everyone I can find isn't free, are there any free ones?? or ones with free trials?

 

http://www.proracingsim.com/

I think its on sale this month.

 

If you want a thumbnail sketch comparison of the four products, I did an article on them for Comp Cams Power and Performance Magazine back in 2004 http://www.powerandperformancenews.c...formance04.pdf (see p. 22). They're all good products.

The relative results from the simulations of one cam versus another are very helpful in making a final selection. I designed my own current cam using DynoSim and I'm very happy with it. I can't tell you how good a learning tool DynoSim has been for me personally and I've been wrenchin' for over forty years.

Steve