This should be an easy job compared to the other jobs I have done (vacuum hose project) etc. However, I ran into a little problem with the stud bolts on the manifold. Apparently one of the four bolts has a tapered end and is smaller in diameter than the rest of the stud bolts. I had no problem taking any of the bolts off, but have found out for some reason or other none of the bolts will thread into this hole, the rest of them are fine. All of the bolts are 10mm 1.5 pitch. I tried rethreading the stud bolt, but with no success. The hole for this one bolt is obviously smaller because a smaller bolt such as an 8mm will fit but not thread. All of the holes should be the same, nothing broke off on the removal. Any feedback would be much appreciated. I am trying to avoid taking it into the shop because mechanics seem to screw up these cars even more.

 

Downpipe installations on a FD are far from easy.

All studs have the same size and thread pitch and are not tapered. There are two stud lengths, which might be the source of your confusion.

 

That tapped hole is damaged. You should get an M10x1.5mm plug tap and chase those threads clean. In fact, take an extra moment and chase all 4 tapped holes clear (it shouldn't take much force), and you should be fine.

Dave

 

Thanks for the info, i'll give it a try.

 

are u spining the bolt right or left? lol jk, hope u get the problem solved

 

hahaha, nice one AF1...

yeah all four bolts should definitely be the same type thread, so try the plug tap & chase & good luck...
& downpiping can be tricky so good luck with that too...

 

sounds like you might have crossthreded it, you might want to tap & chase it.