Monday, April 9, 2012

Exhaust from the motor to the turbo

It's taken quite a long time to get the most critical part of the exhaust system fabricated. There's just barely room for the necessary piping so precision was critical. Finally all the exhaust that connects from the exhaust ports to the turbo inlet is done. Exhaust crosses over from the right side to the left and then runs forward to the turbo in front of the engine. Here it is assembled on the floor.

It's welded out of 1/8" thick stainless steel tube with v-band connections to ease installation and flex couplings to avoid cracking from heat stresses.

I used up a lot of time and stainless steel tube making parts that weren't quite good enough. The first attempt at the manifolds warped so much during welding that I just had to scrap them and start over. I learned a lot about welding stainless though so it wasn't a complete loss. The next step is to wrap it up with exhaust wrap and then it can be bolted up.

Turbo placement

Before I can get much of the exhaust fabrication done the turbo location has to be determined.
Moving the radiator down and forward left just enough space for the turbo to sit right in front of the motor.

It's a pretty tight squeeze with only about 3/4" clearance from the power steering pump, upper control arm and top of radiator but it will be fine. This is not the crappy original GM-1 turbo. After many hours of research I settled on a Holset WH1C. This turbo was used on early Dodge Cummins pickups.

It's supported with a bracket attached to the front crossmember.