a triplet of exhaust questions

[magnethead]

My friend (1984 C1500 305/350) had his exhaust finally rust off at the back edge of the cab (std cab LWB), so right now he's running with the cat and no muffler.

The exhaust shop in town quoted him 53 dollars to get a glasspack and to put new pipe from where it rusted off to a dump in front of the driver side rear wheel. Does that sound about fair? His truck has a VERY throaty sound to it (think boat with through-hull exhaust), so i told him to skip a muffler, save the 5 bucks, and get a glasspack. It'll quiet the loudness and keep the throat, right?

What is the year cutoff between emmisions and safety inspection? He has all the smog equipment, but being his is an 84, would it pass visual inspection (we dont have hook-up emmisions up here) if he removed the cat and smog pump? and Would it start throwing codes?


That got me to thinking, I have true duals with an H pipe. If I were to use all the factory hangers (keep the factory behind axle exit), what would best fit my 454? I currently have long tube headers and factory 2.25"ish exhaust. I'm not for sure what the collector size is on the headers, i'd imagine 2.75", about how much would it cost for a pair of glasspacks and all new pipes that size-match the collectors? (crew cab LWB) my truck is non-SMOG.

Would I be better off buying the metal, and fabbing it all up myself, to rid the labor fees?

[49studebaker]

Glass packs are cheap, some cheaper than others, but it sounds like a good deal to me. I'd climb under there and do it myself if it were mine, not that I'd save a lot of $$. Yours would take a bit more 'cuz it includes bending the pipe. I'd think $150 wouldn't be a bad deal. I don't know what labor rates are like in Tx. I plan on doing my own on my 71 GMC from the collectors back. I'll buy the prebent pieces and cut, weld, etc. I don't think I'll save much but I want the satisfaction of building my own truck. JMO

[magnethead]

Well my friend has to have his bent too, as he's going from the factory Y pipe under the tranny to a side exit in front of the rear tire.

my exhaust is fine as it is, but 2.25" pipes have GOT to be restrictive to the motor. I don't want to rid all the backpressure (for sake of the valvetrain), but i just want to get pipes that match my collectors.

[magnethead]

my friend had it done, i went with him.

They hacked his pipe right after the Catylitic, shined a flashlight up there, and the cat is hollowed out already. He got a 18" glasspack and a turndown right past the back of the cab.

Yet it seems wierdly quiet- I couldn't even hear it while it was idling, and i had my head halfway up the rear fender. Wonder how it sounds when he's on it (can't really do that on city streets)

[craig@ridetech.com]

I am considering 2 options for my 76. I am either going to run a set of those purple hornies with the 3" turndown bolted directly to the header and be done with it or run some 3" off the headers back to a couple of 40 series Flowmasters with turndowns. Both are easy and realtively inexpensive to do. Plus the Flowmasters sound mean as hell. We did a car here with those 40 series on it and it sounded badass, it just shook the whole shop with a mildly built 400 pumping through them.

[magnethead]

if you run purple hornies, it's not street legal.

inspection requires that the exit be past the rear edge of the cab.

[lurch115]

i have dual 3" on my '84 4x4...and even though i was able to get my tubing bent for free it still cost me about $300-$350 from the motor to the back of the truck....but on the upside of that...from the headers (3"collectors are the common, which is more than likely what you have)back the smallest opening is 3"...but in iowa they don't check vehicle emissions...(yet) so i didn't have to put cats. on....i went with TRUE Cherry Bombs...now on a 355 running at 9.5:1 compression its right at the db. level for the law at idle...but if i touch the pedal its illegal...thats the joys of having an old beat up looking truck...they think i am a farmer and leave me alone....

[magnethead]

Originally Posted by lurch115

i have dual 3" on my '84 4x4...and even though i was able to get my tubing bent for free it still cost me about $300-$350 from the motor to the back of the truck....but on the upside of that...from the headers (3"collectors are the common, which is more than likely what you have)back the smallest opening is 3"...but in iowa they don't check vehicle emissions...(yet) so i didn't have to put cats. on....i went with TRUE Cherry Bombs...now on a 355 running at 9.5:1 compression its right at the db. level for the law at idle...but if i touch the pedal its illegal...thats the joys of having an old beat up looking truck...they think i am a farmer and leave me alone....

would that be a 6" glasspack?

He had a few of those on the shelf but they were used. My truck was never smog equipped, so i'm clear there to do what I want.

[craig@ridetech.com]

Originally Posted by magnethead

if you run purple hornies, it's not street legal.

inspection requires that the exit be past the rear edge of the cab.

yeah, luckily where I live they never check that stuff either. As long as I don't cause any trouble I'll be ok.

[49studebaker]

The only problem I have with my exhaust ending right behind the cab is at times they resonate so bad, you can't here anything else. That is just at idle though.