Very smooth and mellow but still very loud.... 
3" to 4" Flowmaster Merge
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From: Middletown, DE
3" to 4" Flowmaster Merge I've used the search function, but did not get any definite answers. If there is another thread covering this, feel free to direct me towards it.
Does the 3" to 4" merge actually improve the tone of your F-body? I'm running Kooks headers into a Kooks ORY, which I am assuming is a pretty shitty merge by Kooks since their Y pipes are so cheap compared to headers.
Anyway, getting ready to slap this on Friday.. anyone have experiences/feedback/power gains?
Does the 3" to 4" merge actually improve the tone of your F-body? I'm running Kooks headers into a Kooks ORY, which I am assuming is a pretty shitty merge by Kooks since their Y pipes are so cheap compared to headers.
Anyway, getting ready to slap this on Friday.. anyone have experiences/feedback/power gains?
https://ls1tech.com/forums/generatio...ut-dumped.html
I am still running a single 4" dumped, and a 3" catback when needing to be quiet, with the cutout open, I picked up 14 rwhp, and 15 rwtq on a 98* day. Worked nicely.
If you are just doing a merge with a reducer into a catback with no cutout, I am just guessing, but maybe 2-3 hp? Someone may have tested it this way. The power in your sit, I think you would make a bit more than I made with a cutout.
01SSREDA4 will probly post up about the merge, I know he was running one.
Personally it will not improve the tone if you are dumping it without a muffler. I squeezed a dynomax bullet before the cutout and it eliminated the rasp and made the exhaust really deep and personally one of the best sounding exhausts I have heard around my area.
I am still running a single 4" dumped, and a 3" catback when needing to be quiet, with the cutout open, I picked up 14 rwhp, and 15 rwtq on a 98* day. Worked nicely.
If you are just doing a merge with a reducer into a catback with no cutout, I am just guessing, but maybe 2-3 hp? Someone may have tested it this way. The power in your sit, I think you would make a bit more than I made with a cutout.
01SSREDA4 will probly post up about the merge, I know he was running one.
Personally it will not improve the tone if you are dumping it without a muffler. I squeezed a dynomax bullet before the cutout and it eliminated the rasp and made the exhaust really deep and personally one of the best sounding exhausts I have heard around my area.
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From: Middletown, DE
Thanks for the reply and link to related thread. I am not dumping the exhaust, it's actually completely fabbed up.
Kooks LT Headers > Kooks ORY > ((Flowmaster Merge)) > Short classic chambered Powerstick > (over the axle) > Borla catback with Dynomax in place of borla (one side is straight piped, the other side has a dynomax bullet)
Car sounds awesome now, just have some rasp around 2300 RPMS. I also have a 2.5" pipe in the i pipe which I could guess is robbing some power.
I used to have a DMH cutout under there, but all I had were problems with it so I ditched it altogether. My ears also don't ring anymore after driving around and my neighbors don't hate me as much
Recent idle video is in my sig. Does the FM only really show difference in cruising speed?
Kooks LT Headers > Kooks ORY > ((Flowmaster Merge)) > Short classic chambered Powerstick > (over the axle) > Borla catback with Dynomax in place of borla (one side is straight piped, the other side has a dynomax bullet)
Car sounds awesome now, just have some rasp around 2300 RPMS. I also have a 2.5" pipe in the i pipe which I could guess is robbing some power.
I used to have a DMH cutout under there, but all I had were problems with it so I ditched it altogether. My ears also don't ring anymore after driving around and my neighbors don't hate me as much
Recent idle video is in my sig. Does the FM only really show difference in cruising speed?
My roommate had some crap 2.5" into 3" y pipe on his car and switched to 3" pipe into the merge you posted and then necked it down to a 3" bullet and it sounds a million times better. No rasp and not real loud, just good clean deep and throaty tone.
Car got a new cam at the same time so can't really say on power...it runs better now but that's about all we know.
Car got a new cam at the same time so can't really say on power...it runs better now but that's about all we know.
I had a tsp y pipe that ran into a gmmg car back. Switched to a 4in merge into a 4in mufflex system and it eliminated all of the rasp that I had with the previous set up. There was a nice little SOP difference as well. Mine isn't quite an apples to apples comparison since I swapped cat backs as well but I think you will be very happy with the 4in merge
He didn't have room for a 4" race muffler, realized that once it came in from Jegs. Sent it back for the 3" which fit a lot better. Did a 45* out dump and it sounds great but isn't too loud and it's that good clean rumble sound. Gets pretty loud under WOT though.
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From: Iowa?
I was running a Pacesetter Y into a 3.5" Mufflex cat-back. It was raspy to say the least; nasty sounding below 3krpm.
I scabbed in a Flowmaster 3.5" merge and it made a huge difference in the exhaust note. There's almost zero rasp now and it felt like there was a small SOP gain, which isn't surprising if you've ever seen a Pacesetter Y merge...
I scabbed in a Flowmaster 3.5" merge and it made a huge difference in the exhaust note. There's almost zero rasp now and it felt like there was a small SOP gain, which isn't surprising if you've ever seen a Pacesetter Y merge...
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From: Middletown, DE
I've seen this before. Awesome setup man. How was the drone under the car? Was it unbearably loud?
I currently have a dynomax but it is further back. Not sure how inspection in Delaware would feel about a dumped exhaust.
Here's how mine currently looks. I call it a Frankenstein exhaust when people ask me what my setup is lol.
I currently have a dynomax but it is further back. Not sure how inspection in Delaware would feel about a dumped exhaust.
Here's how mine currently looks. I call it a Frankenstein exhaust when people ask me what my setup is lol.
The drone was exactly the same as dumped duals like the tsp's. I had duals and ditched them for this. It was lighter, sounded exactly the same, and felt like it performed better. It doesnt have the bottleneck that the x merge on duals has. This flowmaster merge is big and absolutely the smoothest way of merging two pipes. The next one of these I built I angled the turndown out 45* and it made a WORLD of difference inside the car. Very tolerable at that point.
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Turbo306Fox, you can fit it with a little massaging of the floor and the bullet. Check out the link that I posted in the beginning of the thread (reply 13) If you work it, you can also fit a cutout on the end if you want
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Check out post #13 in this thread. Do you think I can get a cutout on the end right by the axle? Wondering how it will sound behind the classic chambered powerstick.
I don't think that you can. If you see my pics, everything was cut to the absolute max. I started at the merge and cut to the limit all the way to the end besides flattening one side of the muffler and some floor pan.
That powerstick is long
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From: Middletown, DE
I think you are right. Oh well. I love the way it sounds now. I had a cutout in the I pipe before this setup and it would make my ears ring. Wondering how much power I'm robbing myself of now