| Well, now I wish I had made a few pulls with the previous exhaust before last night's pulls. All I will say is that the results are not comparable. Last night when we were making a few pulls it dawned upon me that there are some things that have changed since the dyno pulls back in 06. I removed the electric water pump around 40K miles and made up a new set of VTC's. The VTCs are likely where the biggest difference is occuring as I do remember advancing the intake cams a little back in 06. What I plan to do at this point is I still want to lower the sound level in the exhaust - it is a touch quieter, but I'm still not happy with the drone. I will be cutting out the section I just built and installing flanges to re-attach it. I'll get my hands on some inexpensive steel tube and steel flanges to build straight sections to return the exhaust back to its original design. I'll also pick up enough parts to build an H pipe section. In the end I'm going to play around with installing tow butterfly plates into the pipes coming out of the new silencer and use an pneumatic actuator to open/close them. Should be able to add in a little flow restriction downstream of the silencer so it can quiet things down a bit for manifold conditions under 0psi, and then open up at the onset of boost. I have to cut this section out to build these parts so what the heck, I'll make up a straight section and an H pipe and test all three. As for the dyno charts, at 4000RPM the new setup is showing about 10HP less but on the top end it is producing more. I think this is a result of non-identical intake cam timing. I also think in the previous dyno the controller was spiking a bit as the torque curve has a double hump in it while the new setup has a nice linear slope after 4000RPM. No apples to apples here today my friends. I'll post back on this once I get the new parts built and do some more testing. Also, I know a lot of people, including myself, always want to see A/F and boost pressure. Unfortunately at the moment we do not have this module installed into our dynojet. Both of these dyno charts are at 1.35bar and 11.5:1 mixture. When I do the next round of testing we will have this new module hooked up. This is the old dyno from back in '06 with the original exhaust setup at 18psi, 93 octane:
 This is the 18psi 93 octane chart from yesterday evening with the new configuration:
Enthusiasts soon understand each other. --W. Irving.
Are you an enthusiast? If you are out to describe the truth, leave elegance to the
tailor.
Albert Einstein
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