Engine Design Software

[dive!dive!]

I saw a mention recently on one of our forums about engine design software and now cant remember where I saw it ! Does anyone have experience of software packages that work for our motors ? The sort of thing I'm thinking about is where you input all the engine parameters (bore, stroke, CR, head flow, cam etc etc) and can then see the effect of changing cam for example. I know the dyno is the final arbiter on this :-) I don't mind spending 'some' money but am not looking for pro packages costing big $$$
Thanks
Steve

[Doktor]

Dub Dyno for Android platform.
There is also a free version called Dub Dyno Free with limited options.

You can also try to find (or buy) Desktop Dyno, for Windows platform.

Maybe this is what you need...

[Torben Alstrup]

One of the most comprehensive systems that can be bought for normal people´s money is the Enngine analyzer sold by Performance Trends. The more precise data you punch in, the more accurate it is. I use it a lot, especially when I configure new engine combo´s and engines that I do not know too well. For instance, right now I am working improving a Triumph TR6, which actually pulls quite nice figures at peak, but has annoying flatspots and a stumble that 3 previus "British" guys coulld´nt remove. - I allready know what´s wrong. Now I just need to figure out how to make it better without loosing power. Good brain gymnastics 

T

[dive!dive!]

Torben - cool , that's the one I was looking for. Thanks!

[dive!dive!]

Hah. You mentioned a TR6... I always sort of fancied one of those, you know, classic British sports car blah blah. So I just took a look at what's available in terms of tuning one...the VERY quick look I just had says the std motor is 125bhp (and that from a 2,5 S6!) and they can be made to give 190-200 bhp, but that looked very expensive...talk on one forum of £2.5k cranks etc.
I'm sticking with my flat 4!
Steve

Oh - and I downloaded the Perf Trend demo - looks very nice , $109 to buy which is ok.

[Brian Rogers]

I did a casual look for an Apple app but didn't find anything. Desktop Dyno was used and discussed on the old forum a lot. Any users here?

[brian e]

I have used desktop dyno, and I didn't think it was too great.  Kinda clumsy and hard to do a lot of side by side comparisons. 

Right now I use Pipemax.  For the price, it gives a ton of info, and its super easy to use. 

I will probably be getting EA Plus in the future.  It also seems easy to use, and easy to compare a bunch of different combos without much hassle. 

I think the biggest problem with any simulator is the "garbage in, garbage out" problem.  If you don't have real accurate flow bench numbers from YOUR cylinder heads it is all just a guess. 

[modnrod]

I have Desktop Dyno, I bought it out of curiosity but I never use it for the reasons mentioned above.

I have had a few versions of Engine Analyser over the years, excellent product all round once you get to know it's tuning peculiarities. The book provided with it is a great source of info. Even without accurate input data, it can teach you a lot about what an engine combo will probably like, so using that info and applying it to real world parts available you can get what you've got going a lot better.

I have Pipemax also, I bought it last a few years ago and if it was a book it would be dog-eared and frayed.
 

[Torben Alstrup]

Hah. You mentioned a TR6... I always sort of fancied one of those, you know, classic British sports car blah blah. So I just took a look at what's available in terms of tuning one...the VERY quick look I just had says the std motor is 125bhp (and that from a 2,5 S6!) and they can be made to give 190-200 bhp, but that looked very expensive...talk on one forum of £2.5k cranks etc.
I'm sticking with my flat 4!
Steve

Oh - and I downloaded the Perf Trend demo - looks very nice , $109 to buy which is ok.

Sounds just about right. I have had them up to 204 hp with carbs and crank trigger ignition and street trim.

Get the Pro vewrsion. Its better.

t

[dive!dive!]

Torben
As you have used this software, could you comment on what I've found ?
I've put in my engine specs as accurately as I can - I've had my heads flowed ( 163CFM @ 25" @ 0.5" lift) so that part is accurate and I know the length and size of my exhaust. The only thing I've taken a guess on is the muffler - I used one of their examples for an aftermarket 2" exhaust with a flow of 180cfm.
Using that data, I get 132 peak hp in the software. The last dyno run I made made approx. 130 so that fits really well. (just out of curiosity I put in the specs for a typical 2.3litre '200hp' motor and the software gave pretty close to 200hp...)
Now, I've often thought my motor needs more cam....yet increasing the duration from 244@0.05 to say 260 seems to make no difference to the power the software calculates, yet in real life I guess we would expect a noticeable difference.
However, changing the muffler to one that is more free flowing seems to make a huge difference.
I know this is just simulation  but wonder if I'm using it wrong ?
Cheers
Steve

[Dougy Dee]

How would changing the cam with an already optimized set of mid-performance heads increase the HP?
What happens when you keep the existing cam and increase the CFM of the heads?

