I was washing the engine on my L earlier today, and noticed the uper intake plenum leading into the blower looks quite restricitve. Has anyone tried porting or extrude-honing one of these? Also, those new thermal barrier coatings may be useful in preventing heat soak into the intake charge. Is there any power to be found here? It seems like a bottleneck.

By the way, I did a search and couldn't find anything. If there is another thread, please give me a link, 'cause I really can't find one. Be nice, I'm only asking a question