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Flowmaster catback question

Old Oct 17, 2010 | 02:22 PM
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Question Flowmaster catback question

Car has longs tubes custom y pipe all 3.5 inch pipe. My question is the how bad does the flowmaster catback flow I have read that they are really restrictive.Anybody have any experience or info

Last edited by Quick99TransAm; Oct 17, 2010 at 02:39 PM.
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Old Oct 17, 2010 | 02:32 PM
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Check my sig for numbers, really didnt loose any.
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Old Oct 17, 2010 | 03:01 PM
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I felt it flowed well enough and went mid 11s with no problem. I liked that the catback, even with longtubes and no cats, kept everything quite enough to keep the cops off my back. If you worried about maximum flow I would suggest a cutout. Once the cutout went on it sounded like a whole different car, but i could hit a switch and shut it up lol
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Old Oct 17, 2010 | 03:25 PM
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I agree with lsjuanmike. I have an electric cutout so I can be loud when I want. I tell ya, the flowmaster with catted y and headers sounds great outside the car with the cutout closed, it doesnt sound loud inside, but outside, it sounds great.
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Old Oct 18, 2010 | 03:21 PM
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Old Oct 19, 2010 | 12:15 PM
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i have never had flowmaster but i always hear how poor they flow...but it really cant be THAT bad. who knows
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Old Oct 19, 2010 | 12:18 PM
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I love the way my Flowmaster sounds (just the muffler) but there's noticeable drone on the freeway and it's hard to talk to people in my backseat. Anyone had comparison with the TSP Rumbler catback? Something cheap and quieter would be nice....
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Old Oct 19, 2010 | 12:44 PM
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I have the flowmaster but no dyno numbers to compare. Dyno'd 378 rwhp on a mustang with my old LM1. Did run a 13.43 this summer with it, then 13.15 without it (High DA, 2.2 60', and first time drag racing). Might be dynoing this saturday. I have LT's, ORY, and a 16" glasspack before the CB. Decent sound but nothing like the magnaflow and similar. Im ditching the flowmaster this winter if you want one.
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Old Oct 19, 2010 | 01:10 PM
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^sick hugger.

...I am running hooker LT's with their matching ORY. I went ahead and removed the portion of the outlet that necks down to 2 3/4 and replaced it with a 3" v-band. Then I ran dynomax 3" intermediate pipes into an 80 series, with hooker dual tips finishing it off.

I enjoy the sound and tone very much. Handles a 12 hour road trip no problem.

I also have hooker headers and another 80 series on my 87.

I've never really suscribed to the "my muffler is better" drama. I love the sound of the aerochamber, and the magnaflow is growing on me too. Wish I had one of each to change as I pleased.

Neither of my camaros feel like its missing a cylinder just because i have a flowmaster.
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Old Oct 19, 2010 | 03:31 PM
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My car in sig has hooker lt's with flowmaster catback. I get alot of compliments on how it sounds. i figure it must not be restricting performance too much since Im running side be side with cars that trap 115 in the 1/4... I have not tracked it yet but on a g-tech I have pulled 12.59 @ 118.4(1200 da), this is with the stock stall, stock cam/heads, and 17" street tires. I have always found the g-tech to be 3-5mph off, so I gues that explains why it runs with cars that trap 115 lol. Point is the flowmaster catback is not nearly as bad as the internet makes it out to be.
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