I'm putting together a TPI to use with a turbo. I'm using a set of Profiler heads. I mention the Profiler heads as they do not use an exhaust crossover. My question is about the small holes in each lower intake runner that appear to be for the EGR system and/or cold start system. Do I need to plug those holes to keep from putting boost into the valley due to the intake's exhaust crossover is partially exposed to the valley due to head design? If yes, can the plugs on the bottom of the intake (with 14mm allen socket) be removed easily to access? Does installing an EGR delete plate eliminate access to these holes?

Thanks in advance - Jim

 

Those holes do not lead into the valley. If you remove the heat shield from the bottom of the lower intake manifold that faces the oil valley, you will see that it is all plugged up underneath. The holes in the runners only lead to the EGR crossover to recirculate exhaust gases from, boost pressure will only force it back towards the cylinder head, not the oil valley...

 

Thanks. So if I'm running an EGR valve block off, then I should no issue. Sounds great.

 

No issue at all. Remember to disable the EGR in the tune...

 

No EGR to disable - running a Megasquirt. Thanks again for the help.