Company to break-in engine and dyno?

[DerekB]

IF there aren't any rule then the engine with the most power will help pull through the gearing. HP will get you a higher topspeed, but most engines that are race oriented pull about 40-45K and some less. An on-road .21 will be the best choice since they do produce more HP and TQ but they won't fit into the car well.

I was at RCCA when they did the 100mph Super nitro RS4 and they had to have special gearing made to get close to that. Pulleys and belts. I'm assuming you're running stock or just a huge pinion?

I just hate to see you waste $650. Buy the OS and it will have more HP and TQ than the .12.

 

[kwong2001]

I haven't decided for gearing, I dunno if i'll get new pulleys for the drivetrain and run stock primary gears, or just get different primary gears made. I know i'll have better gear tuning if I just change the drivetrain. But i'm unsure about running a plastic spur gear. Plus I don't wanna spend $200-300 on gears. Might end up just getting two sets of primary gears made. If I do, it'll be like a .9 something primary ratio.

If I was on a tighter budget, i'd probably just run a hand modified 18TZ in my ntc3 and just do custom primary gears. But I wanna go all out.

I bought the RS4 2 originally to drop a Wasp 28 and make it a basher. But I found out about the contest. I don't think i'll have any problems fitting the engine, there's a lot of room, and wolf pack radicals has already done it.

Also, dunno how big of an area i'll have to do the run, which is another reason why i'd rather run a .21 instead of a small block. Running the single speed, it'll take awhile to get up to speed.

 

[bigfreak]

Hey man, I know you don't know and that's the problem. THere are real dynos. Please visit www.rc411.com and click on the "GOT HORSEPOWER" video to see on in action.

The $10,000 Land and Sea RC dyno (which ALSO uses electrical resistence) can only dyno .12 sized engines. I read your nitro engine round up and I noticed you were only doing .12 sized engines. I don't have enough information to make anything more than an assumption, but I would guess that your dyno is in the same boat as the Land and Sea dyno (.12 only)?

EDIT: I also heard that the Land and Sea dyno has to be calibrated after every dyno run? As in sent back to the factory?? I heard it was due to the nature of how the data is collected (electrical resistence).

 

[kwong2001]

The $10,000 Land and Sea RC dyno (which ALSO uses electrical resistence) can only dyno .12 sized engines. I read your nitro engine round up and I noticed you were only doing .12 sized engines. I don't have enough information to make anything more than an assumption, but I would guess that your dyno is in the same boat as the Land and Sea dyno (.12 only)?

EDIT: I also heard that the Land and Sea dyno has to be calibrated after every dyno run? As in sent back to the factory?? I heard it was due to the nature of how the data is collected (electrical resistence).

I wouldn't assume that. He already stated it can handle a .21. And from the sounds of it, XRC has one of the best dynos for r/c engines.

If you were local in Socal I'd say we'd help you break the engine in and run it on the dyno (although our March issue just did a test with the RB V12 modified) so you can see the graph. And also lots of dynos print out a little "jagged' because that's real.

 

[DerekB]

The $10,000 Land and Sea RC dyno (which ALSO uses electrical resistence) can only dyno .12 sized engines. I read your nitro engine round up and I noticed you were only doing .12 sized engines. I don't have enough information to make anything more than an assumption, but I would guess that your dyno is in the same boat as the Land and Sea dyno (.12 only)?

EDIT: I also heard that the Land and Sea dyno has to be calibrated after every dyno run? As in sent back to the factory?? I heard it was due to the nature of how the data is collected (electrical resistence).

The Land and Sea dyno is the one RCCA had them make that never worked right. It's an eddie current dyno which puts the engine under load to stabilize the readings, but what that does is put the engine under peak TQ and hold. Our engines were not designed to sustain peak TQ conditions. So while the graph may look a little better it effectively will wear out the engine. We've put engines on our interia dyno for over 80-runs and the engine still puts out power (obviously less than peak).

We did .12s first because it actually takes a lot of time to get all the engines, break them in the same way, and get them set up on the dyno. We've tested .21 and .28 and the guy that designed our dyno is a Factory Honda mechanic that works on 2-strokes and 4-strokes for a living.

I'm not saying that dynos are complicated (they are simple) it's just having one with the software.

I'll again point out if these "other dynos" worked why have you NEVER seen them in action? We had our working and shown as fast as possible. Also since we've sold dynos to 10 companies (engine and chassis) and others' are waiting for the next batch to be finished, it's not hard to see which dyno the industry has put it's faith into.

 

[bigfreak]

Thanks for taking the time to explain your system. It sounds like you guys understand the problems and have found a good way to do it. You've also cleared my mind of worries that you might be using the same system RCCA supposidly does. I hope you guys do well selling it.

