Originally Posted by woody
I think that is about the only place you have room to fit an SC on the xfire, unless you junk the inlet plenum and fit it between the V like the SRT. Something that has just occurred to me is whether there are any issues with running higher that atmospheric pressure on the plenum; the internal inlet tract switchover flaps/valves may not be designed to function with reversed pressure differential. I'm sure it will be OK but you never know. There's also the myriad of other actuators that are vacuum driven to consider. From the calcs I did a while ago for the Rotrex I don't think anything more than 3-5 PSI is practical anyway with 10:1 CR, so it may not be a problem. I'm hopefully tearing the plenum and heads down this weekend so I'll let you know what I find.
I think the variable intake plenum might create just a tad of lag in response time due to the volume change when switching between ports. I would like to weld up a S/C intake manifold at a later time, when everything else is mounted and proven.
Do you know how they managed to lower the CR to 9:1 on the SRT6? Are they using stock 3.2L pistons and connecting rods, or are the heads machined different?
I look forward to hearing about the teardown!