Power potential from a 2.5" y-pipe?
Originally Posted by ELMiN8oR
LS1 stock block is a 346. so it doesn't matter whether it's a 3" or a 2.5", they are all the same. thats what he meant 
thanks man. I probly didnt ask the question with enough detail. I guess what i'm asking is when I get more mods on my car like cam,heads,intake will the 2.5" y-pipe be holding me back from making more power because its not big enough? Is there some chart that explains and shows how much certain pipe diameters are good for? meaning at what point is it time to change to a bigger size?
Trending Topics
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
Originally Posted by senicalj4579
Is there some chart that explains and shows how much certain pipe diameters are good for?
https://ls1tech.com/forums/showpost....5&postcount=14
ypipe is going to start holding you back pretty soon, not based on the size of the y, but based on what it necks down to.
In other words, if your ypipe is 2.5" x 2.5" --> 3" collector, then you are going to be limited to the collector size of 3", for total efficiency of 369 hp.
All the more reason to save your money for 2.5" true duals. They are good for over 500 hp. Plus you will get more tq from true duals than you would any ypipe. And the sound is fantastic.
TECH Apprentice
Joined: Oct 2005
Posts: 375
Likes: 0
From: Kuwait
Originally Posted by lsx
All the more reason to save your money for 2.5" true duals. They are good for over 500 hp. Plus you will get more tq from true duals than you would any ypipe. And the sound is fantastic.
Originally Posted by lsx24
Yes, this post here:
https://ls1tech.com/forums/showpost....5&postcount=14
ypipe is going to start holding you back pretty soon, not based on the size of the y, but based on what it necks down to.
In other words, if your ypipe is 2.5" x 2.5" --> 3" collector, then you are going to be limited to the collector size of 3", for total efficiency of 369 hp.
All the more reason to save your money for 2.5" true duals. They are good for over 500 hp. Plus you will get more tq from true duals than you would any ypipe. And the sound is fantastic.
https://ls1tech.com/forums/showpost....5&postcount=14
ypipe is going to start holding you back pretty soon, not based on the size of the y, but based on what it necks down to.
In other words, if your ypipe is 2.5" x 2.5" --> 3" collector, then you are going to be limited to the collector size of 3", for total efficiency of 369 hp.
All the more reason to save your money for 2.5" true duals. They are good for over 500 hp. Plus you will get more tq from true duals than you would any ypipe. And the sound is fantastic.
perfect thanks man. the only thing that sucks is i just bought my exhause system back in march. and its not a cheap system. looks like i may be doing it all over again will td this time
thanks though, this is big help 
Originally Posted by lsx24
Yes, this post here:
https://ls1tech.com/forums/showpost....5&postcount=14
ypipe is going to start holding you back pretty soon, not based on the size of the y, but based on what it necks down to.
In other words, if your ypipe is 2.5" x 2.5" --> 3" collector, then you are going to be limited to the collector size of 3", for total efficiency of 369 hp.
All the more reason to save your money for 2.5" true duals. They are good for over 500 hp. Plus you will get more tq from true duals than you would any ypipe. And the sound is fantastic.
https://ls1tech.com/forums/showpost....5&postcount=14
ypipe is going to start holding you back pretty soon, not based on the size of the y, but based on what it necks down to.
In other words, if your ypipe is 2.5" x 2.5" --> 3" collector, then you are going to be limited to the collector size of 3", for total efficiency of 369 hp.
All the more reason to save your money for 2.5" true duals. They are good for over 500 hp. Plus you will get more tq from true duals than you would any ypipe. And the sound is fantastic.
ok wait, so you mean its not the size of my y-pipe its the size of my I pipe? i have 3"collectors and either a 2.5 or 2.75 y-pipe going into a 3" I pipe for he catback. The system is starting to hold me back at the 3" 369 hp mark? I'm not doubting this but why are there so many guys making like 500hp on 3"? These figures must be when the size of the pipe starts to limit your gains?
Originally Posted by senicalj4579
ok wait, so you mean its not the size of my y-pipe its the size of my I pipe? i have 3"collectors and either a 2.5 or 2.75 y-pipe going into a 3" I pipe for he catback. The system is starting to hold me back at the 3" 369 hp mark? I'm not doubting this but why are there so many guys making like 500hp on 3"? These figures must be when the size of the pipe starts to limit your gains?
In other words, this is the point where the exhaust starts to become a restriction in the system. That doesn't mean you can't make more power with it, as there are many people who are, but they are leaving some power on the table.
Originally Posted by senicalj4579
also, lets say i'm making 500hp with my current system....how much power do you think i'm not being able to use as if i had 2.5" duels?
Originally Posted by lsx24
You are running withing 100% efficiency of 2.5" true duals, with 500 hp, so they are not holding you back at all.
ok, so if its not the size of the y-pipe and its the size of the I pipe then what if I go to a 4" catback off of the 2.5" y-pipe? I read somewhere your supossed to stay a consistant size throughout the system but who knows?
If you go 4" ipipe, after the 2.5" ypipe, you'll have a pretty evenly matched setup.
Dual 2.5" flow almost the same as a single 4", right around 500 hp. 4" will flow a little more than dual 2.5", more like 650 hp, according to the above link.
Dual 2.5" flow almost the same as a single 4", right around 500 hp. 4" will flow a little more than dual 2.5", more like 650 hp, according to the above link.