3 inch piping.
05-25-2008, 11:18 PM
#1
tehLEGOman
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3 inch piping.
...On tuesday i'm going to try a custom 3 inch exhaust, single outlet.
I had always wanted to and on friday the opportunity came to the surface when the exhaust components decided to have a little negotiation with a manhole on my way to Wrightsville beach. In the small town of Wadesboro, the pavement was not complete, and there was a manhole sitting there waiting for me. It wasn't even that tall, maybe 2 or 3 inches. The school bus beside me at the time prevented me from merging lanes, so i decided to charge the manhole. The bumper cleared it, as usual, but this time the exhaust system decided otherwise. An intense BANG, and a loud exhaust note was the result. I was too scared!! haha. Thought maybe the oil pan was done for. Checked the gauges and nothing changed, so i pulled into a motel parking lot. Looked underneath and to my surprise the entire system from the j-pipe back was missing!! hehehe. I started laughing. Went around to the rear and the passenger side of the bumper had come out a little bit. Luckily the varis pieces were still intact. So off i go jogging back down the road to see where the exhaust system is sitting. I'm almost to the spot and there it is,...buddy in a buick or some shit is putting it in his trunk!!! hahahaha. I go up to him, said hello, told him what happened, looked at the exhaust, and say, dude..you can have it. It was all mangled to the death. So back down the sidewalk i go to the TL....laughing during the entire walk. For some reason i thought it was comical.
So i pull the rear passenger wheel off so i could put the bumper back in place. I made the decision that it's safe to continue the trip to the beach, despite not having any piping. So i start the engine, not knowing if the lack of back pressure was going to be an issue. To my surprise, it started fine and ran with ease. Gas mileage went up which was awesome. The engine sounds like a mean pontiac. It also sounds like the Spoon Honda Legend that i've heard in a video. So the current setup is: Primary eshift procats, and 50% j-pipe, then nothing. I think the ATLP j-pipe is where it broke. I can't remember exactly which section is still intact.
My brother has a muffler he got off ebay that i'm going to use. It looks titanium and has a turn down, with a 3 inch diameter inlet. I probably won't use a resonator, so it should sound pretty raw.
Suggestions, input, flames, laughs?!?!...
I had always wanted to and on friday the opportunity came to the surface when the exhaust components decided to have a little negotiation with a manhole on my way to Wrightsville beach. In the small town of Wadesboro, the pavement was not complete, and there was a manhole sitting there waiting for me. It wasn't even that tall, maybe 2 or 3 inches. The school bus beside me at the time prevented me from merging lanes, so i decided to charge the manhole. The bumper cleared it, as usual, but this time the exhaust system decided otherwise. An intense BANG, and a loud exhaust note was the result. I was too scared!! haha. Thought maybe the oil pan was done for. Checked the gauges and nothing changed, so i pulled into a motel parking lot. Looked underneath and to my surprise the entire system from the j-pipe back was missing!! hehehe. I started laughing. Went around to the rear and the passenger side of the bumper had come out a little bit. Luckily the varis pieces were still intact. So off i go jogging back down the road to see where the exhaust system is sitting. I'm almost to the spot and there it is,...buddy in a buick or some shit is putting it in his trunk!!! hahahaha. I go up to him, said hello, told him what happened, looked at the exhaust, and say, dude..you can have it. It was all mangled to the death. So back down the sidewalk i go to the TL....laughing during the entire walk. For some reason i thought it was comical.
So i pull the rear passenger wheel off so i could put the bumper back in place. I made the decision that it's safe to continue the trip to the beach, despite not having any piping. So i start the engine, not knowing if the lack of back pressure was going to be an issue. To my surprise, it started fine and ran with ease. Gas mileage went up which was awesome. The engine sounds like a mean pontiac. It also sounds like the Spoon Honda Legend that i've heard in a video. So the current setup is: Primary eshift procats, and 50% j-pipe, then nothing. I think the ATLP j-pipe is where it broke. I can't remember exactly which section is still intact.
My brother has a muffler he got off ebay that i'm going to use. It looks titanium and has a turn down, with a 3 inch diameter inlet. I probably won't use a resonator, so it should sound pretty raw.
Suggestions, input, flames, laughs?!?!...
05-25-2008, 11:55 PM
#3
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since it broke off at the J pipe, maybe a true dual exhaust?