From a consumer's point of view, I personally would REALLY REALLY love to see another engine round up, but this time .21 style. Hell, even if you broke it up into a handful of issues of the mag, I'd be riding on the edge of my seat to find out how the popular buggy racing engines all stack up: P5, ws7ii, vspec, Rody C5, Nova 421B

I was a little depressed when I saw all the .12 engines and figured maybe you were limited to that size. It sounds like you guys have conquered that limitation. Congrats

Again, thanks for clearing it up for me.

EDIT: KWong, sorry for jacking your thread man. Good luck on your project car.

 

[kwong2001]

The Land and Sea dyno is the one RCCA had them make that never worked right. It's an eddie current dyno which puts the engine under load to stabilize the readings, but what that does is put the engine under peak TQ and hold. Our engines were not designed to sustain peak TQ conditions. So while the graph may look a little better it effectively will wear out the engine. We've put engines on our interia dyno for over 80-runs and the engine still puts out power (obviously less than peak).

What's the difference between intertia dynos and just a dyno that puts it under load? Sorry, I feel like a n00b.

Also, how does that compare to chassis dynos for 1:1 cars?

EDIT: KWong, sorry for jacking your thread man. Good luck on your project car.

No worries, the thread already served it's purpose a long time ago

 

[DerekB]

What's the difference between intertia dynos and just a dyno that puts it under load? Sorry, I feel like a n00b.

Also, how does that compare to chassis dynos for 1:1 cars?



No worries, the thread already served it's purpose a long time ago

There's a slight difference because we are measuring the engine and most real car dynos measure HP at the wheels. It's much easier to do that since imagine taking out an engine everytime. But it estimates how much is lost in the drivetrain and assumes that the engine is putting out what the OEM spec was.

Our dyno uses the same software (re-written by the manufacturer for our application).

An interia dyno is a mass (know and very precise) and rotating that mass. This is a simple way to calculate HP (which is mass over time).

An Eddie Current uses something to hold the engine at a certian RPM to let the reading stablize. Like an eletromagnet. This will offer a better graph but in our application our engine would sanp if held at peak TQ at any length of time. For instance Honda bike engines are tested by holding themat peak TQ for 40 hours. Then they feel it will be ready for public use.

Dynos are very simple. Our software is very complicated.

 

[kwong2001]

There's a slight difference because we are measuring the engine and most real car dynos measure HP at the wheels. It's much easier to do that since imagine taking out an engine everytime. But it estimates how much is lost in the drivetrain and assumes that the engine is putting out what the OEM spec was.

Our dyno uses the same software (re-written by the manufacturer for our application).

An interia dyno is a mass (know and very precise) and rotating that mass. This is a simple way to calculate HP (which is mass over time).

An Eddie Current uses something to hold the engine at a certian RPM to let the reading stablize. Like an eletromagnet. This will offer a better graph but in our application our engine would sanp if held at peak TQ at any length of time. For instance Honda bike engines are tested by holding themat peak TQ for 40 hours. Then they feel it will be ready for public use.

Dynos are very simple. Our software is very complicated.

Hmmm, I understand the x-dyno but i'm still a little confused about the Eddie Current. So on they hold the engine at a certain rpm to calculate the load, then do the run? This stuff is a little beyond my capacity...lol

Also, I picked up the March issue today after coming home from school. On your dyno, I noticed the setup looks pretty similiar to a standard r/c car, in that you have the normal primary gears, except power goes to the big mass. Is the reading taken on the mass? Is it a real-time reading, or an averaged thing like the way a VSM gets it's reading with a single magnet? Also, when doing a big block, is procedure any different? Like changing the primary gears or the mass?

For the tank, I noticed it's a standard setup, why wouldn't you have a fuel pump that keeps tank pressure constant? That would help keep the reading more accurate by minimizing any risk to running lean and getting an inaccurate reading. Or are you trying to mimic racing conditions?

 

[DerekB]

Hmmm, I understand the x-dyno but i'm still a little confused about the Eddie Current. So on they hold the engine at a certain rpm to calculate the load, then do the run? This stuff is a little beyond my capacity...lol

Also, I picked up the March issue today after coming home from school. On your dyno, I noticed the setup looks pretty similiar to a standard r/c car, in that you have the normal primary gears, except power goes to the big mass. Is the reading taken on the mass? Is it a real-time reading, or an averaged thing like the way a VSM gets it's reading with a single magnet? Also, when doing a big block, is procedure any different? Like changing the primary gears or the mass?

For the tank, I noticed it's a standard setup, why wouldn't you have a fuel pump that keeps tank pressure constant? That would help keep the reading more accurate by minimizing any risk to running lean and getting an inaccurate reading. Or are you trying to mimic racing conditions?

An eddie current dyno will hold the engine at a certain RPM to let the reading stabilize. Think Break Horsepower, there's actually a break put on the engine to accomplish the same thing.

