As we are always trying to improve on our 70 Challenger convertible, we recently installed a factory exact reproduction exhaust system that is in every shape and way exact down to the smallest detail. Personally, I think that these would look like NOS pieces if they aged a little as they seem to be that good and correct ! We removed the Accurate Exhaust Ltd system we had on the car which was on there for about maybe 5 years and lucked out in taking everything off without having to cut or torch anything of the old system trying to get it off. Some PB blaster and a rubber mallet and everything worked there way free. Below are some comparison pictures I took noting the differences between the two systems. See which one you think is more accurate !
First pic is of the mufflers that are behind the rear axle. The differences here are major ! The muffler from Accurate has a shorter length and is also a smaller diameter. Also note that there is no flat indentation for clearance where the tie down hooks would go on the unibody. ECS mufflers also have the approved Chrysler Pentastar, date codes, and even the vendor codes stamped into the mufflers like the factory ones did.
One other thing that I like is that the over the axle pipe is welded onto the muffler like the factory did it with the ECS exhaust. The Accurate system was clamped here which had soot coming out of the exhaust and onto the rear axle getting it dirty. I might be wrong, but Accurate could do this now also but for an extra cost.
A couple more differences between ECS' muffler vs. Accurate is the hanger bracket design. ECS' is boxed in vs. the Accurate design being open on the sides and having threads tapped into the lower part of the bracket to bolt up the S hanger. Also notice the slots in the pipe on ECS factory design vs the closed pipe in the Accurate design. This will certainly make it easier to get the exhaust tips out should you need to replace the muffler at any time. One other VERY important difference is the absence of the weep hole in Accurate's design. Without this hole water will build up and speed up the deterioration inside the muffler causing an earlier failure of the muffler. Another small detail is the spot welds on the pipe that exits out of the muffler on the ECS model. The Accurate example appears to be crimped in by expanding the pipe inside of the end plate.
inside tube of Accurate's resonator design. Notice the round perforation holes and the crimped style where it seems like the pipe gets constricted at areas?
The factory design, which is replicated by ECS' design, has the square perforations and you can also see the spot welds that hold the pipe to the end plate. Also, no constricting of the interior pipe causing a flow reduction. Lack of spot welds holding internal baffles in place.
Stamped markings on Accurate's resonator, Lack of spot welds holding internal baffles in place.:
ECS' resonator has the factory spot welds to hold the baffles in place so they don't come loose or rattle and also has the Chrysler Pentastar as well as the date code and vendor code.
side by side comparison. (ECS on top, Accurate on bottom):
Accurate's driver side head pipe had some clearance issues when we went to install the system. After a call to Accurate we had to crush in the pipe to clear the torsion bar. Supposedly, I was told that the factory version had a crushed area here for clearance of the torsion bar. The reason why Accurate's header pipe did not have this was because they said there was just enough clearance with about a finger thickness to fit in between the torsion bar and the exhaust pipe so that is why they did not crush this area in. Since we have had our chally, I have found this to be in-accurate on factory pipe examples. The factory examples did not have any crushed areas and with the ECS header pipe which was copied off of an original factory pipe, we have plenty of clearance without having to "crush" the pipe. You can also notice the slight difference in the shape of the area of the pipe. This little bit of change seems to be what was causing the issue. Again, since we crushed in that area, we were able to solve the clearance issue. For those that might be wondering, to our knowledge, our challenger showed no signs of being in an accident.
Accurate pipe in front, ECS pipe in back:
Notice no clearance issues with the ECS header pipe installed !
Top - ECS pipe , Bottom - Accurate pipe:
Left- ECS pipe, Right - Accurate pipe:
Front - ECS pipe, Back - Accurate pipe:
Hopefully this helps some people make their decisions easier when you go to purchase an exhaust system. Don't get me wrong, Accurate Exhaust systems are a good system and were probably one of the best at the time. However, the ECS system I find is highly superior to the Accurate system we previously had on the challenger. Our car features a lot of factory correct details so the ECS system compliments the car nicely and just enhances the other details of the car. In the end, it all comes down to what YOU want to do with your car and what kind of look you are trying to achieve.