[dive!dive!]

How would changing the cam with an already optimized set of mid-performance heads increase the HP?
What happens when you keep the existing cam and increase the CFM of the heads?

Because in my example the heads already have more 'potential' power than the engine delivers (so they are not optimized in this sense) , so increasing cam duration and/or lift plus an appropriate adjustment to CR should access more of that 'potential' (at least that's my limited understanding).

Increasing head flow without changing other parameters, increases peak HP, as you'd expect, but we know that having heads too big for a given cam and engine capacity doesn't necessarily make for a nice driving engine.

I must say, its interesting to play with.... albeit a bit academic as per my earlier posts.

[Torben Alstrup]

Hello
I have seen the behaviure too. In general, if the displacement is relatively large for the valve size this is what you will see, because the ports already have good port velocity. So an increase in duration will sometimes only move the power around so to speak, eventhough the time area gets increased. In such cases you should try to increase valve lift and see if it makes a difference. It usually does, because the time area improves significantly with added lift at a given duration. Also the calculated port volume plays a large role. you will soon see how the system "pays attention" to a port that is either too large or too small.

T

[dive!dive!]

Interesting. Keeping all other parameters constant (including lift at cam)
Duration     Rockers      Peak HP     Avg HP
244            1.25           132           107
260            1.25           136           103
244            1.4             139           110
260            1.4             143           106

It seems that the extra duration hurts the area under the curve and makes the motor more 'peaky', while the lift helps everything. At least on this collection of parts. Theoretically!

Steve

[Torben Alstrup]

Something ellse is annoyng the set up. Hard to say exactly what.

Send me a pm with all the data and I will have a look at it.

T

[DWL_Puavo]

Please don't continue this, now it's close that I have to spend on software when for the same money I could get beer high quality tuning parts more horsepower some chromed chinese pulley set worth nothing. Well maybe a file for a grinder and then blindly enlarge the intake ports for less velocity and shitty driveability. So software it'll be.

[dive!dive!]

Please don't continue this, now it's close that I have to spend on software when for the same money I could get beer high quality tuning parts more horsepower some chromed chinese pulley set worth nothing. Well maybe a file for a grinder and then blindly enlarge the intake ports for less velocity and shitty driveability. So software it'll be.

I read this twice, and it made me think about the topic here (I know the above is tongue in cheek, so to speak). I think the software is just another tool in the toolbox - by itself, probably not much good, but with some knowledge its a)fun and b) educational, and is very complementary to all the other stuff we do. Of course there are the head flow 'artists' who learned what works through trial and error and hours on a flow bench, these guys still make some beautiful heads and will continue to do so, software will not replace that skill/knowledge,  but combine that skill with some new science/technology and we maybe move to a different level. For me, this is a hobby and I like to learn - converting to EFI and doing all the mapping myself last winter was a steep learning curve , but it taught me loads about what my engine likes. I see this software in a similar way - it will teach me about my engine, and maybe give me some direction on what to improve/change. Enough philosophy, just my 2c !
Steve

[BeetleBug]

EA takes the guessing away from the engine building. It is a brilliant tool but as usual shit in is shit out. You need the correct input to get the correct results. And since you now know the engine output you will get the kick from matching the theory with the real life. That can be just as fun.

Below is my 1641ccm turbo mouse engine in a NA configuration with two cams, my current and a Engle TCS20 vs the exact same specs but increased size to 1835ccm;



And this is what happens when I put a Engle FK87/112 in the mix:



This is a "ordinary" 2332 with CB Mini Wegdeports with CB online flow results # -15% and the difference between long and short manifolds:



-BB-

[BeetleBug]

Guys, it appears that this interesting thread lost its momentum. Sorry if I killed it with my reply!

-BB-

[dive!dive!]

Just digesting what you posted....
Conventional wisdom would have it that as long as the heads can flow enough then increasing cam duration will increase peak power and move it up the rpm range, accepting that to get this to work then CR has to be increased as well to give enough dynamic CR. What surprises me is that how little impact changing duration alone makes - just look at the second chart - moving to an FK87 makes little change.
Interesting stuff.
Steve