Is there anyway you can tell if an fd has been street ported?

For example do they idle differently compared to stock?

Thanks
Paul

 

There was a thread about this a while back. The only real way to tell is to check the ports. However, porting does affect the idle making the idle "lumpy". How lumpy the idle depends on the size of the porting. A mild/slight port might not affect the idle at all. Also, porting affects the idle vacuum reading. Normal non-ported engines read 17-20inHg for idle vacuum around 800rpms. Idle vacuum also depends on other things like rpm, altitude, etc, so that's not necessarily a good way to tell.