05-26-2008, 12:04 AM
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let me know if your jpipe got fucked.. cuz I will sell you my atlp jpipe... $350 shipped 
pretty sure it was the jpipe because there isn't much ground clearance
also i have a stock jpipe aswell on the black market...for mad cheap eheheheh
aside from that... 3" tubing should serve you well... have the shop who does it for you raise the exhaust a little....
pretty sure it was the jpipe because there isn't much ground clearance
also i have a stock jpipe aswell on the black market...for mad cheap eheheheh
aside from that... 3" tubing should serve you well... have the shop who does it for you raise the exhaust a little....
05-26-2008, 12:28 AM
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Hey there. Sounds like a fun project, and I wish you the best of results.
I'm no expert by far here, but reading about the quasi-science of exhaust systems, it seems it's possible to oversize the 'plumbing'. The intent of optimizing a system is to minimize backpressure while maintaining tolerable sound levels, and in the extreme (i.e., a total absence of a system), avoiding burning exhaust valves. To achieve this end, one seeks to maximize exhaust velocity, which in turn assures the hottest gas flow; the hotter the gas, the less dense it is, and hence, the less force (i.e., backpressure) required to expel it.
On the surface it might seem that if going from a stock 2.25" dia. to 2.5" dia. is good, then going to 3.0 " is better still. However, this might not prove to be true. Oversizing the exhaust system means the volume increases...going from a stock 2.25" dia to a 3.0 dia = approx. a 24% increase in total gas volume...every exhaust stroke has to push 24% more gas out the muffler(s). At some point, this increase substantially reduces the velocity which equates to a more rapid cooling / loss of heat content of the gas. This makes it more dense, increasing the backpressure.
Your actual results will of course tell if you've crossed that point; You'd need to do b/4/after dynos to verify.
I'm no expert by far here, but reading about the quasi-science of exhaust systems, it seems it's possible to oversize the 'plumbing'. The intent of optimizing a system is to minimize backpressure while maintaining tolerable sound levels, and in the extreme (i.e., a total absence of a system), avoiding burning exhaust valves. To achieve this end, one seeks to maximize exhaust velocity, which in turn assures the hottest gas flow; the hotter the gas, the less dense it is, and hence, the less force (i.e., backpressure) required to expel it.
On the surface it might seem that if going from a stock 2.25" dia. to 2.5" dia. is good, then going to 3.0 " is better still. However, this might not prove to be true. Oversizing the exhaust system means the volume increases...going from a stock 2.25" dia to a 3.0 dia = approx. a 24% increase in total gas volume...every exhaust stroke has to push 24% more gas out the muffler(s). At some point, this increase substantially reduces the velocity which equates to a more rapid cooling / loss of heat content of the gas. This makes it more dense, increasing the backpressure.
Your actual results will of course tell if you've crossed that point; You'd need to do b/4/after dynos to verify.
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05-26-2008, 12:37 AM
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Originally Posted by Snookynibbles
Hey there. Sounds like a fun project, and I wish you the best of results.
I'm no expert by far here, but reading about the quasi-science of exhaust systems, it seems it's possible to oversize the 'plumbing'. The intent of optimizing a system is to minimize backpressure while maintaining tolerable sound levels, and in the extreme (i.e., a total absence of a system), avoiding burning exhaust valves. To achieve this end, one seeks to maximize exhaust velocity, which in turn assures the hottest gas flow; the hotter the gas, the less dense it is, and hence, the less force (i.e., backpressure) required to expel it.
On the surface it might seem that if going from a stock 2.25" dia. to 2.5" dia. is good, then going to 3.0 " is better still. However, this might not prove to be true. Oversizing the exhaust system means the volume increases...going from a stock 2.25" dia to a 3.0 dia = approx. a 24% increase in total gas volume...every exhaust stroke has to push 24% more gas out the muffler(s). At some point, this increase substantially reduces the velocity which equates to a more rapid cooling / loss of heat content of the gas. This makes it more dense, increasing the backpressure.
Your actual results will of course tell if you've crossed that point; You'd need to do b/4/after dynos to verify.
I'm no expert by far here, but reading about the quasi-science of exhaust systems, it seems it's possible to oversize the 'plumbing'. The intent of optimizing a system is to minimize backpressure while maintaining tolerable sound levels, and in the extreme (i.e., a total absence of a system), avoiding burning exhaust valves. To achieve this end, one seeks to maximize exhaust velocity, which in turn assures the hottest gas flow; the hotter the gas, the less dense it is, and hence, the less force (i.e., backpressure) required to expel it.
