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Discussion Starter #1
I own a engine shop i have a new superflow 902 dyno ill give free dyno time to anyone willing to bring a motor down and spray it and show me that lean won't hurt it, lets lean it out till it dies see what the piston's look like then post pics online and let everyone tell us it was to fat and thats why it looked like someone got in there with a plasma cutter.

then will put it back together run it as fat as we can till it won't take it take it apart and see what happens.

no more debate lets tare some shit up and prove this myth
 

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Id be willing to throw together a 302 ford with a forged rotating assembly and burn it up. You have an extra set of slugs for a .030 over block? Where ya located? I got alot of spare stuff laying around cant sell it might as well burn it up in the name of science!!:-D
 

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just use stockshortblock 302 stuff (the forged piston stuff) should serve the purpose just fine without tearing up a bunch of expensive parts
 

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I own a engine shop i have a new superflow 902 dyno ill give free dyno time to anyone willing to bring a motor down and spray it and show me that lean won't hurt it, lets lean it out till it dies see what the piston's look like then post pics online and let everyone tell us it was to fat and thats why it looked like someone got in there with a plasma cutter.

then will put it back together run it as fat as we can till it won't take it take it apart and see what happens.

no more debate lets tare some shit up and prove this myth
Tom, can i come play with you with this myth?...lol
I wish i had something laying around!
 

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Chicago's a ride. LOL. Id love to do this lil experiment. It would be fun to burn something up and actually laugh about it for once. :-D
 

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This is not that serious or is it? Isn't the point of all of this conversation is to stop destruction by stating what has caused "shit to happen" in "whatever" particular situation. Tunes hurt shit, failing fuel pumps have hurt shit, bad wiring jobs have hurt shit, loose fuel lines from rushing have burnt shit down, BIG HURT when that happens. A motor doesn't have to be destroyed & it won't settle this debate, because this debate is based on opinion, mostly. A fat tune w/a lean ass carb has lived. A lean tune w/a fat ass carb has lived.

A overtimed motor well now ask guys that have run 18* headed sbc's or other shallow chambered heads about that. How about we focus on that (timing) instead. How many have lifted heads, blown gaskets out, & popped a weak piston from being to aggressive with timing & not running the right fuel. What if it's too much cylinder pressure at the wrong time that screw's everything up, that starts the chain reaction? That's (timing) part of the tune also. Even those that use the lean tune stance have said time & time again they have gotten bit rollin shit back in just a little too much. Clean holes live, dirty holes kills motors form 1.6 SOHC Honda to the latest double throwdown Fulton piece. Us regular guys we break were done for a minute. If you have someone's budget to burn & the OK have at it, it don't matter rich or lean the point then is winning!
 

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Tom,
I would love to come up and play along with you on this one !!!!

I'm sure we coul spend days on the dyno going to the extremes to show guys what happens. Without a doubt you can burn an engine up with to much or to little fuel or timing. Over the last 30+ years of working with nitrous and going to 30 to 40 races a year for the last 12-14 years, I have seen a lot !!! :rolleyes:

Give me a call if you get some time and I have a couple of other ideas to run by you too... Thanks, Steve
 

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Discussion Starter #13
Tom, can i come play with you with this myth?...lol
I wish i had something laying around!
of course jimmy i wouldn't have this much fun without ya!!!

all kidding aside im very aware of how many million other ways to hurt a nitrous motor im only talking the rich/lean debate we will tune it with whatever hp jets get the most power we can back it up a few times then start the destruction from there we will run it rich and lean see which one does more damage and how far we have to get of the beaten path from correct tune each one goes.
 

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Discussion Starter #14
i also have a bet to settle local racer here bet me 1000 that i could not double a engines hp if it makes 500 it won't make 1000 so im also in for proving that im sure Big Steve Induction's can help me with this.
 

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I don't have any method to prove this but from some personal experience destroying some shit on nitrous here is my take and the physics of how this works.

A fuel heavy nitrous motor will leave a fuel heavy build up inside the ring land. Becuase nitrous can be both liquid and gas "mostly gas" in the cylinder its possiable that the nitrous gets down on the wet rings and when 450 or so F temps come up it breaks away from the nitrogen. Being nitrogen is lighter then oxygen the nitrogen moves to the top of the chamber leaving a very oxygen heavy charge with loads of fuel on thh ring land creating a blow torch effect.

Also combustion in the ring land can cuase micro detonation in the ring lands which leads to oil control problems where the ring unsettles and then you have a nice oil filled cylinder.

Also theres been alot of work done in SAE papers on exactly when the conbustion proces starts. Most of these papers point to eh air in the cylinder becoming almost plasma like in energy with the ignition timming acting more like a hysteresys point in the combustion process. when the engine gets really hot and head , piston and valve tempature start to get very high its possiable the the ignition itself almost becomes a moot point and the engine becomes autoignition device. this is where things start to unravel.

