Comparing engine simulation programs

[John-F]

I’m trying to decide between Dynomation-5 (D5) and Engine Analyzer Pro (EAP). I did a general search on the web and within the forum, and am still not sure of the differences. Specific questions:

1) EAP has a Knock Index calculation. Is there something equivalent in D5? Seems very useful and surprised if D5 does not have some type of equivalent.

2) Several comments that EAP is more difficult to use mainly because it requires many input parameters. Does EAP use more parameters than D5 and is a more accurate model, or does D5 have more “standard” defaults and is easier to use if many parameters do not need changing?

3) D-5 advertises wave action simulation that is not mentioned in EAP. Is this capability inherent in EAP or is it a discriminator?

4) My impression is that the D-5 output seems more user friendly and could serve a learning tool much more easily than EAP. Is this correct?

5) With both, are there databases available that contain standard engine configurations and standard parts available, that can be further customized. For example, is it possible to specify a stock LS3 engine, and then add specific items such as a model xxx Corsa exhaust system or a specific CAM?

6) Any other differences, such as accuracy?

7) Both are advertised to require a PC with windows. Any experience running on a Mac with Parallels or Fusion to emulate the PC environment?

[Nick Campagna]

John, I have been using the EA Pro for a few years. I am a beta tester for their engine analyzer products. I have no experience with D5. I find the EA products very easy to use because of the flexibility. When modeling, I only change one thing at a time, so I can track the effect on changes. That is how to see the effects. I really like it, and they offer 30 day trials. I would be willing to help you if you went that way. I also find their cam design section to be outstanding, as it allows you to enter your own lift curve on a degree by degree basis.

[John-F]

Nick,

Thanks very much for your offer to help. Support available certainly makes a difference when choosing products.

Could you comment on my question 5) with respect to Engine Analyzer Pro?

Thanks again,

John

[kick2008a]

Nick, how accurate is the EAP program? I have it and it likes one cam in particular. It’s telling me to use a CC 11-753-14 281/300 839/800 115 cam in my 632 BBC. I’ve inputted all the cam profiles from RM, CC, Isky, Crane, Ultradyne and a couple others and every cam I replace it with in the program, it loses power. Thanks, Jim

Sorry, didn't mean to side track your question.

[SWR]

Nick,

Thanks very much for your offer to help. Support available certainly makes a difference when choosing products.

Could you comment on my question 5) with respect to Engine Analyzer Pro?

Thanks again,

John

The "parts library" that comes with the EA Pro is extensive and becomes bigger all the time. You can even ask other users for files of parts you want to try out at their forum. Keep in mind that ANY file you haven't measured yourself might not be as well measured as you'd like..

[SWR]

Nick, how accurate is the EAP program? I have it and it likes one cam in particular. It’s telling me to use a CC 11-753-14 281/300 839/800 115 cam in my 632 BBC. I’ve inputted all the cam profiles from RM, CC, Isky, Crane, Ultradyne and a couple others and every cam I replace it with in the program, it loses power. Thanks, Jim

Sorry, didn't mean to side track your question.

I use EA Pro V3.9 now - been using the Pro for over 10 years and I also Beta-test them like Nick - and although I almost never do anything else than turbocharged and NA imports and motorcycles I have seen a very small rate of error given that the total engine files for a combo are all correct. "Close enough"-specs are NO GOOD, and nothing beats actual cam files for cam comparison - i.e. full profiles made in Cam Analyzer or other programs - and the same goes for every other spec. The lack of correctness in such programs is very often down to sloppy users who measure with a yardstick when micrometers should do the job..

Also, when comparing cams you should always have proper valve weights and spring specs, and have the "Valvetrain dynamics" enabled. If not the cam who makes the best power often have dynamics that will float and / or kill the valvetrain, which makes NO power in the real combo. Ignore the Knock Index, the Valvetrain Dynamics and the actual spark curve you run, and you can have as much power as you want. On the PC, and only there..

An example, I have seen a 1359 hp turbo and N2O engine simulate to 1347-1362 hp depending on weather conditions, with all specs known to be correct. Probably see a bigger difference if you dyno the car 2 different sites..

[Kevin Gertgen]

1) EAP has a Knock Index calculation. Is there something equivalent in D5? Seems very useful and surprised if D5 does not have some type of equivalent.

[I don't know what D5 does. I've never run it. However, I'm pretty sure the D5 guys HAVE run our programs, alot.]


2) Several comments that EAP is more difficult to use mainly because it requires many input parameters. Does EAP use more parameters than D5 and is a more accurate model, or does D5 have more “standard” defaults and is easier to use if many parameters do not need changing?

[We DO use more inputs, not so much to come up with a more accurate power curve, but so you can try more types of modifications. How can you see if going from 2.500" journals to 2.375" journals produces significantly more power (from less friction) if you somehow can't input info about the bearing sizes (EA Pro's Bearing Coefficient input)? The way we can have all the inputs and still make the program workable for the average user includes:

1) Provide a large data base of parts (which we do)
2) Make an input like Bearing Coefficient something you can select from a general list (which we do), or allow you to enter detailed info to calculate it (which we do).
3) Allow the user to completely turn off some feature requiring inputs (like Valve Train Dynamics, or Carb/EFI Fuel Metering Simulation) and use std defaults.

When we started doing this back in the 80s (well before any Dynomation), we made a marketing mistake by allowing too many inputs. Me being an engineer thought users would like inputs to try lots of mods. Turns out most didn't. However, once you offer an input, you can not take it back or that 5% of users that liked the inputs get upset. So yes, we've got lots of inputs, but lots of ways around the average user having to think about them.]



