Engine simulation programs ??

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Turbo231
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Re: Engine simulation programs ??

Post by Turbo231 » Fri Jun 22, 2018 8:54 am

Vannik and Dynomation seem to be coming in 1 and 2 here. And I believe they are comparably priced. What about the lower cost (<$200) programs. Does anyone use these or are they a waste of money? Thanks.

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Re: Engine simulation programs ??

Post by hoffman900 » Fri Jun 22, 2018 9:12 am

mk e wrote:
Fri Jun 22, 2018 8:48 am
MadBill wrote:
Thu Jun 21, 2018 9:52 pm
A theme seems to be developing... :-k :)
Its funny because the couple people I know with both engmod and DM say they do most of their work on DM because it's much quicker to setup and has automated iterations. Then once they have everything DM can deliver they may plug it into engmod if there are additional questions DM doesn'tanswer....but that's second hand so....
The thing with EngMod is you have to build everything. You’re not going to hit a drop down menu and select “single plane intake” or whatever. You have to measure everything, plenum volume and shape, runner lengths, runner cross sections, etc.

This may be a big deterrent for the casual user, but if you’re willing to take the time to learn, measure, and build the model, then it’s worth it.
-Bob

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Re: Engine simulation programs ??

Post by randy331 » Fri Jun 22, 2018 9:36 am

Land and sea
Stuska
super flow

Randy

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Re: Engine simulation programs ??

Post by hoffman900 » Fri Jun 22, 2018 9:40 am

randy331 wrote:
Fri Jun 22, 2018 9:36 am
Land and sea
Stuska
super flow

Randy
:roll:

I’m surprised it took the knuckledraggers this long to show up, but now that this has left the Advanced Section, I predict talks will quickly go down hill. “I’m a real man and I don’t need no stinkin computer to build my ChevyFordinator 383 bracket engine. Pressure waves? That sounds like fakenews elitist liberal science talk. I just hit the peda and it goes “rawwwrrr””.

... Or something like that. Write a sass response and you’ll get one in return.
Last edited by hoffman900 on Fri Jun 22, 2018 9:58 am, edited 2 times in total.
-Bob

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Re: Engine simulation programs ??

Post by Turbo231 » Fri Jun 22, 2018 9:58 am

hoffman900 wrote:
Fri Jun 22, 2018 9:40 am
randy331 wrote:
Fri Jun 22, 2018 9:36 am
Land and sea
Stuska
super flow

Randy
:roll:

I’m surprised it took the knuckledraggers this long to show up, but now that this has left the Advanced Section, I predict talks will quickly go down hill. “I’m a real man and I don’t need no stinkin computer to build my ChevyFordinator 383 bracket engine. Pressure waves? That sounds like fakenews elitist liberal science talk. I just hit the peda and it goes “rawwwrrr””.

... Or something like that. Write a sass response and you’ll get one in return.
LOL. This site is definitely entertaining.

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Re: Engine simulation programs ??

Post by randy331 » Fri Jun 22, 2018 10:14 am

hoffman900 wrote:
Fri Jun 22, 2018 9:40 am
randy331 wrote:
Fri Jun 22, 2018 9:36 am
Land and sea
Stuska
super flow

Randy
:roll:

I’m surprised it took the knuckledraggers this long to show up, but now that this has left the Advanced Section, I predict talks will quickly go down hill. “I’m a real man and I don’t need no stinkin computer to build my ChevyFordinator 383 bracket engine. Pressure waves? That sounds like fakenews elitist liberal science talk. I just hit the peda and it goes “rawwwrrr””.

... Or something like that. Write a sass response and you’ll get one in return.
I have some sim programs, and access to others, and when the sim results don't match the actual dyno results, I believe the dyno.
And yes I've seen them not match real results.
Maybe that makes me a knuckledragger. :lol:


Let me ask you a question, I'd like a little more power in my pulling truck engine, would you run it on a sim and make the changes it shows to be better, and just go truck pulling again assuming it's making more power, or would you pull the engine and take it to an actual dyno and try some things on it ? Keep in mind in truck pulling there's no way to validate 10-20 HP difference by the way the truck pulls. Too many variables.

Knuckledraggers pulling truck team ! :D

Randy

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Re: Engine simulation programs ??

