CHRISPY

We have lots of discussions on all out race cams but what about cams that will pass emissions (through cats) yet yield big power gains. (with program tweaking)

Using my old combo for an example. I had a 230/230 112LSA .59X XE-R cam, 360ci motor and managed to get it to pass with tuning changes (idle, timing, temp etc) both roller and idle emissions testing

It wasn't a walk in the park however

We all know that as a motor increases in displacement you can run a larger cam without triggering as many misfires at a given rpm

So lets look at what has worked and break it into displacement ranges:

346ci

383-395 stroker

408-434 super-stroker

Thoughts?

marc_w

This thread is exactly what I'd like to hear about. It's not too common to hear technical talk about emission legal cams anymore.

I'm looking to set up my motor around stump-pulling, 6000rpm-max, torque, so I think I'm looking in the 'emisision legal' range of specs.

Is there a general rule of thumb for this? Like maybe every 10ci, go up 2* in duration?

Will the extra 18ci my 6.0 has, make any noticeable difference from a standard LS1?