On the surface it might seem that if going from a stock 2.25" dia. to 2.5" dia. is good, then going to 3.0 " is better still. However, this might not prove to be true. Oversizing the exhaust system means the volume increases...going from a stock 2.25" dia to a 3.0 dia = approx. a 24% increase in total gas volume...every exhaust stroke has to push 24% more gas out the muffler(s). At some point, this increase substantially reduces the velocity which equates to a more rapid cooling / loss of heat content of the gas. This makes it more dense, increasing the backpressure.
Your actual results will of course tell if you've crossed that point; You'd need to do b/4/after dynos to verify.
OMP Prelude has posted the quickest 1/4 mile time being 13.1 at 105mph. He is running 3 inch piping, so this would be the reason why I am deciding to add another .5 inches.
Hopefully it'll work out.
05-26-2008, 12:39 AM
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Originally Posted by stillhere153
let me know if your jpipe got fucked.. cuz I will sell you my atlp jpipe... $350 shipped
pretty sure it was the jpipe because there isn't much ground clearance
also i have a stock jpipe aswell on the black market...for mad cheap eheheheh
aside from that... 3" tubing should serve you well... have the shop who does it for you raise the exhaust a little....
pretty sure it was the jpipe because there isn't much ground clearance
also i have a stock jpipe aswell on the black market...for mad cheap eheheheh
aside from that... 3" tubing should serve you well... have the shop who does it for you raise the exhaust a little....
05-26-2008, 12:41 AM
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Originally Posted by anx1300c
You started laughing?
Please PM me what medication you're on. I want a prescription for it.
Please PM me what medication you're on. I want a prescription for it.
05-26-2008, 12:43 AM
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Originally Posted by ballinfizzle89
You should be good with 3" being F/I.
Damn..you let some random guy cop your HKS muffler?! hahah
Damn..you let some random guy cop your HKS muffler?! hahah
05-26-2008, 02:30 AM
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I had a custom 3" exhaust made for the TL along with a custom 3" J-pipe but i didn't really like the low end. I then switched to the greddy exhaust with stock J-pipe and the daily driving low end was much better. I have a custom 2.5" J-pipe made which is very similar to the atlp J-pipe that i am going to try out. Hopefully that will help the low-mid end a bit.
Let me know how your setup turns out!
Let me know how your setup turns out!
05-26-2008, 06:26 AM
#15
Quiet, Rika Neenja!
Why has no one asked for a sound clip of the current setup? I wanna know what that thing sounds like with nothing behind the J pipe! 
Post a sound clip good sir, and of course another when you're at all 3"!
Post a sound clip good sir, and of course another when you're at all 3"!
05-26-2008, 08:24 AM
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Awesome story. I can see you laughing over this, too...any excuse to mod the car, and this situation completely necessitates it. The best part was some bumpking pocketing the exhaust. Looking forward to seeing the new setup.
05-26-2008, 02:38 PM
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Originally Posted by stillhere153
ur math is so off 
3.0 tubing area of 7.06
7.06/3.97 is 1.77 or a 77% increase.
Granted I havent done any calculating for quite a few years so you might be right
05-26-2008, 06:19 PM
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Originally Posted by VanPelt
2.25 tubing area of 3.97
3.0 tubing area of 7.06
7.06/3.97 is 1.77 or a 77% increase.
Granted I havent done any calculating for quite a few years so you might be right
3.0 tubing area of 7.06
7.06/3.97 is 1.77 or a 77% increase.
Granted I havent done any calculating for quite a few years so you might be right
*PWNED*
05-26-2008, 11:47 PM
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Originally Posted by Laxplaya11385
Van Pelt, you're right
*PWNED*
*PWNED*
05-27-2008, 06:25 AM
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Originally Posted by stillhere153
nope, I didn't know which calculations he had made, i figured he was going merely by percentage which would honestly be a 25% increase... but he's correct via area
The 77% is also the same for volume.If its 25% show me
05-27-2008, 08:19 AM
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Originally Posted by stillhere153
nope, I didn't know which calculations he had made, i figured he was going merely by percentage which would honestly be a 25% increase... but he's correct via area
Originally Posted by VanPelt
2.25 " to 3" is a 77% increase in area
05-27-2008, 10:27 AM
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Originally Posted by VanPelt
^ Fine for F/I , for n/a it would def drone
05-27-2008, 02:11 PM
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Originally Posted by csmeance
since it broke off at the J pipe, maybe a true dual exhaust?
A true dual exhaust be the route that i take after looking at the damage on the lift.
