Hi All,

I've had a search on both the forum and through google and can't find an accurate template for making a cylinder head flange plate (make my own exhaust manifold). I've measure the spacing, but it's difficult to get it accurate. I've now got the dimensions close to work well, but would still like an OEM template to confirm what I have. I've even gone to the effort of 3D printing portions (limitations of the 3D print are 220mm x 250mm) of the plate to confirm that my dimensions work with my series 3 head. I'd say I'm within 0.1 mm on all dimensions at the moment.

Once I have a flange plate water jet cut I will post up dimensions for all to make use of.

Woz

 

Have you laid out a new exhaust gasket on your drawing to double check alignment with stud holes and centering of exhaust port? I did a intake manifold shim using a new gasket to check final layout. My intake shim was tapered so had to have it done on 3 axis CNC machine. I tried to find Blue Print for engine intake layout, with out any luck. Rgds David

 

 

I had some water jet plates made for manifold covers, but the tolerances were not tight like the CNC mill; I had to drill out all holes on drill press. If you have have one manifold off the engine, you may want to try drill bits to find largest "?/64" one you can insert. Use that for your CAD drawing you send to the machine shop. See if they can accept a +.005 to -.000 tolerance for these holes. All literature I read on exhaust manifold headers, indicate the square holes in the plate should be slightly larger that cylinder head openings; maybe a +.03 to -.000 tolerance. In the end, I just went with off-the-shelf headers on sale. Rgds David