Post by mk e » Fri Jun 22, 2018 10:49 am

hoffman900 wrote:
Fri Jun 22, 2018 9:12 am

The thing with EngMod is you have to build everything. You’re not going to hit a drop down menu and select “single plane intake” or whatever. You have to measure everything, plenum volume and shape, runner lengths, runner cross sections, etc.

This may be a big deterrent for the casual user, but if you’re willing to take the time to learn, measure, and build the model, then it’s worth it.
DM works 2 ways. You can do a quick and dirty using just the drop down menus but that is not a 1d sim, it's a pumping model an assumes each component is optimized.....that kind of tells you what is possible for the combination your looking at. It also ends to predict the lower rmp portion of the curve better where the tuning waves are weak to nonexistant.

Once that's set up you plug in the real measurements of the intake runners, headers, fuel cooling and such and run the 1d sim. You're still forced into basic configurations from the drop down menus and I know different corrections are applied depending on what you selected even if the same dimensions are used but it seems to do a pretty good good....within about 2% of dyno numbers on the dozen or so engines I have both outputs for.

You also get the compcams library, that's not a ton of help on the stuff I play with but if you're looking for off the shelf parts its helpful.
Mark
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Re: Engine simulation programs ??

Post by slo-svt » Fri Jun 22, 2018 11:50 am

hoffman900 wrote:
Fri Jun 22, 2018 9:40 am
randy331 wrote:
Fri Jun 22, 2018 9:36 am
Land and sea
Stuska
super flow

Randy
:roll:

I’m surprised it took the knuckledraggers this long to show up, but now that this has left the Advanced Section, I predict talks will quickly go down hill. “I’m a real man and I don’t need no stinkin computer to build my ChevyFordinator 383 bracket engine. Pressure waves? That sounds like fakenews elitist liberal science talk. I just hit the peda and it goes “rawwwrrr””.

... Or something like that. Write a sass response and you’ll get one in return.

I agree. Randy does have abnormally long arms.
Forgiveness is between you/your engine and God. It's my job to arrange the meeting.

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Re: Engine simulation programs ??

Post by n2xlr8n » Fri Jun 22, 2018 11:54 am

randy331 wrote:
Fri Jun 22, 2018 10:14 am

Let me ask you a question, I'd like a little more power in my pulling truck engine, would you run it on a sim and make the changes it shows to be better, and just go truck pulling again assuming it's making more power, or would you pull the engine and take it to an actual dyno and try some things on it ? Keep in mind in truck pulling there's no way to validate 10-20 HP difference by the way the truck pulls. Too many variables.

Knuckledraggers pulling truck team ! :D

Randy
You didn't ask me, but I have a question:

Do you now or have you considered using some of the modern data logging capabilities on your son's truck, or would it be cost prohibitive?

I'd use what my sim suggested (above my own personal experience) at the track as long as I could compare the data logs and weed out the variables.
He who is in me is greater than he who is in the world.

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Re: Engine simulation programs ??

Post by David Redszus » Fri Jun 22, 2018 12:35 pm

Over the last twenty five years I have used a number of engine simulation programs ranging from very expensive ($20,000 annual license) to quite inexpensive. They will not produce identical outputs; don't expect them to do so.

Most 1D simulations concentrate on hardware and the gas exchange process. They are weak on combustion issues, fuel issues and heat loss issues.

Any computer model requires validation. That becomes difficult when designing a new engine since no hardware prototype yet exists. It is much easier to make small improvements to an existing engine than to make major changes or start with a clean sheet.

What makes anyone think that dyno measurements are any more accurate than simulations?

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Re: Engine simulation programs ??

Post by randy331 » Fri Jun 22, 2018 12:51 pm

n2xlr8n wrote:
Fri Jun 22, 2018 11:54 am
randy331 wrote:
Fri Jun 22, 2018 10:14 am

Let me ask you a question, I'd like a little more power in my pulling truck engine, would you run it on a sim and make the changes it shows to be better, and just go truck pulling again assuming it's making more power, or would you pull the engine and take it to an actual dyno and try some things on it ? Keep in mind in truck pulling there's no way to validate 10-20 HP difference by the way the truck pulls. Too many variables.

