Datsun Roadster Forum-311s.org

From what I have read on this site, there are two ways of mounting the turbo. The only way I have seen is to mount the turbo tucked under the manifold. I hear others have mounted the turbo on top. Does anyone have a picture of such a setup? I am weighing my options. I figure the turbo on top would be easier, and give me a greater variety of trubos that will fit, but also cause a good deal of heat right next to the brake MC. Considering venting of some sort, heat sheilds. Would love to see / hear about what other people have done.

My T25 is top mounted.

http://www.311s.org/phpBB2/album_pic.php?pic_id=48

Heat is definitely an issue! I had the exhaust manifold, turbo, and downpipe ceramic coated. The downpipe (stainless steel) is then wrapped in header wrap. I have a ceramic coated, stainless steel, heat shield for the master cylinders. I also have that stick on reflective heat barrier on the master cylinder heat shield and on the underside of the hood. Even with all that, it still gets toasty warm! Not too bad though. I have not had any problems with boiling brake fluid, baking off paint, etc. After a couple hundred miles of freeway driving on the way to Shasta in the heat of the day, the master cylinders were cool to the touch. Sitting in traffic seems to be where the heat builds up.

The top mounted turbo is the way to go from a serviceability standpoint. I have had a number of times where I needed to pull the turbo lines off, re-do intake pipes, or tighten loose mounting bolts. What a nightmare that would have been if the turbo was down low. Plus, I just think it looks cool!

Bottom line is, top mount vs. bottom mount each have their relative merits. I chose top mount. Travis Rowe (TR) on this site chose bottom mount. I'm sure he can chime in with his impression of the route he took.

Hope that helps!

Dave

Above or below-- that is the question...

On the SR20DET conversion that we are currently working on, I opted to mount the turbo below the manifold like Nissan intended.



This certainly was not the easiest way to do this project as the turbo must be placed very, very carefully so it does not foul the steering shaft, frame, or body, or engine block.

I like it mounted below as it keeps the CG lower, keeps the heat away from the master cylinder and lines, and it looks 'stock'.

Yes, a top mount turbo is much easier to mount, looks sexier to some, but placing a little glowing oven next to the brake master cylinder and hood in the already-too-small roadster engine compartment did not look like a good idea to me.

Dave has gone to great lengths to make sure that he protected the brake master and hood with his top-mount, and he has done a hell of a good job on his car...

If you do decide to put anything larger than a T25 turbo on your car, then you will likely have to go with a top mount turbo, there is just not enough room to mount it down below.

Michael
Spriso Motorsports