What size bolts do I need for the plenum extension cover/distributor cover? I bought a cover without the hardware, just in case your wondering why I can't match up the stock bolts. I know they are small metric bolts. I tried a few different sizes and did a couple different searches with no luck. TIA, Nick.

Nobody knows the answer to my question? Maybe I have to go to GM??

Well I bought a tap to chase the threads on mine. Went to look for the tap and the only one I could find around that size was 4mm x 070. The reason I did not post before was that I was not a 100% sure. Seeing as no one else is speaking up I went and posted anyways.

By the way you can by the screws at www.tpiparts.net The plastic cover uses a screw with a bigger head that has a washer shape. The metal one that came on the Corvette uses a standard head. Hope this has been of some help to you.

if it helps,there the exact same size as the screws used to hold the TB plate to the throttle body.

this is what i used on my 88 iroc when i bought the alum vette cover,GM dealership couldnt figure out what size they were.

The screws for the corvette cover, you gan buy from GM for like 7 bucks a shot.... waste of money. I still havnt gotten around to finding screws for mine

as i said earlier...the screws that hold the tpi plate on the throttle body,are a perfect match for the vette extension.

Thanks for the tips guys. I will be taking one of my TPI plate screws and find some screws hopefully. -Nick.