stingry

Any idea how to quiet this down?

Heres what I have:

Rebuilt 1970 350Ci bored .030 over.
Computer balanced. (the engine is balanced)
New 1970 350CI L46 CAM
1970 Double Hump heads with new 2.02/1.6 valves port and polished
Intake gasket matched
1970 Ramshorn exhaust manifolds
Stainlessworks dual stainless exhaust system 2" at manifold then 2&1/2 inch all the way to mufflers then 2" tips. Original style stainless mufflers with extra packing. I had this same system on my car before the rebuild and is seemed quiet (with a rumble) to me.

Car is very loud. It has a lope (from cam) and if revved past 3500 is very noisy. I want to try and keep the exhaust system as is but add to it inline or ...???

I know I cannot fix the lope but how can I make it more neighbour friendly?

Am I doomed to noise because of the cam?

Help!!!!

:rolleyes:


[Modified by stingry, 11:14 AM 5/4/2004]


[Modified by stingry, 11:15 AM 5/4/2004]

73 Vet

How did the system fit? Did it "bolt right up?" About the noise, are you serious? :cheers:

Corey_68

Throw in a 4cylinder. :D :leaving:


[Modified by Corey_68, 4:16 PM 5/4/2004]

stingry

Except for the RF pipe it all fit well. I had to cut and flip half of the RF pipe to get clearance from the floor.

Quality is good and everything is mandrel bent.

zwede

A few ideas:

1. An H or X pipe will make it a little quieter.

2. Dynomax makes inline race mufflers that are only 4" diameter that can be fitted under the seats.

3. You can try a set of 19" long Borla mufflers. I have a set on my 454 and they are fairly quiet.

wcsinx

:iagree: I think especially if you're blaming the noise on a lumpy cam.

LiveandLetDrive

:withstupid:

I'm sure you can get a good deal on a Camry... or a Volvo.

Schmucker

You shouldn't be taking it past 3000rpm in a neighborhood anyways. It really shouldn't be a problem. You shouldn't be trying to please them anyways. How do YOU like the sound?


[Modified by Schmucker, 12:57 PM 5/4/2004]

L79vette

That's not a big cam, really. Large cam shouldn't make it noisier anyway, at least not significantly.

If it is really noisy, maybe you have an exhaust leak. Maybe a joint that gaps open under high flow but normally seals due to clamping forces.

Madmikeee

Just do What I did, Go down front beach road with your headers uncorked, The cops and hooters girls LOVE that :)

The really liked it when I did a burnout in my 68 camaro with open headers. They wanted my autograph and everything.

Jay M

Maybe the mufflers are worn out... I wouldn't think it should be loud at all. Maybe a better stock replacement muffler would be quieter.

~Jay

Schmucker

That was your signerature on the ticket, not an autograph ;)

Madmikeee

:D

stingraymaniac

noise whats that??
fired my car up this weekend with open headers...
thats the way they should sound!!!! :D
but i think my neighboors gonna shoot me :D

stingry

zwede,

Thanks.

I am going to adjust/tighten everything and then see if it makes a difference. Then I will try and build a custom X-pipe out of rectangular stainless (if it exists) to fit under the rear end. I don't like where the exhaust runs there anyway. I would like the exhaust higher and clear of my composite spring. If I manage to fabricate a "flat" X-pipe then I should be able to do both.

I am also going to tune the engine and check for vaccumn and exhaust leaks...

stingry

Sound is too noisy. It is heaps louder then before and the exhaust system has less then 500 mile son it. The mufflers are the same manufacturer as who made the last set (they blew up due to backfire) and they sound a LOT louder.

In short too loud for me or my neighbours and the exhaust is virtually new.

stingry

Thanks L79vette. I am checking for leaks now.

I didn't think it was too big a cam either.

It is more of a "drone loud" then if you had say headers. I think I have a resonance problem more then anything. I am hoping I have a leak and I can find it. Once I get an X-pipe that will change the resonance frequency and should help there too.