Thread: 355 sbc question about exhaust sound (need some help here!)

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After cooling off a little im gonna give this another chance. comment that has all the info on it is on page 5 with a link in it.

I didn't hear anything bad.. but, the video is at the wrong end of the car!

OH, welcome to CHR too. Good to see you here and hope you enjoy the site and the folks.

Your profile shows New York. the plates show Canada...

Originally Posted by 34_40

I didn't hear anything bad.. but, the video is at the wrong end of the car!

OH, welcome to CHR too. Good to see you here and hope you enjoy the site and the folks.

Your profile shows New York. the plates show Canada...

K thank for the reply I would get a another vid of the engine bay while it was running but it is tucked away for the winter because we got a couple feet of snow here lol. and as for the fact ti says new york when it asked for where i was it said sate and there aren't states here in canada..................

I agree with Mike, put your camera/mike up front, focused on the engine. The exhaust sounds OK with a healthy idle, but the exhaust note drowns out any engine sounds that might point to problems. Also, after your 45 second clip it rolls into a longer clip about a red '82 which is a different car, right?

Welcome to CHR.

Sounds good to me, but since you don't know much about the internals I think I'd keep the shift point at 5 grand or below.

Welcome
JMHO, it sounds like back pressure, possibly a leaky exhaust gasket/joint, or a loose muffler baffle..

Originally Posted by 36 sedan

Welcome
JMHO, it sounds like back pressure, possibly a leaky exhaust gasket/joint, or a loose muffler baffle..

Im surprised you could hear that in the vid!!! The front right header comes a little lose on its own every so often so i need to tighten it once every 1 or 2 weeks until i can afford to buy 2 new hooker headers.

Originally Posted by Tie-355

Im surprised you could hear that in the vid!!! The front right header comes a little lose on its own every so often so i need to tighten it once every 1 or 2 weeks until i can afford to buy 2 new hooker headers.

Before you go buyin' headers, there are a couple of different ways to stop header bolts from coming loose. If that is what's happening, let us know, we can share info to help keep the header bolts tight.

Originally Posted by 34_40

Before you go buyin' headers, there are a couple of different ways to stop header bolts from coming loose. If that is what's happening, let us know, we can share info to help keep the header bolts tight.

I suspect they're cheezy headers with 1/4" flanges that bow up from the heat of exhaust and allow leaks. Anyone buying headers should look for minimum 3/8" flanges and if somebody made headers with 1/2" flanges, I'd buy 'em.

.

Originally Posted by techinspector1

I suspect they're cheezy headers with 1/4" flanges that bow up from the heat of exhaust and allow leaks. Anyone buying headers should look for minimum 3/8" flanges and if somebody made headers with 1/2" flanges, I'd buy 'em.

.

I will tell you my new best friend in preventing leaks and they are cheap...Nord lock washers, you can use them with your existing bolts and they are reusable. They sell them buy various other names through header manufacturers for a ton more money, but you can get them individually at Fastenal in stainless steel or steel. I put them on and have forgot about them, never had to tighten them again. I talked with a header rep that has some EXPENSIVE fancy products (expanding bolts w/a recessed set screw) and he said, come over here and behind therir booth he said, "Use the Nordlock and save some money" that was at a NSRA event. I also used them on the collectors and not a leak yet, I literally tried about every other option including saftey wiring and these work the best & the cheapest I have found (my opinion only)
https://www.fastenal.com/products/de...+Washer%2FPair
(thats the retail cost, you can get them cheaper if you have an account)
Google Nord lock to see how they work

Originally Posted by 34_40

Before you go buyin' headers, there are a couple of different ways to stop header bolts from coming loose. If that is what's happening, let us know, we can share info to help keep the header bolts tight.

will do man!

Glad you enjoyed Denny,
Maybe just my ears, but I'm hearing a rattle on the reversion...

JMHO, but I think that what you're hearing is harmonics and the baffling in the mufflers.

Originally Posted by Tie-355

But the question i have is If the car should sound the way it does when reved to around 5000 rpm.

As the above question asks,
To me it sounds like a little back pressure as it comes off throttle, it doesn't mean a bad thing. However, my old ears hear a slight rattle at reversion. Thus the suggestion to check for a loose baffle and/or small exhaust leak, both of which are easy to do.
Not trying to be funny, certainly no disrespect intended, and it may just be harmonics as suggested...

And I believe that resonators behind the mufflers would probably cancel some of it out though I sure wouldn't want to do that.