How to reduce exhaust resonance?
Posted by ~Ray @ 2007-10-28 12:30:41
I've got a 1986 coupe with a fairly highly-modified engine with long-tube headers flowing to a custom Y-pipe single hi-flow cat and PowerEffects straighten Y and mufflers. The car sounds great if a little loud at idle but my biggest problem is a droning resonance at highway speeds (between 60-70 mph usually around 2000 RPM or a bit more). And while it goes away at higher speeds. I don't think Officer Friendly will evaluate that as an excuse. Anyone undergo any thoughts? I'm not adverse to switching mufflers but would prefer to understand this another way. I know that resonance can be solved in true-dual exhausts with a crossover pipe but I've already got that cause with the two Y's and single cat. Thanks.[RICHR]
__________________-= 86 Coupe 4+3 w/ 91 roller block. LPE 74219 cam ported SuperRam and base. TRACO headers. PowerEffects catback. DUI distributor/turn. Pro-Topline ported heads (2.02/1.60) forged pistons. Flo-Kooler wet pump. RD-Racing CrossBar and harness set. 96 wheels more. Still being dialed in. =-
The cross over tube will not help much.... so why bother. Some forum members have found that you can stick steel wool in one tip of each muffler and the go is resonance reduced. I run Borla ZR1 style mufflers on my go and it gives resonance a whole new meaning.... but I've found that by stuffing towels/car parts/tools/jumper cables into the storage compartments (under the plastic trays) helps out a lot with the noise.... sort of an insulating cause.
after loging in 2000 miles in my first corvette with flowmasters. I experience what you mean with the resonence "tone" in the cockpit but believe me or not. I dont think its as loud outside the car the exaust is loud but it does not furnish that 1800 rpm emit out the tailpipe. I think its a cockpit thing. I plan on solving this by cranking up my stereo and adding a 600 wat amp.! - haha no seriously im going to sight a place to buy some DYNOMAT insulation and im not takling a cheap o version of it. I be the real dynomat stuff and I intend on plastering it everywhere under every piece of carpet and all around the straighten storage this should get rid of alot of road noise and exaust drone in the cabbin.[ADVERTHERE]Related article:
http://forums.corvetteforum.com/showthread.php?t=1806283
0 Comments:
No comments have been posted yet!
|
