Personally, I really don't like the way flowmasters sound too much. Especially on 4 cyl engines... I know of one that was installed in a Datsun 510 with a '91 240SX 2.4L DOHC four in it, and i can't stand it. I can't really describe it, I just know that i hate it. It isn't the stupid high pitched "rice" tone, but it just doesn't work for me, it sounds bad IMO. I like the tone that Magnaflow straight through perforated core mufflers give. And on a pushrod b20 I'm sure they'd sound awesome. Here's Magnaflow sounds that are using straight through perforated core mufflers, and here's my car on the dyno, with a full Skandix 2" mandrel bent system with perforated core straight through mufflers that I bought off of ebay for a measly $185 or so.

That's how I fell about it, and some sound clips to let you listen too.

And here's flowmaster's sounds page. The ones on there, of the four cylinder cars, don't sound too bad, but I know that some of them do. The flowmaster sound isn't to my taste, that's all. I guess it isn't really a bad sound or anything. And then i have a built in bias because most of their mufflers aren't straight through... =D
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Kyle - '68 Volvo 142 w/71 b20b and m40...