just broke exhaust stud ..HEELLPP!!!
01-29-2004, 07:55 PM
#17
Rennlist Member
Originally posted by Danno
" is there supposed to be a bolt that goes through the hole in the flange (to the right of the 3 studs) on the downpipe that goes to the block?"
Yes, there's a bolt.
"That is how Porsche designed it. I've gone 30k miles without the bolt though. With an aftermarket turbo, the bolt can be very difficult to install (i.e., "not gunna happ'n")."
What does the turbo on the other end of the downpipe have to do with the bolt fitting? I guess if the hot-housing placed the flange of the downpipe in a different location, the bottom of it would end up in a different location. I find it's best to just barely intall the turbo-mont bolts, then install the downpipe bolt to the block, then go back and tighten up the turbo-mount bolts. I guess there's some wiggle room that way.
Without that bolt clamping the downpipe to the block, you've got the entire weight of the exhasut system hanging off your turbo! Probably not as big a deal as the torque that's generated by a lever arm that's 8-ft long. Your muffler bouncing up and down an inch or so can generate quite a bit of torque by the time it arrives at the turbo. Anyway, I've seen a number of turbos with broken center sections from this flexing of the exhaust. I go to pull the turbo/downpipe off and wow, the bottom of the turbo is still sitting on the engine-mount!
" is there supposed to be a bolt that goes through the hole in the flange (to the right of the 3 studs) on the downpipe that goes to the block?"
Yes, there's a bolt.
"That is how Porsche designed it. I've gone 30k miles without the bolt though. With an aftermarket turbo, the bolt can be very difficult to install (i.e., "not gunna happ'n")."
What does the turbo on the other end of the downpipe have to do with the bolt fitting? I guess if the hot-housing placed the flange of the downpipe in a different location, the bottom of it would end up in a different location. I find it's best to just barely intall the turbo-mont bolts, then install the downpipe bolt to the block, then go back and tighten up the turbo-mount bolts. I guess there's some wiggle room that way.
Without that bolt clamping the downpipe to the block, you've got the entire weight of the exhasut system hanging off your turbo! Probably not as big a deal as the torque that's generated by a lever arm that's 8-ft long. Your muffler bouncing up and down an inch or so can generate quite a bit of torque by the time it arrives at the turbo. Anyway, I've seen a number of turbos with broken center sections from this flexing of the exhaust. I go to pull the turbo/downpipe off and wow, the bottom of the turbo is still sitting on the engine-mount!