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Join Date: Apr 2005
Location: Wilmington,NC
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Build specs for SC heads in Turbo application

Since their seem to be a lot of fun, but non-turbo related threads, springiing up up recently (due to cabin fever, no doubt), i thought i would re-focus by asking you guys that are experts about the build specs on some heads i will be using for an upcoming turbo project. A recent post by Don regarding the short life of the valve guides on his new top end got me thinking about posting this as well. Also, i just finished reading in Frere's book about the problems the factory encountered with valves and guides in developing the 917/10

Build specs:
-Slightly flowed stock 80 SC heads (Not great, i know, but it's what i have, as the motor will be built using as many of the parts i have in my inventory) twin plugged, ported for use with Carrera manifold
-Standard SC bottom end with usual rebuild goodies
-Low compression 95mm JE pistons and re-using my nickie cylinders (again, for cost reasons).
-Carrera manifold
-Either TEC-Gt or Megasquirt EMS... i am familiar with the MS for N/A, but am still on the learning curve of the TEC, have just installed in the 930
-Twin garret turbos, size appropriate
-Factory WG with .8 spring, boost adjustable

Anyhow, my question is this, what particular areas of concerns are there regarding valve guides as well as valves in building these heads? Are standard sodium filled valves ok for the exhaust, or are inconel valves, like don used necessary? Maganese bronze guides needes?

I guess my main question, is what needs to be done to these heads to make them stand up to use in a turbo motor? BTW, this motor will be going into the 914/6 once the 2.7 expires or i get tired of it... either of which could happen pretty quickly as it will be mostly a DE/track/ hillclimb car. Thanks

'79 930/934 replica
80 RSR-look(Now in Sicily)
914/6 2.7 (Projekt 908/3)
1965 Karman Ghia-Class winner 2007 Carrera Panamericana/Ducati 900ss/GhezziBrian STW
D-Zug Produkte/
Old 01-24-2009, 12:03 PM
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