N/A exaust idea
 

ok i have had this 87 n/a for a while and fixed all the electrical issues.
its got a stright pipe from the stock manifold to the mufler.
cats been removed, runs loud, but the secondary ports have been rigged up to the ACV so they open under hard acceleration, but dont stay open after 4k rpm.
was looking on mazdatrix site and saw a header that they offer for six port with a backpressure tube for the six port on it.

i was thinking of drilling a hole in the stock exaust manifold to run a pressure line to the acctuator pressure inline, adding a small gate valve to set pressure flow.

any thoughts on this are apreciated.

yeah theres no point in having them open if they close at 4k. so you probably should buy the RB street header with presilencer,the presilencer has a bung drilled in to provide the backpressure for your actuators.

oh and your probably going to have to ditch your straight pipe setup if you go that route,unless you want to weld a straight pipe from the presilencer back that would work i guess.

i have a catback sitting out in the yard right now. havent had a welder to fab it together into the straight pipe and piece together what i need. and my buddy has been pretty busy at his shop, so that has been a no go for te past while.
so i have been doing some research and trying to figure out how to do this so i can fab what i need myself.
if i could check out some details of what exactly is going on with the back pressure tube, i could fab it up. but details have not been so forthcoming.
if anyone has a pic of said device, that would help large.
the main problem that i can see is direct heat from exaust gasses. and wheather there is any flow restriction at that point, and how to get around it?

dont have the money to dump on a new header, but i got time to fab.

thanks by the way, and nice avatar!!!!!!!!!!!!!!

https://www.rx7club.com/search.php?searchid=2642956 found under "aux port activation".If you look at Coldfire's thread It may give you a Pretty good Idea as to how to use the air pump to activate the Ports without Using the Exhaust(s4)