups. Cmb had appropriate sized transfers on some of their older big blocks. They did shrink down the sizes on the RS series, although it wasn’t clear why. We did express to the powers that be that we were opening the ports up, and we always hoped they would head back that way. The most important thing here is that they are much different now on the new Evo series and they are improved. I picked up a new 2019 RS EVO 101 from Stu in January. It has a new style transfer that is like the M1 91 , I’m not sure why this isn’t advertised, but the port area is pretty darn good right out of the box. Just thought I would point out Cmb does have a new port design, and its larger also in case you didn’t know. Jeff
Yes just having a little fun with my buddy ........ no angle ..........
I have the newest 1.01 EVO P/S set up ......... It's OK........ Still like the big port/case set up that you came up with for top power on high nitro.
Need room for all that "FUEL" to flow threw the case. Buggy and aero engines with small high velocity runners and ports designed to run on low or no nitro can not flow all that "FUEL".........
 
Yes just having a little fun with my buddy ........ no angle ..........
I have the newest 1.01 EVO P/S set up ......... It's OK........ Still like the big port/case set up that you came up with for top power on high nitro.
Need room for all that "FUEL" to flow threw the case. Buggy and aero engines with small high velocity runners and ports designed to run on low or no nitro can not flow all that "FUEL".........
Fire up that dremel , most of us know that new sleeve can be improved . Lol
 
Rod put me on tho this. 39+K at 320F for 10 mins! Then another gallon in the car until it's at it's peak.


Great video to post Terry. Thank you for sharing it with everyone. Its incredible to watch how they do this in the factory. The out of box performance for the average boater Nova achieves is second to none. Jeff Lutz is also correct, those with the knowledge and means can get even more out of their engines if looking for certain areas of improvement, more rpm less torque or more torque, less rpm. Nova puts you at the midpoint of both, and to Carl’s point, gives you more time with setup and in his case, one of the fastest heat racing outboards around. Great conversations guys.
 
Here is the break-in stand Mike Brevoort built for breaking in Nova engines for customers. He simply uses a cut-down pusher prop in different sizes for 12-91’s. It works great. He monitors temps at glow plug to get them up to and keep at around 200 degrees for whatever rpm he is running. He has a variable speed dialysis pump he uses to vary the water flow to achieve the proper temps. His process works great to get the engines out of the “squeaky pinch” stage and closer to race ready. Only minimal break-in left when received by the customer.
 
I run the Nova Rossi 21 DD and I run it stock with only head clearance changed.
I sometimes change the carb just to test which ones run the best on the water.
The pipe is also a huge part of the engine running well with our application.
 
Great video to post Terry. Thank you for sharing it with everyone. Its incredible to watch how they do this in the factory. The out of box performance for the average boater Nova achieves is second to none. Jeff Lutz is also correct, those with the knowledge and means can get even more out of their engines if looking for certain areas of improvement, more rpm less torque or more torque, less rpm. Nova puts you at the midpoint of both, and to Carl’s point, gives you more time with setup and in his case, one of the fastest heat racing outboards around. Great conversations guys.

"more rpm less torque or more torque, less rpm. Nova puts you at the midpoint of both,"


There is also the more RPM, more Torque approach. It equates to MORE HP. I prefer to use that program.
 
The boat needs peak power at top speed. Boats can not use "over-rev" as an On road car can.
Therefore the engine in the boat will hit top speed at about 32,000 rpm. The only way to get the same top speed at 39,000 is to set up the engine to make the same (or more) peak power at 39,000. That would require modification....and possibly the work of a Dremal!

Trying to understand this. You say the boat won't go any faster than at the rpm it makes peak HP? Because of prop slippage?

If it revs say a couple thou past peak HP but still makes useful torque won't the boat go faster?
 
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Trying to understand this. You say the boat won't go any faster than atn the rpm it makes peak HP? Because of prop slippage?

If it revs say a couple thou past peak but still makes useful torque won't the boat go faster?

Hi Terry, Hope you are doing great!
Dynamic drag increases with speed. Boats, airplanes, and Bonneville cars are the same in this respect.
The faster they go, the more Horsepower they require.

Road race type cars need max HP to accelerate mass out of corners. Once the major acceleration has been overcome, lower HP over-rev is enough to gain extra top end speed because dynamic drag of the car is less than the force of high rate acceleration of the mass.
 
Hi Terry, Hope you are doing great!
Dynamic drag increases with speed. Boats, airplanes, and Bonneville cars are the same in this respect.
The faster they go, the more Horsepower they require.

Road race type cars need max HP to accelerate mass out of corners. Once the major acceleration has been overcome, lower HP over-rev is enough to gain extra top end speed because dynamic drag of the car is less than the force of high rate acceleration of the mass.

Doing good thanks, hope ya'll are too!

But wouldn't a light weight, smooth running hydro be similar? In other words absorb a bunch of HP to get up on plane and up to speed then need very little to go faster from there?
 
Do whatever you like .......I am happy for you that you have been successful with your approach to RC nitro boating....
All I said is there is RPM in a "stock" motor we have never touched.....
I am sure Novarossi loves your approach to motor and set-up tuning.....they make new parts every day....
Rod, have raced very high end N/R car engines(.12's & .21's) On-Road & Off-Road for over 25 years and NONE of them were STOCK!! those motor's that go to" Factory Drivers" are NOT STOCK!! My engine guy is "Uhriah Muran" from Austell,Ga ( look him up,anyone that competes at National level know's of him. and he is one of N/R Team Engine's big competitors and he has been inside some of those "Stock" motors and he will tell you the same thing,not stock.timing,bowl,crank! also have raced "JP Racing,Ron Paris,and a few other well known guy's and they will all tell you the same thing,you will Never get the same RPM's from a stock engine,no matter what pipe, fuel,ETC as modded motors.
 

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