I think the reasons why Stillen is running such a low level of boost for a couple of reasons. The number reason has to Heat. The twin-screw compressor tends to produce a lot more heat in the higher boost levels. So buy running a lower boost level the less tuning they will have to do. The bad thing about these twin-screws is that it becomes very costly and difficult to adapt an intercooler to them and on top of that, the compressors cannot produce that much psi compared to a centrifugal style compressor. The other factors I see are keeping the cost of the kit in a fairly low range. The higher the boost levels the more tuning and fuel components you will need to get. By setting the boost levels low you really don’t need to add as much fuel and ignition components to prevent detonation. Lastly since this is a positive placement compressor the drive train on the 350z may not be able to hold up to high levels of instant boost. It’s not like the centrifugal type compressor where the boost will build up with RPM, instead you will see full boost instantly. When you have full 7-9 psi of boost kicking in at once, this seems like it will put a lot of strain on some of the drive train parts. But, in all honestly I think the main reason will have to be the Heat issue.

Procharger can set the boost levels fairly high because they are using intercooled boost. You have to remember this is a high compression engine. With high compression engines you see more heat. When you intercool boost you have a better chance of controlling detonation.

 

I should've said,"not getting as much air".I can't quote any numbers, but the air flow tends to be better in the cylinders closest to the opening of the plenum.Crawford Z opened up the front of the manifold to somewhat even out the pressure.Read the threads here or the other forum,I'm not sure.In one of the threads it mentioned to check your spark plugs.I'm also not sold on either SC, both have up & downs.I think I'll wait to see how the first few go.

 

Weslutes - in the SPortZ video stillen says they have a diffuser in their plenum. That should make the air distribute evenly. Wouldn't it? Then you would be feeding the cylinders the same all around....

I don't know which to get. I want the warranty and the carb certificate but also like the idea of the bigger horsepower. With my luck, I'll put the centrifugal on and blow up the motor! No warranty - no fixy the motor.

 

I can't seem to play the video with my iMac. But you said Stillen has a diffuser in the SC?Please explain.

 

Yeah, the Sport Z Magazine Video shows the insides of the intake plenum that comes with the blower kit and you see the defuser plate that the stillen says evenly distributes the air to all 6 pistons.

 

Stillen is working on new pulleys and a water to air intercooler that sits under the S/C. I wonder how well that will work and cost.

 

Thats very interesting, ATI says water to air intercoolers only work well with marine applications and they've done a lot of them.