I will start with this build saying that it is fairly easy if you have a; ban saw, grinder(hand held or table dosent matter), ziz wheel(cutoff wheel), TIG welder and someone who can use it
You will need your de manifold(the entire thing), your aftermarket manifold of choice... i found that the greddy style sr20det mani worked the best/looked better to!
the things you have to consider are...AAC, IACV, Vac Lines,runner length, coolant port on intake. overall intake hight. throttle body.throttle cable mounts.
i started by measuring the distance between each runner. go up the runner about 3'' where each runner is about 1.5'' apart
this is where you need to make the cut.
make sure when you cut the stock upper manifold, the flange that bolts to the head is 90* straight up and down.
then you need to take your aftermarket intake anddo the same thing by cutting the runners off... get close to the plenum but leave room for error! "It's easy to take metal off...almost imposible to add it back and get it right!!!"
as you can see my ban saw sucks and cuts uneven so here is where the ziz wheel and grinder comes into play to even the runners up so it can be welded.the biggest part of this is to make sure that the flange that bolts to the head is 90* straight up and down this way the two sets of runners will match up so you can weld them together
ok so now that you have your two peices cut... mate them together and see what you need to adjust for it to work... like the coolant nozzle that is on the frontal most part of the OEM mani. since i wanted to keep the greddy style runner length the plenum was almost touching the nozzle that the radiator pipe goes onto... so adjust it and tack it once saticfied.. once tacked, look for any problems? i didnt have any. so i continued to weld the runners together
i havent finnished the next part so ill put pics on asap!!!
ok now that the plenum is on we need to worry about the aac, and iacv, take the stock plenum and ban saw the stock aac/ iacv mounts off...take the AAC mount and place it where the sr AAC is suposed to go and weld it up...there will need to be some gaps filled in... but its ok... then find a drill bit that is about the size of the IACV mount hole and drill into the plenum(according to your AAC placement) and weld the IACV mount over the hole. if you want to do a remote IACV you can do that Too but i desided not to...then bolt up your AAC and IACV this is the trickyest part about the entire process and i WILL post pics asap!!!
all that is left is to bolt on your throttle body (de only) the stock DE throttle cable mount will fit on the greddy mani so no need to make a custom one. hook all you othe vac lines up and screw in vac. hard ware that comes with the manifold.
