While you're doing that plenum.....
 

Hey guys, as long as you have that new plenum in your hand, take a peek inside. Most of them have casting goobers and minor defects in the surface that impede flow. If you have a dremel or handheld die grinder remove the bumps. I was easily able to access all of mine with a hand-held die grinder. After you do that, spend $10. on a 3M scotch brite/emory wheel (they are about 2.5" diameter and easily fit in a 75mm plenum. Polish the S**T out of the inside! This setup yields a smooth surface and enhances flow, better flow equals HP, every little bit helps on a NA 2V 4.6. Also, if you dislike the "whistle" on part throttle, (mine sounds like a belt chirp) carefully break the edges on the IAC ports (Idle air Contoller) and EGR port* (especially here, because the incoming air has most velocity at this point) I used a ball grinding end of about 3/4" on my die grinder. When finished, wash thouroghly in a pail of warm suds (clean completely with a rag and toothbrush through all ports. I noticed alot of you are installing TB/Plenum setups, I figured I'd through out this tip to y'all.
John

RE: While you're doing that plenum.....
 

thanks john, i'll check it out when i get mine in a few weeks.

RE: While you're doing that plenum.....
 

which plenum did you buy?

RE: While you're doing that plenum.....
 

I bought the professional products satin 75mm plenum, and I'm using the pro products 70 MM throttle body. I have no complaints with either, the TB is smooth, no hang ups, and the fit and finish of the intake is great for the money. I paid $215 fo the combo. I don't know if anyone offers the inside polished, plenty offer the outside. To me, the inside is what I care about. I remember years ago that FORd "found" 8 hp in the Probe Gt's intake by extrude honing it. This process basically polishes the runners of the intake. That is the one thing I do like about the factory plastic intake, the runners are smooth, unlike cast aluminum.
John

RE: While you're doing that plenum.....
 

But, with this plastic intake, you cannont port it.. You are just stuck with how it is.

RE: While you're doing that plenum.....
 

Thats why you whack it with a hammer, contact ford about the recall on your cracked intake. Then spend the money you get on a performance metal intake :D

RE: While you're doing that plenum.....
 

So you are happy with the PP plenum+t-body? I might go with that one as a low cost alternative to the 300 dollar combo I was considering before. Where did you order yours from for $215?

RE: While you're doing that plenum.....
 

i just recived mine in the mail today $215 from ebay

RE: While you're doing that plenum.....
 

i dont know if its just me, but what is the point of spending 250+ on a plenum and whatever of a intake and only get like 5WHP... seems like a waste of money for little HP... if i am wrong please correct me.

RE: While you're doing that plenum.....
 

consider yourself corrected