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Gained 5mph over using WHAT?
What did that replace? 5mph gain is a LOT.
I'm curious what you had prior to Mufflex/Flowmaster merge.
I have a mild 6.0 with just a set of 1-3/4" BBK longtubes and their included Y.
Turbo spec'd cam that it had, showed zero gain between full closed exhaust (Jeg's) and 3" cutout open, mounted in the "I" pipe under passenger side rear seat.
Now with better cam, there's an obvious power difference between the two.
Just trying to figure if I should "start over" exhaust wise?
Isn't the BBK Y-pipe 2.5 inches? I'm sure you'd see a nice gain going to the 4" FM merge
Isn't the BBK Y-pipe 2.5 inches? I'm sure you'd see a nice gain going to the 4" FM merge
Tried to look on BBK website, which sucks. I wasn't even able to look at anything there, but I believe you are right.
I think they are 1.75" primaries to 3" collectors, then from flanges to 2.5" pipes to the "Y", then 3" from there.
I only chose it due to me feeling it was a better "Y" transition (dual 2.5's, to 3"), as opposed to most others, which are dual 3" to single 3"
Are you saying to just adapt a 4" merge to what I have?
Or swap to a 3" Y pipe?
I guess a new 3" Y pipe, merged into a 4", then mated to the rest of my 3" exhaust wouldn't be too bad to figure out.
My entire exhaust, from header gasket to exhaust tips is new, so this kinda sucks...
I know I had to "oval" near the "Y" part to clear my Spohn chassis mount torque arm crossmember.
I can't imagine trying to fit a 4" Y in that spot, but it does look like it's pretty flat (oval), where it would go between the crossmember and floorpan.
I wonder if I could/should cut the collector flanges off, and basically convert them to a slip on style, and simply use a different brand 3" pipe, to 4" merge?
The headers fit great, so I'd hate to also have to remove them and buy everything again...although it wouldn't be the first time...LOL
I forgot about the flanged part of the headers, which really creates, at least looks like, a bad bottleneck.
Here's my thinking, someone please critique, if I'm thinking bass ackwards...
1.) Cut the flanges off of the header collectors, which will open them up to a true 3" slip-on style collector
2.) Use a 3" Speed Engineering, TSP, or whoever's, Y pipe
3.) Mate that to a 3" to 4" Flowmaster merge
4.) 4" transitioned back down to 3", mated to existing I pipe back exhaust
or...
Just frickin' start over...LOL...
.
.
I've always been curious how much of a power difference there would be between the BBK's vs a TSP 1 7/8 and 3" y. I had the bbks on my car a while ago and it made decent power and ran 11.70s cam only..
Gained 5mph over using WHAT?
What did that replace? 5mph gain is a LOT.
I'm curious what you had prior to Mufflex/Flowmaster merge.
I have a mild 6.0 with just a set of 1-3/4" BBK longtubes and their included Y.
Turbo spec'd cam that it had, showed zero gain between full closed exhaust (Jeg's) and 3" cutout open, mounted in the "I" pipe under passenger side rear seat.
Now with better cam, there's an obvious power difference between the two.
Just trying to figure if I should "start over" exhaust wise?
Prior set up was BBK no cutout, flow max 2 baffle muffler stock tailpipes = CRAP.
Last edited by handyandy496; 02-20-2019 at 03:41 PM.
I need to measure what my TSP y's merge is before it drops back down. It has to be around 3.5". My foolish *** had 3" adapted straight to that instead of something bigger when I had the whole y tig'd. If only the 4" merge came in 304 stainless.
I’m debating this mod also....I currently have Kooks headers into their older design Y with 3’ cats. The merge doesn’t look so great on it and it goes into a 3’ Borla cat back....
I can’t decide between going with a new Y or mod it to improve the merge into a 3.5 piece of stainless pipe with a cutout and re use the Borla...or swap to the SE true dual exhaust.
I like the idea of using the electric cut out when I want it loud vs the SE and it always being loud and lack of clearance.
Performance wise I’m sure it wouldn’t be much of a difference with the cut out open for my 400ish RWHP combo vs the TD.
Last edited by WidowrRacing; 02-21-2019 at 08:36 PM.
I’m debating this mod also....I currently have Kooks headers into their older design Y with 3’ cats. The merge doesn’t look so great on it and it goes into a 3’ Borla cat back....
I can’t decide between going with a new Y or mod it to improve the merge into a 3.5 piece of stainless pipe with a cutout and re use the Borla...or swap to the SE true dual exhaust.
I like the idea of using the electric cut out when I want it loud vs the SE and it always being loud and lack of clearance.
Performance wise I’m sure it wouldn’t be much of a difference with the cut out open for my 400ish RWHP combo vs the TD.
I bet it gives a good bump in power. Besides junk mergers, on most y pipes the outlet drops to 2.5 in. ID.
The first y pipe on the first page is mine. I run that into a 4in electric cutout with a stock catback so it's quiet when I want it to be. On my setup it made a noticeable difference especially in the higher rpms with my setup.
Last edited by 98CayenneT/A; 02-21-2019 at 09:37 PM.
I think at my power level the Flowmaster 3.5’ merge will do the job and give me a little more clearance around the tunnel mount etc over the 4’.
I’ve read that a single 3.5’ is good for around the 450-500hp range so putting the cut out before it’s reduced to 3’ should do the trick.
Last edited by WidowrRacing; 02-22-2019 at 09:14 PM.
02-18-2019, 09:40 PM