If the cylinder gets into a state where it could autoignite "From a myriad a sources and reasons" we are now adding advanced burn into a cylinder with excesive timming lead and this leads to the phenomenon preignition. Detonation might be a problem but preignition will absolutely destroy parts, It can break rods like pretzels and lift off heads with no issue what so ever. It can break blocks,Break Cranks and Bend or snap rods like pretzel sticks.

add some extra fuel to the party and poorly designed head,chamber,piston and now we get into realy trouble in a big hurry.

Given that NO2 is a oxidizing agnet and it breaks down in terms of chemical energy production towards TDC that why nitrous motors do not need loads of timming as there is a readily available oxidizier present in the cylinder to light off the charge quickly and succinctly.

Now if the engine is to lean 2 things can become problematic.

A overly lean mixture will not light

A sligthly overly lean mixture may light and the oxidizer may start to oxidize the aluminum.

All of these scenarios are very plausiable and fit neatly inside of most chemistry and observed combustion studys done to date.

YMMV.



This is not that serious or is it? Isn't the point of all of this conversation is to stop destruction by stating what has caused "shit to happen" in "whatever" particular situation. Tunes hurt shit, failing fuel pumps have hurt shit, bad wiring jobs have hurt shit, loose fuel lines from rushing have burnt shit down, BIG HURT when that happens. A motor doesn't have to be destroyed & it won't settle this debate, because this debate is based on opinion, mostly. A fat tune w/a lean ass carb has lived. A lean tune w/a fat ass carb has lived.

A overtimed motor well now ask guys that have run 18* headed sbc's or other shallow chambered heads about that. How about we focus on that (timing) instead. How many have lifted heads, blown gaskets out, & popped a weak piston from being to aggressive with timing & not running the right fuel. What if it's too much cylinder pressure at the wrong time that screw's everything up, that starts the chain reaction? That's (timing) part of the tune also. Even those that use the lean tune stance have said time & time again they have gotten bit rollin shit back in just a little too much. Clean holes live, dirty holes kills motors form 1.6 SOHC Honda to the latest double throwdown Fulton piece. Us regular guys we break were done for a minute. If you have someone's budget to burn & the OK have at it, it don't matter rich or lean the point then is winning!
 

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Discussion Starter #16
I don't have any method to prove this but from some personal experience destroying some shit on nitrous here is my take and the physics of how this works.

A fuel heavy nitrous motor will leave a fuel heavy build up inside the ring land. Becuase nitrous can be both liquid and gas "mostly gas" in the cylinder its possiable that the nitrous gets down on the wet rings and when 450 or so F temps come up it breaks away from the nitrogen. Being nitrogen is lighter then oxygen the nitrogen moves to the top of the chamber leaving a very oxygen heavy charge with loads of fuel on thh ring land creating a blow torch effect.

Also combustion in the ring land can cuase micro detonation in the ring lands which leads to oil control problems where the ring unsettles and then you have a nice oil filled cylinder.

Also theres been alot of work done in SAE papers on exactly when the conbustion proces starts.

Given the NO2 is a oxidizing agnet and it breaks down in terms of chemical energy production towards TDC that why nitrous motors do not need loads of timming as there is a readily available oxidizier present in the cylinder to light off the charge quickly and succinctly.

Now if the engine is to lean 2 things can become problematic.

A overly lean mixture will not light

A sligthly overly lean mixture may light and the oxidizer may start to oxidize the aluminum.

All of these scenarios are very plausiable and fit neatly inside of most chemistry and observed combustion studys done to date.

YMMV.
explaine to me how much alky sprint car guys that don't have a nitrous kit on them burn piston's the same way running lean.
 

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This would be a great Idea. Spraying large amounts of nitrous on a engine dyno. Can we start the pull round 3000 rpm?
 

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Discussion Starter #18
This would be a great Idea. Spraying large amounts of nitrous on a engine dyno. Can we start the pull round 3000 rpm?

sure why not do it all the time what if motor made peak power at 5500 like say a stock 302 we were talking about what ya going to start the pull at 5500 that is all relative to the engine in question.
 

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a under fueled alky motor tends to generate alot of heat. without seeing the parts in question "I'll be dead honest here" its a tough question to answer. It could be that running lean on alky will really create alot of oil consumption which ultimate lowers the fuels resistance to detonation. It could be the running lean on alky "a self oxidizeded fuel" could setup a situation wherein the motor itslef turn into a igntion source. alky has a very low tempature vaporization point and if there was a lack of cooling it could begin a preignition cycle using the exhuast valve as a ignition source.

There a 1000 ways this situation could occur from a physics stand point. Without parts its tough to say.

usually if you burn the edge of a piston you have 2 common problems. Oil control issues or poor piston design creating a thermal hot spot. coupled with a lean tune up this could be the issue.

tough call. I am simply presneting the physics in as short hand a form as I can.


explaine to me how much alky sprint car guys that don't have a nitrous kit on them burn piston's the same way running lean.
 

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How many people on the bullet have engine dynoed a race motor with a big hit?
 
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