NR Hybrid engine

[anthony_marquart]

Guys,.

Finnaly got the NR hybrid to a state I would consider it broken in.. Problem is speed. Here's the set up.

JAE style hull,.. proven,, works great

NR Hybrid

S pipe at 3 in

66% torco

Odonnel medium cold and cold plugs

H7 by Sholund,.

0.050 water outlet in the cooling head.. should be warm enough..

Here the thing.. top speed 64 MPH,.. when i ran the 5P. Same set up,.. motor was older,.. I got 70,.. all day..

What do I need to set up differently to get back up there.. This is supposed to be a better engine.. and don't get me wrong.. it runs well,.. slows down,.. jumps back up.. great control.. Just not seeing the speed I did in the 5P.

Maybe it's just that the 5P was better fro my particular set up?

 

[anthony_marquart]

Are you running the S pipe? RPM seems good..

Any other guys see less torque with the Hybrid? Prop is not really that big...

 

[anthony_marquart]

Seems like a burn through the hot plugs.. pretty fast..

 

[anthony_marquart]

I think its a very different animan,.. Glenn can comment,.

What speeds are you seeing?

 

[anthony_marquart]

what prop and pitch you running? I really think I should be able to get there with this setup also..

 

[RodneyPierce]

I can be the first to say that mid 70's is NOT easy to achieve (for me anyways, and a few others I know that have touched low 70's). There are so many internet racers that "think" there boat is in the 70's, and if they ever got it on a Stalker they would probably ****.

Anthony, whats the diameter and pitch on the H7??

 

[anthony_marquart]

I'll have to look at the numbers when I get home..

But in the 5p, I had it on radar, stalker, at 70 consistent. and yes is was not easy but when I found the pipe, pipe length, prop combo,. it was consistent.

I'm wondering if I need to run even less water.. try to run hot and fat..

 

[gooycheese]

I see maybe 3 or 4 70+mph boats a year at races... anthony bring your boats to race... lets see it

20 hydros that is

 

[Jeff Schindler]

I'll have to look at the numbers when I get home..

But in the 5p, I had it on radar, stalker, at 70 consistent. and yes is was not easy but when I found the pipe, pipe length, prop combo,. it was consistent.

I'm wondering if I need to run even less water.. try to run hot and fat..

Anthony, Its hot and rich. Hot and Fat don't go together

 

[anthony_marquart]

Hey Paul,,, I really hope to get to some formal races.. we;ve got a small but growing club here in Charlotte where I live now..

I'm not exaggerating the numbers.. all data taken on radar guns..

You guys that are going fast with the S pipe,.. what length are you running,.. I'm right at 3 from center back, which is really like 8in.. I've had trouble running is shorter.. what would you suggest?

 

[Paul Traufler]

What deck clearance do you have? .006" would be in order, below .009" for sure.

 

[anthony_marquart]

0.006, set by Glen..

 

[shoboat]

Tony,

Get a new 5-port.

Just my thoughts,

Mark

 

[anthony_marquart]

Well,, this motor has yet to eat a plug,.. still that new.. I'll try a bit more.. and if it doesn't work for my setup someone else can try it on theirs.. and Ill go back to the 5p

 

[steve wood]

what are your crank numbers, what are your sleeve numbers(transfers,exhaust ,blowdown), what head volume(brass or aluminum button), what head clearance. stock water jacket is too large. what's been done to the sleeve. pipe is too long. address these and you will start seeing 72, then 75, then 80 mph with the right boat and prop

 

[anthony_marquart]

Steve, the motor is stock except for the reduced volume done by Glenn,.. to I want to say .17 volume. Head clearance at 0.006. Also the carb has the spray bar cut back and low end needle removed. I don't know the timing on the motor. Sleeve is stock. water outlet restricted to 0.050 in the cooling head,, plugged the outlet and drilled the hole. Aluminum head button.

Sounds like I need to reduce the pipe length for sure. Do you have the brass head buttons that have the correct volume and height?

Does the Brass head button do anything for me? hold hear better? keeping the engine fat,. I do think this can be done without real dangerous lean runs.. it's clearing out well though..

 

[steve wood]

those carb mods won't make it faster,just more user friendly.fix the crank timing,fix the sleeve timing.aluminum button at .19 cc, brass button .17 to .18 = more torque = shorter pipe = more rpm.brass doesn't detonate like aluminum. shoot for 30° blowdown,127 to 130 transfer,if the transfers are higher than 130, lower the sleeve.close crank at 65°,total about 215°.i use .040 water outlet on small water jacket,with cut down fins. if you don't know the timing,you better learn how if you want to go fast. this is what it takes to get to the next level.when you lean another click and that s pipe second stages,you will know you are on the right path!

 

[Mike Larson]

Anthony 7 7/8ths for me... the S HAS to spin up... and the propellor is it... work there man... Mike

 

[Rene Danner]

I am at 7/78ths for me also,But that is with a 5 port..

 

[acaptn]

Anthony I run the hybrid with an s pipe Orlic button and water jacket .006 head clearance. I am in the 70+ mph range with plenty of torque, it pulls a1452 with no problem. I race with 1450s. Vid on youtube was a stock1452. Bet was it would not pull it!