2.75 downpipe 3 inch exhaust
#1
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2.75 downpipe 3 inch exhaust
I have searched and have not found the answer. Either I search bad or this is to stupid to ask.
I have the beginning s1 kit. The dp is 2.75. I am looking to buy an exhuast and cat. Seems like I should go 3 inch. But with the 2.75 dp am I just blowing a few extra bucks for the .25 inches that I can not utalize do to the downpipe size.
I find a lot of posts saying go with the three inch but none that asked about the dp size. Maybe most have three inch dp?
I have the beginning s1 kit. The dp is 2.75. I am looking to buy an exhuast and cat. Seems like I should go 3 inch. But with the 2.75 dp am I just blowing a few extra bucks for the .25 inches that I can not utalize do to the downpipe size.
I find a lot of posts saying go with the three inch but none that asked about the dp size. Maybe most have three inch dp?
#4
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Thinking to go with the MeganaFlow 3 inch cat. $109
then go with the enthuza turbo exhaust. $419.
Seems to be the most reasonable prices I can find. Also seems like the posts i have found people have spoke well of both items. The enthuza cat might be nicer but it is 2x more expensive. Everything for me comes down to budget. I do agree going with the 3 now is the way to go. Little sad by not having a real DP.
then go with the enthuza turbo exhaust. $419.
Seems to be the most reasonable prices I can find. Also seems like the posts i have found people have spoke well of both items. The enthuza cat might be nicer but it is 2x more expensive. Everything for me comes down to budget. I do agree going with the 3 now is the way to go. Little sad by not having a real DP.
#8
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Braineack - That is what i was not undestanding. I was thinking the bottleneck would be the downpipe so there would not be an advantage of going larger after the DP.
I am now understanding that I should not let the limited DP size limit the size of the exhaust past that point.
Oh lordy 4" .. now I have another thing to think about. I do not think I need 4" with the power I plan on doing.
Shuiend - I needed a shop to weld the exhaust together. My assuption was that it would fit. And this is why I make posts because simple things I forget... Like will it actualy fit. I am also going to contact Enthuza to see if they have a more budget set up for a 3" that would work.
I am now understanding that I should not let the limited DP size limit the size of the exhaust past that point.
Oh lordy 4" .. now I have another thing to think about. I do not think I need 4" with the power I plan on doing.
Shuiend - I needed a shop to weld the exhaust together. My assuption was that it would fit. And this is why I make posts because simple things I forget... Like will it actualy fit. I am also going to contact Enthuza to see if they have a more budget set up for a 3" that would work.
#9
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Shuiend - I needed a shop to weld the exhaust together. My assuption was that it would fit. And this is why I make posts because simple things I forget... Like will it actualy fit. I am also going to contact Enthuza to see if they have a more budget set up for a 3" that would work.
#12
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Braineack - Why would I have to take an intro class when you just informed of everything I need to know ;o)
I get stuck in the computer world. The way things bottleneck on a network is completly different. Data will only move as fast as the most restrictive point. It is a learning process and I have enjoyed it thus far.
I do appreciate the help that the forum has provided. And I do try to find things on my own and research before asking. I am going to look up fluid dynamics and see I can find on air flow.
Thanks Again
I get stuck in the computer world. The way things bottleneck on a network is completly different. Data will only move as fast as the most restrictive point. It is a learning process and I have enjoyed it thus far.
I do appreciate the help that the forum has provided. And I do try to find things on my own and research before asking. I am going to look up fluid dynamics and see I can find on air flow.
Thanks Again
#13
Boost Czar
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nutshell:
high pressure to low pressure.
exhaust gasses cool, slow and expand as they travel through the exhaust. A smaller DP encourages higher flow aft turbo, where the large exhaust allows for less restrictons/bottleneck as the exhaust gasses start to fill out and pack onto each other.
high pressure to low pressure.
exhaust gasses cool, slow and expand as they travel through the exhaust. A smaller DP encourages higher flow aft turbo, where the large exhaust allows for less restrictons/bottleneck as the exhaust gasses start to fill out and pack onto each other.
#15
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That gasses certainlly don't contract. Gases expand to fill a container. So with that being said, the more volume you have in your exhaust piping, the more exhaust you'll be able to put into it before having to compress it.
So the idea of a smaller diameter DP tube encourages higher velocity...where the turbo has an easiiery job of expelling large quanities of gasses due the the scavenging effect.
If the exhaust tube isn't increased, then the gasses fill up the tubes, and stack up and create backpressure and the turbo must push against it all in order to continue to expell. This is reduces power output.
A step increase, especially after the wastegate dump, is the best way to promote exhaust flow, velocity, and scavenging to reduce the amount of torque waisted pushing out the exhaust and not pushing down the pistons.
Think about how your IM tapers down into a very smaller runner...this increases promotes the increase of velocity into the combustion chambers, allows all the oxygen molecoles to stack up and pile up in as fast as possible...we are doing the opposite on the other side--promoting them to get the hell out.
So the idea of a smaller diameter DP tube encourages higher velocity...where the turbo has an easiiery job of expelling large quanities of gasses due the the scavenging effect.
If the exhaust tube isn't increased, then the gasses fill up the tubes, and stack up and create backpressure and the turbo must push against it all in order to continue to expell. This is reduces power output.
A step increase, especially after the wastegate dump, is the best way to promote exhaust flow, velocity, and scavenging to reduce the amount of torque waisted pushing out the exhaust and not pushing down the pistons.
Think about how your IM tapers down into a very smaller runner...this increases promotes the increase of velocity into the combustion chambers, allows all the oxygen molecoles to stack up and pile up in as fast as possible...we are doing the opposite on the other side--promoting them to get the hell out.
Last edited by Braineack; 02-02-2012 at 01:54 PM.
#19
I have it the wrong way round 3 inch t25/t28 elbow to 2.75 inch evo downpipe. It is a good fit though
http://i578.photobucket.com/albums/s...3/P1020570.jpg
http://i578.photobucket.com/albums/s...3/P1020570.jpg