NR Hybrid engine

[anthony_marquart]

Got some more run time in today. I suppose I'm still babying the motor a bit. Really trying to stick to the method of running lots of fuel and restricting the water to as little as possible. Today I shortened the pipe 1/8 to 2 and 7/8. It's a different type of setup up for me. It's very Rich on the stand. Have to blip the throttle a lot to to keep it from possibly stalling. But after a half lap or so it does not act too rich at all. Seems once it gets hot it burns the fuel just fine. I didn't have radar today but I do think there was progress. I'll probably get this one to 70 eventually. I can say this about the hybrid,, it's not a real finicky or twitchy motor. It launches every time and in the gallon or so fuel I've put through it it has yet to die on the water. Infact its yet to burn a plug. Maybe that is part of the heat and fuel method I'm working on,.. Heat, fuel and pipe as short as I can run it.

What do you guys think of that theory?

 

[anthony_marquart]

I have restricted the water enough that it's coming back pretty warm. Not blazing,.. I think it could be hotter. There is still a decent spray of water coming from the outlet,.. I think if I can get it to run high 60s in most 21 rigger races I'll be doing just fine. I was able to noticeably see the change in performance when I cut the water back again. It took less time to get on the on the pipe. I'm learning the tuning with water flow has a big impact,.. at least from what i can see right now.. I don't want to start eating plugs, messing up the head, running plug coils through the motor. If I can get this thing to run fast rich, and hot, and get 70 MPH.. I think the motor will last a lot longer. All this is just me playing with my hobby and trying a different approach. Typically I would run more water and lean down to get hot.. Is it true that it's easier to burn all the fuel when the engine is hot? Glenn mentioned he saw NR running in motors at I think 300F,.. I'n not where near that hot.. but I want to get to where I can run relatively rich and about 250F...

anyone else have any thoughts on this? been there tried that?

 

[anthony_marquart]

yeah,.. it's just about there,.. it's amazing how much you have to restrict the water in the NR21

 

[LarryConrad]

I have the water restricted in all my .21's. Mac's, CMB's, OS's and Novarossi's. Run them rich with hot plugs on high nitro. If you are running less than 60% in a piped .21 you're just chasing your tail.

 

[gooycheese]

One of the best 21 riggers in D4 runs on 50% grimracer fuel... ohhh and 10 or more thousands for a squish.

 

[LarryConrad]

Consistency and driving skill, Gooy, the fastest doesn't necessarily make you the best. Most of the posts in this thread are focused on obtaining +70 mph performance out on the course, and if the boat you mention is achieving it on 50% and cavernous head clearances, I want to see proof.... 'Cause my nitro supply will go a lot farther mixing 50% than it does mixing 60 and 70.%

 

[SayMikey]

I have a hybrid nova in my Blackbird g2,yesterday while testing for Hobart I put the s-pipe on. Its a monster but going to take a lot of prop work to get consistent runs. It did stage one time and boy did it go,ive never heard my 21 Nova spool up those rpms,I was ready to toss it to the lake gods but next Spring will make that puppy work. For now its a 3280 for a launch and return every time..

 

[LarryConrad]

Say! Mikey! Post up some pics of that G2, I'd like to how it looks with paint.

 

[eekern]

Which s pipe are you guys referring to? Muffled?

 

[LarryConrad]

Irwin/Cooper/Wood S pipe. When are you going to be in Eagan testing next Eric? I have one you can try out if you want.

Larry

 

[anthony_marquart]

I am running 66% nitro.. going to try some hotter plugs soon..

 

[anthony_marquart]

also,.. I have yet to have the boat not launch or return,.. well other than when I flipped in a sharp corner.,.

 

[dwilfong]

You know I listen to this and think to my self.

Every one want the best of both worlds a fast boat and long eng life.

If you are making serious power and pulling big props you will not have both.

Run that eng hot as you can. squeeze the head down till it touches the piston and back off .001 also run high CR 10-1 or more.

The tight clearance and high CR will help with the launch.

This along with the high temp will burn the 65% nitro.

The eng will deto with out a drought but that is the trade off.

Using a brass head button will help keep the temp in the chamber and also save the head when it detos.

The sacrifice is the piston. it will take the brunt of the punishment.

A combo of high CR and lower ex timing will let you run the pipe shorter.

You can't have your cake and eat it too.

Just my 2 cents for what it is worth.

Flack jacket on let here rip.

 

[anthony_marquart]

Hey David,.. I definitely am listening to you. Half the fun of this was working with one of the old timers at the lake that had never restricted water,.. He probably thought I wouldn't get 2 laps in.. You should have seen the look on his face when I was breaking in the motor with NO water running in it.!!! He's a great guy though..

I'm not really looking for a 80mph 21 boat., can't really drive that.. I just want to have a consistent 70 mph boat that I can keep the engine together for a for a few years,.. I'm probably going to have my little boat worn out before I get there..

One thing I'm doing is going back and block sanding my sponson bottoms. it's amazing how lumpy they get with paint! building a new setup board.. having the small but growing club here is really nice.. too bad I'm the only one running nitro.. fortunately none of them have a FE boat that can beat me yet... but it's coming.. soon as they build a rigger I'm cooked..

 

[RodneyPierce]

Not true......P Spec riggers arent all that fast Anthony....you may be surprised...... Just depends on what they build for an FE rigger.