1990 Exhaust Restriction

[lstreich]

So I lived with the exhaust hissing at me on acceleration for several years before I parked it. I believe it is the muffler however it could be cat or something in the tubes. As I wrote it is hissing not banging like a broken cat baffle. Been there, done that, even a rookie with less TIG than me can hear the difference. It had no problem passing smog here in the Socialist Republic of California. My question(s) is/are: is there a definitive test to locate any obstructions upstream of the muffler aside from pulling the whole damn thing off? I guess I could yank the muffler, gut it, and see what comes out.

Also on a side note, if I replace the muffler I want something open throated and nasty. Any recommendations?

Leo

 

[Landyr67g]

So I lived with the exhaust hissing at me on acceleration for several years before I parked it. I believe it is the muffler however it could be cat or something in the tubes. As I wrote it is hissing not banging like a broken cat baffle. Been there, done that, even a rookie with less TIG than me can hear the difference. It had no problem passing smog here in the Socialist Republic of California. My question(s) is/are: is there a definitive test to locate any obstructions upstream of the muffler aside from pulling the whole damn thing off? I guess I could yank the muffler, gut it, and see what comes out.

Also on a side note, if I replace the muffler I want something open throated and nasty. Any recommendations?

Leo

Very late reply to this........I have a 1990 5.8 here in California with orig cats (one behind the other). My original rear muffler and twin pipes were rotted so I replaced the muffler with an 18 or 22 inch body (need to check) sized for 3" pipe. The shop could not make a 3" pipe work on my stock height truck so got a single 2.5 from muffler rearward. Its not too loud but definitiely noticeable. That said, I think the bigger issue is the cheap hangers that were installed. Make sure to invest in rubber loop style - not the tiny hard clamped rubber blocks. Those transmit alot into the chassis and body.
Regards,
Joe M

 

[L\Bronco]

So I lived with the exhaust hissing at me on acceleration for several years before I parked it. I believe it is the muffler however it could be cat or something in the tubes. As I wrote it is hissing not banging like a broken cat baffle. Been there, done that, even a rookie with less TIG than me can hear the difference. It had no problem passing smog here in the Socialist Republic of California. My question(s) is/are: is there a definitive test to locate any obstructions upstream of the muffler aside from pulling the whole damn thing off? I guess I could yank the muffler, gut it, and see what comes out.

Also on a side note, if I replace the muffler I want something open throated and nasty. Any recommendations?

Leo

Hey Leo, sorry for the delay, I've been in the states drag racing. the best test would be a back pressure gauge screwed into the O2 sensor hole, make a measurement at 2000 rpm (Should be below 1 psi), then remove the muffler and retest. That should tell you if its the muffler or ahead.
Hope that helps
Cheers!
P.S. I put a 3" magnaflow on my FrancenBronc and it sounds sweet. Nice growl, a bit raunchy at WOT but not obnoxious.
Cheers2