05-27-2008, 02:18 PM
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Update:
So i'm back from meineke. Mildy pissed at the moment because i'm having to brainstorm about which route to take. Need some help !...
Options:
1) Have a dual exhaust made with smaller piping, maybe 1.75 inch piping
2) Cat deletes from Richie, then oem j-pipe, then 3 inch all the way back
3) I dont know
After looking underneath to see the damage, basically the ATLP j-pipe is missing. The rear eshift cat was pulled back maybe 1/2 inch so putting the oem j-pipe on was a no go. He said he was going to have to heat it up to bend it back and didn't want to catch anything on fire.
Options:
1) Have a dual exhaust made with smaller piping, maybe 1.75 inch piping
2) Cat deletes from Richie, then oem j-pipe, then 3 inch all the way back
3) I dont know
After looking underneath to see the damage, basically the ATLP j-pipe is missing. The rear eshift cat was pulled back maybe 1/2 inch so putting the oem j-pipe on was a no go. He said he was going to have to heat it up to bend it back and didn't want to catch anything on fire.
05-27-2008, 05:54 PM
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I goofed up in my original post…the (approx.) 24% increase posted was actually the % increase of cross-sectional area of a TL stock 2.25” dia pipe upsizing to the 2.5” dia found on certain aftermarket, catback systems. The 77% increase is correct for representing the increase from stock to a 3” diameter. And since the length of the system doesn’t change, the % increase in area also reflects the same % increase for volume.
Just non-authoritative chit-chat by me, but a 77% increase in volume seems tremendous. This would greatly reduce the velocity of flow. Again, the longer the gas remains in the system, the more it cools & the denser/heavier it gets. Plus, the greater surface area of the larger pipe also promotes even more cooling. So the pistons have to work to scavenge not just 77% more gas volume, but 77% more of a denser, heavier gas than from a stock setup…this seems counterproductive...more backpressure for our relatively small displacement motor.
One might safely assume that Honda engineers work to arrive at optimization for economy & power; compromises are made, such as adding resonators/muffler constriction for achieving a sedate & tolerable ride. However, I’d imagine the 2.25” dia stock plumbing is near optimization, except where substantial power gains are involved. And considering how the J series engines won’t tolerate radical external power mods (ie, lots of boost) w/o an internal rebuild, it makes sense that the performance exhaust pro’s (folks like Greddy, Comptech, etc.), made a wise decision to a modest upsizing with a 2.5” dia pipe. But 3”? IMO, there’s a good chance one will actually see less gains going to 3” compared against a 2.5” dia. system. Again, a b/4 – after dyno would be needed to verify.
Also, another way to look at this is to consider how ‘relatively’ little performance is gained over stock from performance exhaust systems for our motors. What gains are seen come mostly from eliminating resonators, mid-mufflers, & from restrictive mufflers…plus the cats. The restrictions come from these choke points, not from the main pipes. Of course, if I’m wrong, with wife’s permission, I’ll jump onto a 3” GB (Not!, hehe).
Just non-authoritative chit-chat by me, but a 77% increase in volume seems tremendous. This would greatly reduce the velocity of flow. Again, the longer the gas remains in the system, the more it cools & the denser/heavier it gets. Plus, the greater surface area of the larger pipe also promotes even more cooling. So the pistons have to work to scavenge not just 77% more gas volume, but 77% more of a denser, heavier gas than from a stock setup…this seems counterproductive...more backpressure for our relatively small displacement motor.
One might safely assume that Honda engineers work to arrive at optimization for economy & power; compromises are made, such as adding resonators/muffler constriction for achieving a sedate & tolerable ride. However, I’d imagine the 2.25” dia stock plumbing is near optimization, except where substantial power gains are involved. And considering how the J series engines won’t tolerate radical external power mods (ie, lots of boost) w/o an internal rebuild, it makes sense that the performance exhaust pro’s (folks like Greddy, Comptech, etc.), made a wise decision to a modest upsizing with a 2.5” dia pipe. But 3”? IMO, there’s a good chance one will actually see less gains going to 3” compared against a 2.5” dia. system. Again, a b/4 – after dyno would be needed to verify.
Also, another way to look at this is to consider how ‘relatively’ little performance is gained over stock from performance exhaust systems for our motors. What gains are seen come mostly from eliminating resonators, mid-mufflers, & from restrictive mufflers…plus the cats. The restrictions come from these choke points, not from the main pipes. Of course, if I’m wrong, with wife’s permission, I’ll jump onto a 3” GB (Not!, hehe).