3) D-5 advertises wave action simulation that is not mentioned in EAP. Is this capability inherent in EAP or is it a discriminator?

[We use a "finite difference" method to doing the wave action. They use Method of Characteristics. You've got to do some type of wave action simulation to be at all realistic.]


4) My impression is that the D-5 output seems more user friendly and could serve a learning tool much more easily than EAP. Is this correct?

[See answer to 2 above.]


5) With both, are there databases available that contain standard engine configurations and standard parts available, that can be further customized. For example, is it possible to specify a stock LS3 engine, and then add specific items such as a model xxx Corsa exhaust system or a specific CAM?

[See answer to 2 above.]


6) Any other differences, such as accuracy?

[Accuracy is very hard to gauge. We have people tell us all the time the results are within 1% of the actual dyno results. We think that's great, but know if the guy went to a different dyno the results could change 5-10%. We are much more interested in getting the trends correct.

Email me at kevin@performancetrends.com and I can send some info on feedback I've gotten when people do comparisons.]


7) Both are advertised to require a PC with windows. Any experience running on a Mac with Parallels or Fusion to emulate the PC environment?

[I only get 1-2 people a year asking about Macs. However, I've never had an email from someone complaining about EA Pro NOT running on a Mac, so I assume the emulations are working pretty well. Also, just download and try the Demo version. If the demo runs, the full program will run.]

Kevin Gertgen, Performance Trends

[Dave Koehler]

Welcome Kevin,

Long time user of Performance Trends products here. I don't think it's difficult at all to deal with. Yeah, like anything else, the first couple of days probably will make you go blind but it gets easier once you catch on. What is mind boggling is the amount of info it can kick out and the different ways of getting there. Now, that can make your head hurt.

You can always buy the entry level versions and then upgrade when you have more questions than can only be answered by the EAP.

IF you run a race car or a business you can figure this stuff out.
If you see an improvement of say 1% in the program by changing something the odds are good that it will do that or maybe better in real life. That's the "trend" thing Kevin spoke of. Is it going the right direction in other words?

Kevin and crew do an excellent job of keeping things up to date. Find a legit bug or even a misspelled word, email them and they have it fixed in a short time.

I haven't worked with Dynomation but have used their entry level grams (dyno sim?) sold by the CompCams group. At least it looks to me like the same programmers. EAP or even EA blows that away in terms of ease of use, built in data files, etc. IMO.

I hear a rumor that EAP may even be able to import Stan Weiss's head files sometime in the future. That would be nice.

I have settled on PT products and pipemax for seeing if any of my
"what ifs" make sense.

I'm Dave Koehler and I approve this message.

[kick2008a]

I have 3.2 or maybe 3.5, not sure.

Well, I ordered the cam it recommended, it's worth a try.

Jim

[John-F]

Thanks very much for all the information, and especially Kevin for joining in. Based on all the information here, in addition to my finding D5 does not have a database of parts makes EA Pro the way to go.

[camman]

1)

When we started doing this back in the 80s (well before any Dynomation), we made a marketing mistake by allowing too many inputs. Me being an engineer thought users would like inputs to try lots of mods. Turns out most didn't. However, once you offer an input, you can not take it back or that 5% of users that liked the inputs get upset. So yes, we've got lots of inputs, but lots of ways around the average user having to think about them.

Personally, I think the more user inputs the better. I just don't trust programs that make too many asumptions on behalf of the user.

[Steve Smith]

How do these work out for non-standard engines? If I wanted to model a 1948 Diamond T Lincoln Hercules engine would it work or does it rely on libraries of V-8's? When I slap three Webers on that engine will either of these simulators be able to model it?

Edit: Did some studying, as I should of first and would like to modify the question.

Will I be able to exploit the different simulator levels without a flow bench, Cam Doctor etc etc. There's quite a price difference between the midlevel and EA Pro. Would a home shop builder be able to fill in all the blanks in the Pro to get something useful?

[Nick Campagna]

Your sim will only be as accurate as the info you enter. While the program can operate with approximate values, it cannot be clairvoyant. There is a difference in flathead (L or F head), 283 Chevy, and 392 Chrysler heads and their combustion dynamics. Download the free demo of EA Pro 3.5 and get a feel for it.

[SWR]

How do these work out for non-standard engines? If I wanted to model a 1948 Diamond T Lincoln Hercules engine would it work or does it rely on libraries of V-8's? When I slap three Webers on that engine will either of these simulators be able to model it?

Edit: Did some studying, as I should of first and would like to modify the question.

Will I be able to exploit the different simulator levels without a flow bench, Cam Doctor etc etc. There's quite a price difference between the midlevel and EA Pro. Would a home shop builder be able to fill in all the blanks in the Pro to get something useful?

Steve, you do not need to have everything spot on, i.e. make a flowbench and buy a full electronic cam stand, to see the trends, what does this approx cam do in this engine and so on... But if you want to see numbers fairly exact to what you'll probably get on the dyno, the more exact numbers the better. I have modeled everything from 3.5cu.in. gas model airplane engines, 600cc sportbikes and 3.4-liter turbo and N2O drag engines to a Rolls Royce Meteor (27-liter non-supercharged RR Merlin used in a tank) in the Pro, and I think I have used the libraries that come with the Pro just 3 times in 10 years, as I model so much odd stuff there's no files for it anywhere...