headers hit motor mounts on BBC?

[GRAYTEXK5]

ok, I'm finally trying to stuff the 454 into the K5...but when I went to bolt the motor mounts onto the block...it hits the front header tube on the driver side, so I can't get it on all the way. it seems like it's not hitting by much. it's right on the corner of the mount. would it be ok to grind a little off the mount to make it clear, or will this weaken it, and make it unsafe? also, there's like a plate that bolts between the block and the actual mount on each side. when I removed that, the mount cleared the header, just barely...but the bolts didn't quite tighten down all the way. anyone know what these plates are for, if they are necessary? could I just remove them, and maybe use shorter bolts or something? anyone else have this problem, or know of a way to fix it? any advice would be greatly appreciated. thanks.

 

[HarryH3]

I would notch the corner a bit. As long as you don't intrude on the bolt head area the strength won't be affected much.

Those triangular plates behind the mounts are where your transmission support rods bolt up. I would leave those there and use the supports.

 

[GRAYTEXK5]

umm...what transmission support rods? I have never seen these. apparently they've never been on this truck as long as I've had it.

 

[jays68yak]

what hedders are you running?

 

[thor]

Sounds like you have the same headers I do. I had to take about 1/4" off the top rearmost outside corner of the mount. It won't weaken it at all. The rods that bolt to that plate should go to the cover under your torque converter.

 

[GRAYTEXK5]

thanks for the replies. I guess I'll just grind a little off to clear then. so these support rods....were they only on models with the heavy duty tranny/torque converter cover? if that's the case, that would explain why they weren't on mine when I got it. however, it does have the heavy duty one now, and I would like to put them on there, if they actually help. anyone know where you can get these? or are they not even worth the trouble? thanks.

 

[1-ton]

You should be able get a set of those support rods from a GM dealership still. You have to have a fly wheel cover with the support mounts though. Just ask for a set of support rods for a 1987 K30 with a 454 and Turbo 400 trans. There is also a support bar that goes from the transfer case to the transmission bell housing too.

 

[HarryH3]

umm...what transmission support rods? I have never seen these. apparently they've never been on this truck as long as I've had it.

Your trans should have a cast aluminum flywheel cover. On the bottom of it you'll see 2 threaded 3/8's bolt holes. One end of each rod attaches there, while the other end bolts to the hole at the back end of the triangle of steel that's sandwiched between your motor mount and your block. They add structural support for the trans.