Bosal Headers Page 2 of 6 Bosal header components Bosal headers ports Stock header ports and components October 1998 1 have recently installed Brospeed headers (a subsidiary of Bosal USA, Inc) After I purchased them. 1 contacted Bosal (with the help of Strano Performance) to see if they were interested in sponsoring my planned before and after headers dyno testing. Bosal was also quite interested in working with me to compile the dyno data with Brospeeds. So they offered to run the before and after dyno data including the header installation and a test report (for free) at their Bosal R & D facility in Ann Arbor, MI, Thanks to Dan Brown, John Herman, and Greg Nilsson of Bosal for their efforts and hospitality during the testing! Additional Probe GT Dyno Data: Also a friend of mine at work has provided her stock 1996 PGT to Bosal to determine the feasibility of developing headers and a catback exhaust that will t the OBD-II 1996/1997 models too, They are also running before and after data on it as welli Dev Saberwal brought had his car with Hotshot Gen. 1 headers (with a Hennessey exhaust, no cat, open conical K&N, and a Superchip) dynoed at the same facility for comparison purposes Lastly another friend may be taking in his 1994 PGT with Pacesetter headers soon! Below is my recap of the dyno testing that Bosal rant See the to see their actual report Test Congurations They tested my car with the following congurations: 0 As received condition (Hennessey exhaust, my K&N, homemade airbox/scoop assembly, etc.) a They removed the Hennessey and installed their Brospeed full catbackexhaust system 0 Installed my Brospeed headers (with my Hennessey reinstalled) 8 Lastly, I removed my homemade airbox and ran with just the open K&N lter. I was observing the K&N data in real time. No surprise - I lost 3 HP with it exposed You need to enclose your K&N lters! A11 conditions were at least four runs with a cool down period in between runs. Quoted data is the average of said runs. General Power sweeps were performed on a Clayton electric chassis dynarnometer which actually measures wheel torque via a calibrated torque meter. This is much more accurate than the calculation method that DynoJet dynos employi Clayton dynos are roughly $160,000 as compared to $20,000 for a DynoJet. There was about a 26 lbr difference between the Bosal and some previous DynoJet data All data were corrected to SAE J 1349 specs The vehicle radiator fans were run continuously First off. the Hennessey rules in power. However, the Brospeed system showed a net loss of only 0.2 to 2.2% (1 to Z LB) from my Hennessey mufer although it was considerably quieter A stock mufer was not tested (yet), The Brospeed system is a 3-pass mufer design (about 2/3 the size of the stock can) with twin tips versus the straight through design of my Hennessey. The sound pressure level of the Hennessey exhaust near the tip at 6000 RPM WOT was a whopping 105+ decibels! It would be even louder at lower RPMs where there is a more bassy note. http://www.mtco.com/~westcj/Brian/bosa1.htm 10/27/2001