I have a 2012 SRT8 and the internal diameter of the exhaust tip is narrower (smaller hole) than the exaust pipe itself. To me it looke like the SRT8, that uses larger pipe than the RT, uses the RT Exhaust Tip. the difference is 1/4". Am I crazy or is this a restriction?? Did Dodge cheap out on thsi and not make a correct sized tip?? Is the optional Mopar Tim larger??? I cannot find any aftermarket ones.:SM030:

It may not seem as "normal" as if they just made it the same size, but it's probably a negligible effect in the Big Picture. You have to account for the exhaust gas contracting a bit as it loses heat the farther it goes down the pipe. By time it gets to the tips, it occupies less volume than when it came out of the engine. So the size reduction is actually a measure to maintain exhaust velocity to the very end of the pipe, which is typically a good thing for exhaust performance.

Than why use larger diameter pipe on the SRT8 than the RT? (2.75" vs 2.5") I am sorry but in my experience it is a restriction and affects power. Honda and others make dirt bikes with a bolt in restrictor in the exhaust to meet noise requirements for some areas. You can simply remove the tip and it gives noticeably more power. If they wanted to maintain exhaust velocity for scavenging, etc. they would use smaller diameter pipe overall, not put a small tip. It is in the details that my disappointment in Dodge comes out. They sell optional Mopar Tips but I cannot find out of they have a larger ID or not. The real surprising thing is this is the 1st and only post about this issue. I am surprised that no one in the aftermarket exhaust arena has come out with an option. Might even change the sound, who knows. I am not saying it will help power or not, but surely it is worth trying a car on the dyno with and without tips installed.

An SRT8 is a bigger engine than the RT, and revs to a higher redline, as well. The larger pipe size is there to accommodate that greater flow on the top end. That doesn't change the fact that exhaust gas cools by time it has traveled down the length of the car in piping, and the piping requirements are consequentially ever so slightly less at the very end. If the pipe is sized for optimal flow at the manifold end, then that size becomes increasingly in excess the further back you go as the gas cools. So there is no sudden "restriction" as you surmise from a slightly smaller exhaust tip. It's probably right where the pipe size would be had it been sized for the flow of the exhaust in that very temperature state. In short, don't sweat it so much! ;) Its not like a everything is pivoting around the end diameter needing to be exactly equal to the start diameter, because the thermodynamics are hinting at a slightly decreasing diameter as the exhaust travels further away from the engine (or catalysts, if you want to get technical) to maintain flow velocity. They don't make pipe with variable diameter, so a smaller tip at the end is probably the next best thing to that.

Plain pipe can flow quite easily. It's the details of the mufflers that should be the focus of restriction mitigation.

An SRT8 is a bigger engine than the RT, and revs to a higher redline, as well. The larger pipe size is there to accommodate that greater flow on the top end. That doesn't change the fact that exhaust gas cools by time it has traveled down the length of the car in piping, and the piping requirements are consequentially ever so slightly less at the very end. If the pipe is sized for optimal flow at the manifold end, then that size becomes increasingly in excess the further back you go as the gas cools. So there is no sudden "restriction" as you surmise from a slightly smaller exhaust tip. It's probably right where the pipe size would be had it been sized for the flow of the exhaust in that very temperature state. In short, don't sweat it so much! ;) Its not like a everything is pivoting around the end diameter needing to be exactly equal to the start diameter, because the thermodynamics are hinting at a slightly decreasing diameter as the exhaust travels further away from the engine (or catalysts, if you want to get technical) to maintain flow velocity. They don't make pipe with variable diameter, so a smaller tip at the end is probably the next best thing to that.

Plain pipe can flow quite easily. It's the details of the mufflers that should be the focus of restriction mitigation.

This is Dodge we are talking about and FWIW, your theory is a good one but the reality is, Dodge will not create two differently sized tips even if it did matter because the been counters said NO! :scratchhead:

There are YUGO quality components on this car (for the 50k price tag) and it shows the bean counters are in control at Dodge. :notallthere:

They sell optional Mopar Tips but I cannot find out of they have a larger ID or not.

I bought those Mopar quad tips off a guy who had an '11 IE 392 and they fit perfectly on my stock '10 R/T.

Did the Mopar Tips have a larger id?