Re: where to buy raw exhaust pipe and fittings?
I like to buy locally too, but when it came to exhaust, you just can't find a lot of stuff without resorting to the net.
My local jobber brought me in that Dynomax mandrel bent 2 1/2" tailpipe. He also let me sit at the counter with the whole Walker catalog(and price list) and hunt through it for the bbest fit and best bargain.
They were able to order the Walker header flanges, but J.C.Whitney were cheaper, I use both. Both are just plate, like you say, but the bolt hole centers are critical if you plan on using header gaskets.
No there's nothing tapered about the flanges, you just slip them over the pipe (or put the die grinder to them to make them fit over the pipe) clock them (for positioning for easy bolt access) and tack away with you mig.
Yes you're right, the two free(un-welded) ends press together to seal. Make sure you clock them right so you can gain access to all three bolts and nuts.
I use not only Mr.Gasket Ultra seal gaskets(less than $5.00 American a pair), but my mechanic buddy told me to smather them with that high heat permatex gasket goo. He was right cause they've never leaked.
I don't buy the cat theory either, but as of two years ago, our province has started testing vehicles for the first time ever. luckily for me my Bronco will be permanently exempt from testing after July as it'll be too old to test.
Woo Hoo a free pass !
There's nothing says you have to use header flanges and gaskets, heck there's newer joining methods, like the clamps you showed me, but I like header flanges for a few reasons.
1.) they actually add strength to the Flowmaster Y pipe and take the brunt of any twisting or beating you give the pipes later to get them apart.
2.) You can keep taking them apart and putting them back together over and over again really easily, as you try different mufflers, cat test pipes, etc. Try that with slip fit conventional muffler connections.
3.) They're really cheap and you can get anybody's brand gaskets in Nowhereville, USA or Canada.
As for a decently quiet muffler, check out that universal Walker truck muffler I got. It was priced the same as the Dynomax tailpipe(cheap) and it's fully welded construction.
After I stuck it on, nobody would believe me anymore that it was a 302. It ain't loud, it just has a very deep, low rumble. When my Dad heard it he said it sounded like a truck, now that's what you want !
The real key to the system is that Flowmaster Y pipe, to which you just add a flange on one end and the two headpipes into the other end. At $34.00 you can't beat it !
With a little planning, you can see the easy access we got between our crossmembers to all flanges and fasteners and tha major ground clearance picked up.
Thank again to WD-40, whose system it's patterned after.