Hey guy, I'm interested in your thoughts as to the exhaust system that I'm proposing for my street/strip 572" , 11:1 CR Hemi A body.
We know Hemis dont like restriction much but a little may be needed to shut this thing up to respectable/legals levels over here.
The Hemi made 845HP at 6500 rpm and 770TQ at 5300rpm. THE challenge is to keep the cars noise under 96dB at 3500 rpm (a tall order,we have strict noise regs here) when tested without choking it yet allow decent breathing for street use. At the track it will be uncorked a distance after the collectors anyway.
I have TTI 2 1/4" primary tube headers with 3.5" collectors. The TTI collectors leave a bit to be desired IMO so I may cut them off and add merged collectors - we will see.
The tank is a FUEL CELL in the trunk so I have the extra clearance at the car's rear for a second set of mufflers.
The round header collectors gradually merge into nice 3.5" oval tubing (for good ground clearance) with a nice radiused X crossover, oval in/out. After the X/before the rear end I may/may not add a pressure wave termination box if I have the room. If not, I will likely run 3.5" inlet/3" outlet Dynomax Ultra Flows and reduce to 3" mandrel bends over the rear end then to dual 3" in/out Ultra Flows just before the rear bumper.
Having the mufflers right at the end of the exhaust will further quieten it. I know the flow specs of the mufflers will do the job and im looking at stepping it down to 3" over the rear end to the back of the car as the gases will have cooled after the first set of mufflers and the 3" pipes will be a little quieter I believe along with allowing for room for other components.
How loud do you feel this system may be (hard to guess i know) and do you feel that long case Walker Super Turbos instead of the Ultra Flows (I think a 16" case should fit length wise, if there is room poss an 18" case) would flow enough on the street yet keep the car relatively quiet. I will have header dumps added when I've figured out exactly where to put them for the strip and to maximise pulse tuning.
I'd appreciate your thoughts/input as I'd like to find the right mufflers the first time (Im in Australia) and order them soon.
Fire away fellas....... :glasses7:
We know Hemis dont like restriction much but a little may be needed to shut this thing up to respectable/legals levels over here.
The Hemi made 845HP at 6500 rpm and 770TQ at 5300rpm. THE challenge is to keep the cars noise under 96dB at 3500 rpm (a tall order,we have strict noise regs here) when tested without choking it yet allow decent breathing for street use. At the track it will be uncorked a distance after the collectors anyway.
I have TTI 2 1/4" primary tube headers with 3.5" collectors. The TTI collectors leave a bit to be desired IMO so I may cut them off and add merged collectors - we will see.
The tank is a FUEL CELL in the trunk so I have the extra clearance at the car's rear for a second set of mufflers.
The round header collectors gradually merge into nice 3.5" oval tubing (for good ground clearance) with a nice radiused X crossover, oval in/out. After the X/before the rear end I may/may not add a pressure wave termination box if I have the room. If not, I will likely run 3.5" inlet/3" outlet Dynomax Ultra Flows and reduce to 3" mandrel bends over the rear end then to dual 3" in/out Ultra Flows just before the rear bumper.
Having the mufflers right at the end of the exhaust will further quieten it. I know the flow specs of the mufflers will do the job and im looking at stepping it down to 3" over the rear end to the back of the car as the gases will have cooled after the first set of mufflers and the 3" pipes will be a little quieter I believe along with allowing for room for other components.
How loud do you feel this system may be (hard to guess i know) and do you feel that long case Walker Super Turbos instead of the Ultra Flows (I think a 16" case should fit length wise, if there is room poss an 18" case) would flow enough on the street yet keep the car relatively quiet. I will have header dumps added when I've figured out exactly where to put them for the strip and to maximise pulse tuning.
I'd appreciate your thoughts/input as I'd like to find the right mufflers the first time (Im in Australia) and order them soon.
Fire away fellas....... :glasses7:
