superls1

Anybody use/recommend any software packages out there for modeling engine dynamics, combinations, etc.

I am trying to find one that is both consistent and accurate. I don't mind spending some money, but I would like to be able to 'try before I buy'. I have looked at the newer versions of Pro Racing Sim's Dyno/Engine stuff, but I was never that impressed with the older version. They don't offer a demo of their most complex package, Dynomation. Anybody ever use it?

Just seems like it could be helpful in learning more about valve events, airflow, etc.

DanO

GT Power

This is what myself and others use here at work and is as accurate as the information you give it. The new VW "Twin Charger" was developed at my work (eaton) using this software. The numbers are quite good in predicting changes you make in terms of % increase/decrease etc.. The exact hp number is never as "exact" as real world but there are far to many factors in real world for software to account for, but its as close as any software i have seen and they are only usually a few hp off anyway.

Keep in mind, this is a very powerful program and takes quite a bit of learning to run properly, but when you do, you will be rewarded with the most accurate information you can get from engine simulation. I am going to try to build an LS1 model sometime over this winter using this software to try and develop my own cam profile.

superls1

Assuming I found the place you are talking about, it would be little too expensive for my blood ($28k per year license fee). Looks/sounds cool, complicated, and robust though.

Anything less expensive that is worthwhile?

bshell

iTrader: (24)

TTT

I've been wondering about this too.

DanO

Yes, its the one im talking about. No, i wouldnt reccomend it for an individual, its for corporations that can justify it.

MUSTANGEATER

iTrader: (10)

http://www.performancetrends.com/

www.maxracesoftware.com

superls1

So, I have downloaded the demo. Does anybody have any cam files (or other files) that I could use for some sample usage/testing? I am not for sure where/how to get all the data that is being asked. For example, it has a sample 1997 LS1 engine. Is a port length of 5" correct for the head? Anybody know the valve events of some of the stock cams?

Steve - Race Eng

iTrader: (1)

I use Dynomation version 2 here. I have used it for many years with great success. One needs a lot of experience with it to get good results. By experience I mean actually building engines, dynoing them and comparing results with predicted results in Dynomation. Once you are adept at this (program inputs require some tweaking) you can design a race winning engine. I have done this time and again.

I have seen the new Windows version. Graphing is better, some other improvements but I'm sticking with the version I have.

In any event, LS intake port length is 5.5" exhaust port length 3". Both port lengths need to take into consideration the intake runner lengths, taper and header length and configuration.

I am attaching four camshafts files. I assume the demo you are using will accept C1 files. You need to change the file extension to C1 from txt. I could not upload files with the C1 extension.

The stock cam is from 1997 - 2000 LS1 engines. 199.9 deg. @ .050" intake 211.5 @ .050" exhaust duration 121.4 LSA intake lobe lift .29338" exhaust .29238"

Ed Curtis grind: 240 deg. @ .050" intake dur. 236.4 deg. @ .050" exhaust duration 111.7 LSA intake lobe lift .34449" exhaust .34547"

What I believe is a GM Hot Cam: 218.7 deg. @ .050" intake dur. 229.2 deg. @ .050" exhaust dur. 111.7 LSA intake lobe lift .30772" exhaust .30789"

Comp cams custom grind: 246.8 deg. @ .050" intake dur. 249.3 deg. @ .050" exhaust dur. 111.2 LSA intake lobe lift .35905" exhaust .36079"

I tested the stock and Ed Curtis grinds for JRP a while back. The custom Comp cam is from a road race engine I am doing over for a fellow with new 225 cc AFR heads. Cam was in the engine when I received it.

Have fun with your testing,

Steve

405HP_Z06

iTrader: (11)

I've been using Engine Analyzer Pro from Performance Trends for ~8 years and have had great success. I echo Steve's comments, it does take some real hands on engine building, dyno's, measuring, etc. to get good results. As long as the data you input is accurate, you will get very good and repeatable results.

Shoot me an email, aaron@andersonperformance.net, if you would like some cam, head, short block, etc files for EAP.

superls1

Thank you very much. I will give them a try. How hard is it to get a basic LSx motor setup in Dynomation? I primarily want to study the differences between various valve events. I spoke with the guy that wrote Dynomation. He indicated that it was really intended more for people trying to actually make/manufacture components. He led me to believe that the DynoSim package was better for simply testing combinations.

I am trying a version of the DynoSim software. However, I am having a hard time just getting an engine setup that will mimic stock outputs of say a 2001 corvette (LS1) and a 2001 camaro: Same heads, intake, different cams, and slightly different exhaust (but at least both were stock). I also tried to setup both a 2001 Z06 and 2002 Z06 engine combinations. However in all instances, my torque is never anywhere near (it is lower) than the reported GM figures, and the horsepower seems to be too high. Perhaps I am getting my cams entered incorrectly. How/where can I get the valve events for stock cams? I know the basics (e.g. 196/207 .467/.479 116), but from that can I determine all the valve events?

superls1

I have had a couple of people now give this software a good reference. I sent you an email from superls1@yahoo.com .

I would be interested in anything that you have. There seems to be a lot of information that I am not for sure about what to enter or where to get it.

Thanks.