Knuckledraggers pulling truck team ! :D

Randy
You didn't ask me, but I have a question:

Do you now or have you considered using some of the modern data logging capabilities on your son's truck, or would it be cost prohibitive?

I'd use what my sim suggested (above my own personal experience) at the track as long as I could compare the data logs and weed out the variables.
We don't currently have data logging on the truck, but may in the furture. Some of the other trucks have it. But, I don't know what you could log that would tell you if you made more power after a change to the engine. The variables at the track are too many. It's different track and different sleds with different set ups in the sleds every event. The sled speeds and distances pulled change too much to know if there was a small change in power. All the front running engines have been on the dyno and most of them several times. It's not like a drag strip where you can judge a lot by et slip.

As for me, I'll stick to what I've seen on the dyno till I get the chance to dyno again, even if a sim disagrees with it.
Maybe if I had a high end 3d sim, but I don't.

Randy

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Re: Engine simulation programs ??

Post by Dave Koehler » Fri Jun 22, 2018 1:07 pm

Randy,
Since pullers, mudders and such never get a chance to make test laps I have often thought one of those rear end mounted torque sensors might be a worthy investment. Real time Dyno Truck.
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http://www.koehlerinjection.com
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Re: Engine simulation programs ??

Post by Frankshaft » Fri Jun 22, 2018 1:19 pm

David Redszus wrote:
Fri Jun 22, 2018 12:35 pm
Over the last twenty five years I have used a number of engine simulation programs ranging from very expensive ($20,000 annual license) to quite inexpensive. They will not produce identical outputs; don't expect them to do so.

Most 1D simulations concentrate on hardware and the gas exchange process. They are weak on combustion issues, fuel issues and heat loss issues.

Any computer model requires validation. That becomes difficult when designing a new engine since no hardware prototype yet exists. It is much easier to make small improvements to an existing engine than to make major changes or start with a clean sheet.

What makes anyone think that dyno measurements are any more accurate than simulations?
Maybe because it's actually tested, and not SIMULATED?

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Re: Engine simulation programs ??

Post by David Redszus » Fri Jun 22, 2018 2:27 pm

Frankshaft wrote:
Fri Jun 22, 2018 1:19 pm
David Redszus wrote:
Fri Jun 22, 2018 12:35 pm
Over the last twenty five years I have used a number of engine simulation programs ranging from very expensive ($20,000 annual license) to quite inexpensive. They will not produce identical outputs; don't expect them to do so.

Most 1D simulations concentrate on hardware and the gas exchange process. They are weak on combustion issues, fuel issues and heat loss issues.

Any computer model requires validation. That becomes difficult when designing a new engine since no hardware prototype yet exists. It is much easier to make small improvements to an existing engine than to make major changes or start with a clean sheet.

What makes anyone think that dyno measurements are any more accurate than simulations?
Maybe because it's actually tested, and not SIMULATED?
Yes, but not accurately. Read SAE J1349 and you'll see why.

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Re: Engine simulation programs ??

Post by hoffman900 » Fri Jun 22, 2018 2:31 pm

David Redszus wrote:
Fri Jun 22, 2018 2:27 pm
Frankshaft wrote:
Fri Jun 22, 2018 1:19 pm
David Redszus wrote:
Fri Jun 22, 2018 12:35 pm
Over the last twenty five years I have used a number of engine simulation programs ranging from very expensive ($20,000 annual license) to quite inexpensive. They will not produce identical outputs; don't expect them to do so.

Most 1D simulations concentrate on hardware and the gas exchange process. They are weak on combustion issues, fuel issues and heat loss issues.

Any computer model requires validation. That becomes difficult when designing a new engine since no hardware prototype yet exists. It is much easier to make small improvements to an existing engine than to make major changes or start with a clean sheet.

What makes anyone think that dyno measurements are any more accurate than simulations?
Maybe because it's actually tested, and not SIMULATED?
Yes, but not accurately. Read SAE J1349 and you'll see why.
And don’t forget everyone’s dyno and flowbench reads low. If they are “reality”, then how could they vary? It’s like saying my tape measure measures short.

How is calibrating a sim program any different than calibrating a dyno, a flowbench, or any other instrument?

What is real? Am I real?

:wink:
Last edited by hoffman900 on Fri Jun 22, 2018 2:39 pm, edited 5 times in total.
-Bob

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