Nova Rossi factory break in procedure.
- Thread starter Terry Keeley
- Start date
Help Support Intlwaters:
- Joined
- Jul 24, 2002
- Messages
- 7,126
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:
But their V4 logger doesn't support it, only a "loop" type sensor.
- Joined
- Aug 24, 2005
- Messages
- 339
I have not measured any port changes before or since that date. I would be most interested in discussing those changes and comparing data if anyone is interested.
- Joined
- Jan 2, 2005
- Messages
- 1,048
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. JeffBrass 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.................................
Andy Brown
Well-Known Member
- Joined
- Feb 8, 2003
- Messages
- 2,657
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.
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.
Andy Brown
Well-Known Member
- Joined
- Feb 8, 2003
- Messages
- 2,657
- Joined
- Oct 24, 2002
- Messages
- 4,510
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.
Andy Brown
Well-Known Member
- Joined
- Feb 8, 2003
- Messages
- 2,657
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.
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.
dwilfong
Well-Known Member
- Joined
- Jul 1, 2008
- Messages
- 5,968
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.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:
But their V4 logger doesn't support it, only a "loop" type sensor.
Last edited:
dwilfong
Well-Known Member
- Joined
- Jul 1, 2008
- Messages
- 5,968
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".........
- Joined
- Jan 2, 2005
- Messages
- 1,048
Fire up that dremel , most of us know that new sleeve can be improved . Lol
- Joined
- Apr 13, 2011
- Messages
- 6,347
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.
- Joined
- Apr 13, 2011
- Messages
- 6,347
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.
Marty Davis
Well-Known Member
- Joined
- Sep 25, 2004
- Messages
- 2,445
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.
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.
Andy Brown
Well-Known Member
- Joined
- Feb 8, 2003
- Messages
- 2,657
"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.
- Joined
- Jul 24, 2002
- Messages
- 7,126
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?
Last edited:
Andy Brown
Well-Known Member
- Joined
- Feb 8, 2003
- Messages
- 2,657
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.
- Joined
- Jul 24, 2002
- Messages
- 7,126
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?
Michael Costanzo
Well-Known Member
- Joined
- Jan 7, 2009
- Messages
- 1,953
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.
