Gas props on nitro rigger

[dwilfong]

Here is a better shot of the P/S.

have you had any issues ripping out the wrist pin boss? i am surprised if you haven't been how close you are cutting it to the piston

Well Had a little set back in testing at the Winter Nat's. First Eng failure.

Pulled the pin bosses out of the piston in round 1 leading the race.

:lol:

YA YA yuck it up. thats racing. the worst part was I had to jump in the retrieve boat and pick it up. :angry:

Who the heck hit me any way.

 

[Buckshot]

The failure that David had was casused a few weeks back. Unless he was doing a inspection after every run he would not have seen it coming.

I disassemble the eng after every run to see what is going on. that is when I found the sag in the piston after testing the pipe on Sat.

I'm not that stupid Chuck.

David

So you took the motor apart after your little incident on Saturday to find the piston had issues only to put it back together to run it on Thursday and expect it to survive?!?

 

[dwilfong]

The failure that David had was casused a few weeks back. Unless he was doing a inspection after every run he would not have seen it coming.

I disassemble the eng after every run to see what is going on. that is when I found the sag in the piston after testing the pipe on Sat.

I'm not that stupid Chuck.

David

So you took the motor apart after your little incident on Saturday to find the piston had issues only to put it back together to run it on Thursday and expect it to survive?!?

Well you do what you got to do to race. no time to break in the new one.

 

[dwilfong]

Well Had a little set back in testing at the Winter Nat's. First Eng failure.

Pulled the pin bosses out of the piston in round 1 leading the race. then got run over and riped the transom out again!

Hurt the piston testing the new pipe on Sat. could not feed the Eng enough fuel and sagged the piston.

Time for a new carb set up.

Have a few design bouncing around in my head :blink: My buddy Dick Jones showed me a carb he had designed that I was thinking about doing. Have had that Simplex -Crane carb bouncing around in my head since I did the rebuild on on one. :mellow:

Kind a scary we where thinking the same. Dick you are a bad influence on me. :lol: Now you showed me how it is done.I won't get any sleep for a month.

But one thing did go right. Can you say MW3 on a X mono. :huh: Yes Dick thats your falt also.

Will keep you all posted on the testing.

David

so you like my MW3?? h34r:

Lost that one the week befor when it spun the prop shaft of the cable.

This was a stock one I had in the box.

 

[BigChuck]

David....what you found on the Saturday was the end result. Did not say you were stupid. What I am saying is :all of the testing, motor in over rev conditions, motor with not enoough load. Motor running full tilt and you kite the boat. All of those factors and the fact that it is a 101 was the cause. I applaud your testing and desire to move forward................learning the areas within the motor that we have and its limits will get you to your goal.

 

[dwilfong]

David....what you found on the Saturday was the end result. Did not say you were stupid. What I am saying is :all of the testing, motor in over rev conditions, motor with not enoough load. Motor running full tilt and you kite the boat. All of those factors and the fact that it is a 101 was the cause. I applaud your testing and desire to move forward................learning the areas within the motor that we have and its limits will get you to your goal.

I am just starting to test the limit of how far it will go. Like I always say. BEAT IT TILL IT BREAKS.

Then you will know what you got.

I will let every one know what happens as it goes on. Hopefully it will get more BIG BLOCKS on the water.

Ain't no fun playing by your self.

David

 

[julianconde]

im here to run with ya if you can keep up lol well i hope i dont grenade my motors when i test these bad azz pipes on my TWIN Roadrunner Extreme

 

[dwilfong]

You will have to swing this if you want to keep up.

 

[scott bouchie]

That thing is a toy,I run this on my A hydro!

 

[dwilfong]

You will have to swing this if you want to keep up.

Dude Clean your shop LOL

Just kidding mate

Greg

When I can't find some thing then I get POed :angry: then I clean the shop. -_-

 

[Buckshot]

That thing is a toy,I run this on my A hydro!

Oh yeah? Well I'm running the prop off our retrieve boat......in heat race trim!

 

[julianconde]

That thing is a toy,I run this on my A hydro!

Oh yeah? Well I'm running the prop off our retrieve boat......in heat race trim!

Ohh Yeah well im using a pair of submarine props on my twin Lol

 

[Ray Sametz]

Hear the props off the Costa Concordia are for sale cheap. :lol:

 

[dwilfong]

Keep it up and I will have mark send me one of the jet ski impellers the guys in Europe are using. :huh:

 

[shoboat]

David,

I have a new option almost ready for you to test next.

I think you will like it.

Rest Up,

Mark Sholund

 

[dwilfong]

David,

I have a new option almost ready for you to test next.

I think you will like it.

Rest Up,

Mark Sholund

I will be ready for the next step soon.

Looks like the gas prop thing is catching on now.

David

 

[Bob Morton]

Been using gas props for some time. (ö¿ö).

Nails

 

[dwilfong]

Well I finely got to down loading the log from the winter nats race.

This is the log from the first heat when the piston let go. Think I need more prop.

This was with the MAC's 13cc pipe at 11 1/2' and 50% nitro.

The prop was a ABC 2717 7.50 T.E. 7.71 C.O.B. at 67.68mm Dia.

David

 

[Jim Caldwell]

David, trim or cut the pre race portion of the graph or look at page 2 and check the average # at the bottom of the graph.

You are dropping a lot of rpm in the corners and your ave. rpm's look low.

My experience (with 7.5 HP electrics) is lower lap times come from easing the turn in to the corner to keep from chocking off the rpm's in the corners and working with props to raise the average rpm's at the bottom of the chart.

 

[dwilfong]

Jim this was in a race. with dead and slow boats to go around. I think I will log throttle position to get a better picture of what is going on for next test .

Testing by yourself and logging in a race are two different beast. when racing you can't always pick the best line. the spikes to top speed mean more. that is the launch off the corners that will keep you up front. lap time don't mean much when in a 6 boat heat. but throttle control dose. giving up some speed in the corners is not bad if it launches like a rocket off the corner from lane 0.

Look at the spikes to top speed from 35 to 80. also look at the relation ship of RPM to speed the spikes are liner. the two graphs fallow each other real nice. this shows the prop is hooking up not spinning its wheels. how you interpret the chart makes a difference in what you see.

David