Desktop Dyno

[inh]

i've been playing with this program quite a bit lately and i must say im impressed. Ive been plugging in all the numbers and specs for crower cams, and once you subtract 15% for drivetrain loss (the program spits out power at the crank) i think its actually pretty damn accurate. like 136hp for a stg2 cammed y8 with ITBs.

just wanted to share. feel free to ask if you have any questions

[eg6motion]

link or pics?

[K2e2vin]

How much for 42mm ITB, crower stg-3, 12:1 CR, D15B VTEC?

[inh]

im not motivated enough to put in all the specs for that engine, but you can get the programand do it yourself. PM me if you want to know where to get a copy

[inh]

here's some screenshots of my engine setup.

this is with the 'low' horsepower/torque scales selected. it shows how nice the curves are:
http://img403.imageshack.us/img403/6681/dduy5.jpg

this is with the 'auto range' selected for the power scales. it gives you a better idea of how much power it makes at what RPM, but it makes the torque curve look as big as the horsepower one. look on the right at the scale and you'll see theyre on different scales however:
http://img403.imageshack.us/img403/5230/dd2ut1.jpg

if you really want to know how much power its making at what RPM, look at the chart!
http://img145.imageshack.us/img145/36/dd3nk8.jpg

also note that the power levels are extimated at the crank, and to get a real world number, subtract 15%. I've found that using this method, its pretty damn close to real dyno numbers.

[superdewey58]

interesting

[transzex]

the programs works good if you have a V8, not very good on our motors, I gave up using it 5+ years ago.

[rushi]

I'm using Engine Analyser Pro V3.3. It's very comprehensive engine simulation program, but also seems to have some accuracy problems with I4 engines. Because it's American program and clearly targeted for V8 engines, it seems to have some problems with I4 engines too.

Most problems are the quality- etc differencies. Racing-only things on V8 are stock for Hondas. Spinning 90mm stroke engine at 9000rpm it whines "Piston speed !!EXTREMELY!! High!" "MUST use state-of-the-art reciprocating parts" etc. Some intake/exhaust related things are also not too accurate. For cylinder head flow coefficent program advices that 0.4 is stock, 0.6 is very good race and 0.7 is nearly best possible. With my flow chart (measured) I get coeff. like minimum 0.63 and max. 0.75 lol

Anyway, it seems to be pretty accurate. For my setup (42mm ITB, Crower stage 3, 12:1 cr, my heads true flow chart, 4-1 26"/1 5/8"header, D16 etc) I get something like 205hp@8500rpm, 135ft-lb@6500rpm at crank. Maybe a little too optimistic. Got something like 120..130hp@7000rpm for my D15 setup, that should be damn close to truth. 200hp for stock B18C5.


I made my decisions for IM and header sizes/lenghts according to this program, and IRL I got very good results with them. Nice tool, but remember to use your own sense too 8)