MadBill

I have 3 or 4 less sophisticated programs (DynoSim, Desktop Dyno, Engine Expert, etc.) but have been spoiled by the capabilities of Dynomation (Ver.2.0 with some upgrades), which I have been using off and on for ~7 years. I think it has the ideal balance between generating precise and accurate specifications, is not too demanding re inputs, cost/value is reasonable and most important, it offers enormous opportunities to understand why, not just what, the engine 'wants'.
A couple of issues with my DOS version are:
1. I hate DOS.
2. It underestimates the required exhaust duration, forcing one to subtract 15 degrees or more from the EVC point of an existing cam when inputting the specs in order to get an accurate assessment, then adding it back on to the DM-optimized phasing if you're going to get a new grind. Similarly, when developing an 'ideal' exhaust cam, you have to add 15 or 20 degrees to the DM-derived EVC value.
3. It has a problem with merge/megaphone collectors. Just when I'm getting some nice gains with a meg-style collector, some weird math problem pops up a "Black Screen of Death", crashes the program and loses track of my files.

I e-mailed one of the suppliers, Audie Technology http://www.audietech.com/ , to ask if the new Windows-based edition had corrected these and few other minor faults, but got no reply. Will have to phone them I guess...

MadBill

PS: Hey Steve,
I too am about to spec out a cam, exhaust, etc. for a road race '02 Z06. Engine displacement and a few other details are as yet undecided, but I have suggested the 225 AFR head and possibly Burns exhaust (be interesting to see how their design program results compares to DM). The only other viable head contender I have found so far is the exchange-ported Kaytech Stage III, but it is 20 cc larger than the AFR, with only marginally more flow on the intake and less on the exhaust. (It also costs more with cores...)
I have not previously worked with the LSx engine and am still short some specs. Do you perhaps know the intake length and beginning area of the Z06 or any of the aftermarket manifolds?

Steve - Race Eng

iTrader: (1)

I have very good correlation between Dynomation and Jack Burn's software. In fact I compared my results with Dynomation with Jack on an engine I designed a few years back using his headers and merge collectors. Jack and I share views on camshaft timing for best power using his merge style collectors.

With some minor tweaking, Dynomation is right on regarding header primary length, steps and merge diameter. I warn you that other brands of merge collectors will not give the same results if you design using Dynomation.

I have not found any problems with Dynomation regarding exhaust duration. You may be having a problem because your flow inputs are not correct. I have a SuperFlow 1020 bench here. Intake flow must be taken with the manifold in place. Input low lift flows at .050" increments both intake and exhaust. Exhaust should have the header for best results or at least a right angle flow tube.

The biggest problem with Dynomation is lobe spread. The wider you make the spread, the higher the power numbers from Dynomation. I have learned to develop cam lobes using the same LSA for all tests. I then have the cam ground to a LSA I know will work from years of experience.

For intake input: runner length 16.5" beginning runner area 3.00 sq. in. minimum port area 2.38 sq. in.

That will get you started. The minimum port area - beginning runner area inputs are very critical - in fact more critical than the flow figures for determining camshaft profiles. They determine the taper and charge velocity through the port. I do not have the AFR minimum cross section data. I will give Tony a call. The minimum cross section above is from a set of reworked "stage one" cnc ported heads.

Dynomation should not be used to predict actual horsepower numbers. It is often quite accurate but only on engines similar to what was used in developing the program. Curtis did much of the testing using a small block 350" Chevy with four barrel carb as I recall. So it works very well (gives very accurate power numbers) on a carbed engine around that displacement.

Dynomation very accurately shows trends when you overlay torque and power graphs. If it shows an improvement in power in the rpm range of importance when you make a camshaft or other change, you will always see an improvement on the dyno and at the track.

I will flow the AFR 225 cc heads I have here with LS6 manifold, Fast manifold and radius plate in the next few weeks and post the results. Very busy at the moment with other work.


Steve

ddnspider

iTrader: (26)

would anyone happen to have LS1 specific setups for Dyno 2000/2003 Advanced Engine Simulations?

MadBill

Thanks for the fast and detailed response, Steve!

All roads seem to lead to Burns re exhaust; fortunately this customer wants the best, regardless of cost!

The EVC concern was detailed to me by Allan Lockheed, who did the Engine Expert program and provided Curtis with a lot of input in developing the Dynomation program. I had mentioned to him that in my sims, DM often seemed to want suspiciously early (22-30) EVCs.

I too noticed the results get pretty flakey in the absence of good low lift flow data.

I had noticed DM's preference for wide LCAs, but on a couple of recent engine builds (both Alfa Romeo twin cams, with vernier adjustable cam timing), careful on-road testing confirmed the DM recommendations. (Dyno day coming up soon.) I concur though that one has to leaven the DM results with real world experience.

The runner specs will be a big help! I too noticed that the minimum area is a huge deal. You can give up a lot of flow in exchange for small, efficient ports. (of course with DM, you can pretend that the flow stays the same while you shrink the minimum area...) BTW, I dropped Tony an IM from another thread here re the port areas.

Look forward to your flow data, Steve and thanks again for the invaluable insight!


Best regards,
-Bill Ball