[MaSnaka]

A little follow up if anyone remembers this thread.

Rick your idea about shiming the air cleaner with stacked up gaskets got me to thinking...I know it's a chance I gotta take once in awhile (thinking that is). I used 1/2'' rubber weatherstripping with an adhesive side from Home Depot and used it on the aircleaner base and lid. This compressed gave me a total 1/2" gained clearance above the choke horn.

New intake manifold, Edel Performer RPM replaced the Edel Performer 390. The carb base sits about 1/2" taller and 1" further back than the 390 perf. Reducing the carb spacer to 1/2" keeps everything under the hood.

New mufflers installed into my existing CR side pipes. Classic Chambered 2 1/2" x 30" with louvers open to the exit side. Deep loud sound. Yes my ears hurt but they tickle my ribs and make me smile.

Ok here we go. Pipes are coated and back in place. The only changes made are Edelbrock Performer 390 (basically a stock intake, aluminum) was upgraded to a Edelbrock Performer RPM and I replaced the original CR mufflers with Classic Chambered's 2 1/2" core x 30" Cobra packs (louvers open to the exit side). With no air filter in place, the original intake and mufflers, tuned at the dyno was max output at 253rwhp and 320rwtq. With no air filter in place, the new intake and mufflers, tuned at the same dyno was max output at 305rwhp and 361rwtq. A fantastic improvement and experience. The mufflers that I replaced had 1 1/2" dia. x 24" perforated tubes offset inside the muffler body. Basically my car was trying to exhale through two straws. The max numbers tell one story but the curves tell an even better one. At 4500rpms I gained over 60rwhp and 70rwtq with a much flater tq line from the low end up through 4600rpm. Stock 390 with 280H cam, Performer RPM intake, stock iron heads, Holley 750 street avenger, and headers.

News flash. The Holley Street Avenger is a 770cfm not a 750. So instead of going with the HP series no choke horn carb which is not availible in 770, I am going to mill the choke horn off my current carb. This saves me another dyno trip to rejet and a few hundred bucks. I will save my quarters so I can upgrade the heads and the carb at a later time.

Thanks to all who contributed their knowledge to help me. The results are quite satisfactory.

John