I just wanted to pass this along for you guys that do your own exhaust work. I am in the process of bending up a new exhaust system for an o/t F body gm car. The customer wanted to put magnaflow mufflers on it so i ordered a pair through Summit racing. The part # is 11235 which is 2 1/4 inlet and outlet. The first pair i got i went to install and they flopped around on the pipe, so i called summit and explained to the customer service guy what i had going on, i am not sure he completely understood what i was trying to tell him but he said he would send out another pair that day which he did. i got them this morning excited to get this car done and off my hoist. Well as you can guess that didnt go as planned, these are exactly the same. the pipes measure 2.247 and the inlet/outlet measures 2.35 which is obviously is .100 bigger than it should be. That being said i dont like bad mouthing anything without talking to whatever company is behind it. So there was a sheet of paper inside the box with Magnaflows tech number on it. i called and talked to a "tech advisor" who informed me that Magnaflow considers what i gave him for measurements were within what they consider acceptable "manufacture's acceptable tolerances" so they really couldnt do anything for me. He did tell me that if i wanted to i could send them one of the mufflers and they would send them over to quality control to see if there really is a problem with them. I dont know about you guys but i have installed a lot of mufflers in my years of doing this and quite a few of them were MF mufflers and never had one that fit this sloppy and no one willing to do anything about it.
I just went through the same thing. I'm using slip fit connections with "long style" clamps to hold everything together. I expected the "1 1/4" muffler tips to slide into the expanded ends of my 1 1/4 ex tubing but not even close. I finally got some 1 1/4 stainless and welded new tips onto the mufflers so this would all work. I think Magnaflow takes their 1 1/2 mufflers, simply squashes the ends down a bit, and calls it 1 1/4, with the result that what should be a simple bolt on becomes a royal pain in the ass.
In red above - You "initial" explanation IS...somewhat lacking. I didn't get it either! BUT...your second explanation would have given the Summit guy at lot...more information, and he possibly would have understood that one.. Mike
Nothing that would bother me. But I weld all my joints vs clamping. Add one of this to your tool box. Problem forever solved.
Just me, Sorry to HI-Jack the thread,, I get the hype about free flow. The sound they put out makes me want to talk anyone out of using them. I know, you got gotta make a buck.
If he actually is "bending the pipe" every exhaust pipe bender I have ever used has a pipe expander built in to fine tune pipes in situations like that. Still those hand use ones don't cost much and work pretty decent.
I do in fact bend pipe. i have been for 35 years and just bought a brand new huth 2600 bender and also i have a hand held hydraulic expander to use under the car. so i do in fact have the equipment to "fine" tune the pipe. the problem with bumping up the pipe or welding the joints together is the next time it needs something done its a bigger problem. i think about what i am doing before i do it. also i called the customer before continuing on about just welding the joints and that was something he did NOT want done. He decided to use the turbo style mufflers that i keep in stock that are aluminized instead of stainless. Its funny i posted this to make people aware of something that doesnt work the way it is supposed to and tell you what the company had to say about it and all i get is a hard time about not knowing how to do pipe work.
Maybe it's industry standard on tolerances, my Dynomax Bullets seemed to fit a little loose over 3 inch pipe too.
Yes, the OP could expand the pipes to fit over the ends of the muffler. However, his point is that the tolerances of the product is pretty darn sloppy, adding to his labor, which either he eats or passes along to the customer. He posted to let others know of the pitfall of this muffler, not ask how to fix it.
Thank You cshades, for sharing that. Appreciate the input. You went through a lot to get a proper result. Good on you, for making your customer pleased
Thanks Tom, i was just trying to save someone else the grief. the mufflers i ended up using i had to wiggle back and forth to get on the pipes which is the way they should be not a 1/10 of an inch to big.
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