Author: PlasticPower8500 from Sixthsphere
Original Post: Located here
Well, since we had a thread that we need more articles, here's a quick one.
I just got done adapting a DSM cast iron manifold to my 5-bolt 2nd gen DOHC head.
A few common things about DSM manifolds:
- If you have a 3rd gen, all you need to do is possibly drill out one or two holes. That's it. There should be no guide for that because it's basically a bolt-on.
- If you have a 1st or 2nd gen, follow this guide.
- DSM manifolds only fit DOHC S-Series engines, I don't know about SOHC, and you shouldn't even be having those thoughts.
|Here we go. This is how the FelPro gasket lines up to the manifold. In reality, the ports on the head are smaller and line up pretty damn good:
FelPro Saturn exhaust gasket.
|Save these tabs. Certain manifolds you don't have to, because they have extra material to drill the top holes in. This one didn't. You'll use the tabs to make the top bolt holes:
|Reverse the tabs and weld them up to the two spots where you will have bolts. You will not need to drill the tabs, they line up perfectly:
|Here it is with the tab welded from the back. You'll want to make sure your welds are good. Also, make sure you don't try to make the tabs "flush" with the surface. They don't need to seal, they just need to keep the manifold attached. If you make them "flush" you're running into a possibility of them sticking out a bit, and it will not make a good seal. Of course, it all depends on your skill level.
For my purpose, because my head is actually port matched to the bigger FelPro gasket, I decided to port out the manifold some. I didn't care about smoothness, so that was the result.
|That's it! Bolt it up and enjoy:
There are many varieties, and if you get the shiny eBay kind, make sure you weld metal support tabs under where the pipes connect to flanges, specifically where the wastegate flange goes into the collector. Most manifolds already come with those tabs, but some might not have ALL the necessary tabs in place. Otherwise, these things are pretty sturdy, just don't spill coolant on them when they're hot!