Thanks the for nice comments guys.
ST,
I think I've just about got it under control as long as I can keep everything from moving around while I weld on the 1-7/8" primaries and the collectors
. The final matter will be building the collectors, as I haven't been able to find any that fit the tubes properly. The ones in the pictures were dented pretty poorly when I received them, but for $12 each, they worked great for fixturing everything while doing the rest of the work.
Siz,
I'm either going to put a pair of O2 sensor bungs in the collectors or in two of the primaries closer to the head. Probably the later so I can get a more accurate measurement. I don't think I need EGT bungs, as the engine is pretty mild and I think I can tune it well enough by monitoring the AFR and reading the plugs. Yes, they will be ceramic coated when we're done.
Tim,
I thought about that for a long time before deciding to go this unconventional route. I didn't have room for the 4 into 4 flange like EM or Enzo sell due to an extended drv's side footbox. And I didn't want slip fit joints as I felt they would eventually leak and wouldn't provide the support I desired for the sidepipes. And I wanted a way to replace just the muffler section if I don't like the sound or am not happy with the performance. This method meets all those requirements and guarantees no leaks with the 3/8" thick 3 bolt flanges I made. With the car jacked up about 10" (ie normal working height in our shop) the headers drop right out very easily in about 5 minutes each side. So I'm real happy with this configuration.
Kountz,
My old pipes had 2" primaries but they were just too big for my little 2V motor
. How do you like the Cermachrome coating?
Great Asp,
Those certainly sound like a nice set of pipes. I went with mild steel for the price and since it will run cooler than stainless once they're coated (at least, I hope
). I'm sure that 418 likes those 2" pipes too. That must be one scary ride! I also didn't personally care for all the sidepipes that have the perfectly matched bends on the sidepipes where they pass though the body. Hence I ended up with something closer to the Harris sprint car style arrangement if you look closely.
Mike