The gear reduction is to reduce the time of the run and also keep the mass from spinning at the RPM of the engine. If you could imagine a heavy weight spinning at the speed you approach critical speeds for the material just to fall apart. It's a gear reduction, just like gears in a real car, and the software adjust for the ratio. We aim for a 10 second pull and so a .21 the gearing gets changed to account for the TQ difference.

Fuel pumps aren't used so why use them on a dyno. The engine is running in it's natural state there's no need for a fuel pump.


There is a sensor on the reduction side of the dyno so it's spinning again at a slower speed. It's real time and you can watch the performance of the engine on screen

 

[kwong2001]

So on the Eddie Current, the load is a constant load that wouldn't change, but your x-dyno is more of a linear load?

One of the reasons why I mentioned a fuel pump is because the .12 engines dyno tests, it was stated you used the same kind of fuel, glow plug, and exhaust even though it might not be the most realistic since each engine might require slightly different ones for optimal performance. You wanted to keep control of the variables to just test the engine itself. Kinda makes sense to run a fuel pump since running a normal tank could be an added variable.

 

[DerekB]

So on the Eddie Current, the load is a constant load that wouldn't change, but your x-dyno is more of a linear load?

One of the reasons why I mentioned a fuel pump is because the .12 engines dyno tests, it was stated you used the same kind of fuel, glow plug, and exhaust even though it might not be the most realistic since each engine might require slightly different ones for optimal performance. You wanted to keep control of the variables to just test the engine itself. Kinda makes sense to run a fuel pump since running a normal tank could be an added variable.

As a standard all engines of a group will be test with the samestuff. Wedo several passes until we see a drop in performance (leaner/richer). The glow plug is the one that comes with the engine or if we decide all the same plug. Fuel pump won't do anything really. There's no "rule" to what an engine will produce since each is different. In real cars there's no fuel differences, or stuff like that. Manufacturers supply the exhaust for real cars. THere are 8 million different combinations of pipes, plugs, fuel, oil, header length, and more to start to try and make the most power.

Then there are the poeple that are obessed with peak hp and forget the area under the graph is more important.

 

[Plaidfish]

How long does it take for you to set up an engine/pipe/gear setup to run on the Dyno?
what is the average cost of each run? ie cost of just running the dyno equipment, not including the engines and pipes.....I'm just wondering why not try different combos for that peak performance set upif you already get a pipe from manufacturers A B C & D and Engines from manufacturers X Y Z why no try mixing the combos and see which engine runs best w/ which pipe? I understand if it takes a long time to do this but why not do one set a week?

 

[kwong2001]

As a standard all engines of a group will be test with the samestuff. Wedo several passes until we see a drop in performance (leaner/richer). The glow plug is the one that comes with the engine or if we decide all the same plug. Fuel pump won't do anything really. There's no "rule" to what an engine will produce since each is different. In real cars there's no fuel differences, or stuff like that. Manufacturers supply the exhaust for real cars. THere are 8 million different combinations of pipes, plugs, fuel, oil, header length, and more to start to try and make the most power.

Then there are the poeple that are obessed with peak hp and forget the area under the graph is more important.

Well engines do lean out as the fuel is used. But for a short 10 second run, it won't make a difference.

One question, on the engine tests, the horsepower ratings were totally different form what i've seen from any other. To keep things in perspective, have you done any dynoes with sport engines like say a 12cv-r? Also, have you done any big block dynos? If so, what kind of engine was it and how much did it make?

 

[DerekB]

How long does it take for you to set up an engine/pipe/gear setup to run on the Dyno?
what is the average cost of each run? ie cost of just running the dyno equipment, not including the engines and pipes.....I'm just wondering why not try different combos for that peak performance set upif you already get a pipe from manufacturers A B C & D and Engines from manufacturers X Y Z why no try mixing the combos and see which engine runs best w/ which pipe? I understand if it takes a long time to do this but why not do one set a week?

There is no perfect setup. If there was I'd assume that teh manufacturer would have that info.I'd love to have the time to sit with one engine for a week and run the engine til death, but list the amount of pipes, fuel, shims, headers, header length, cone angles, belly lengths and what not and you have a exponential equation. Each time you change one thing you'd have to start all over again.

We test a lot of pipes and found the Mugen to produce the highest amount of power and that is the standard in .12s..for us.

Well engines do lean out as the fuel is used. But for a short 10 second run, it won't make a difference.

One question, on the engine tests, the horsepower ratings were totally different form what i've seen from any other. To keep things in perspective, have you done any dynoes with sport engines like say a 12cv-r? Also, have you done any big block dynos? If so, what kind of engine was it and how much did it make?

I'm kind of confused on what you're asking. If you look at the reviews for nitro vehicles we now include an "AS TESTED" dyno run on the equipment.

 

[kwong2001]

Oh yeah, forgot about that. Last issue I had was the December 04, which was prior to adding the engine dyno for nitro vehicle reviews.

btw, that's SOOOO awesome to add that in there. That's one of the reason why i like XRC the best. Supporting data is the best representation.