Turbo Exhaust...How Important are they?
04-12-2006
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Turbo Exhaust...How Important are they?
Maybe I should have picked a different title for this thread, cuz I know that a turbo exhaust is pretty important. I was more or less wondering how different are they to make such a drastic difference in a turbo set up.
I currenty have Thermal R&D exhaust on my 02 VTEC, I have a Greddy T3/T4 turbine and the rest of the kit is being pieced together, weekly. Intercooler pipes are being done in 2 weeks then I tap the pan and go.
I am pretty convinced that I should upgrade to a turbo exhaust, but I having some difficulties finding one for my car. I was wondering if any of you guys are running a turbo exhaust or not. Maybe you switched in from a "normal" exhaust to a turbo. Was there a big gain or what? I am sure the results of this thread are Buy the damn turbo exhaust, but I just want to know the difference first cuz I am already into this thing for like $3500 between the suspension I just finished (progress sway bars F & R and sport springs, NRG strut tower F&R, Megan control arms, camber kit, Tanabe H frame) and this turbo that keeps adding up daily.
I dont want to cut corners but I am sure you all know that springing for this stuff all at once is tough. So how vital is the exhaust and any other turbo add ons for that matter. With that statement I should tell you what i have for the turbo already: BOV, downpipe, turbine, intercooler, oil lines, boost and A/F gauges, fuel pressure regulator, boost controller, manifold, block gaurd....I think thats all of it.
Sorry I typed so long.....Thanks
I currenty have Thermal R&D exhaust on my 02 VTEC, I have a Greddy T3/T4 turbine and the rest of the kit is being pieced together, weekly. Intercooler pipes are being done in 2 weeks then I tap the pan and go.
I am pretty convinced that I should upgrade to a turbo exhaust, but I having some difficulties finding one for my car. I was wondering if any of you guys are running a turbo exhaust or not. Maybe you switched in from a "normal" exhaust to a turbo. Was there a big gain or what? I am sure the results of this thread are Buy the damn turbo exhaust, but I just want to know the difference first cuz I am already into this thing for like $3500 between the suspension I just finished (progress sway bars F & R and sport springs, NRG strut tower F&R, Megan control arms, camber kit, Tanabe H frame) and this turbo that keeps adding up daily.
I dont want to cut corners but I am sure you all know that springing for this stuff all at once is tough. So how vital is the exhaust and any other turbo add ons for that matter. With that statement I should tell you what i have for the turbo already: BOV, downpipe, turbine, intercooler, oil lines, boost and A/F gauges, fuel pressure regulator, boost controller, manifold, block gaurd....I think thats all of it.
Sorry I typed so long.....Thanks
04-13-2006
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Boost is so good make you wanna slap ya mamma
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Any exhaust system with mandrel bent 2.5" or 3" piping is fine.
Last edited by red_sun; 04-13-2006 at 01:58 AM.
04-13-2006
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As long as it has straight through muffler and resonator you're OK.
Pipe diameter depends on the turbo size and WHP goal.
You said you have t3/t4 - then 2.5" and up preffered.
2.25" is OK too, but you'll be loosing some top end power, but at the same time you'll be gaining low-midrange.
Basicaly It's up to you, as long as you complied with what I said in my 1st sentence.
Make sure you dyno when it is fully done!!!!!
Pipe diameter depends on the turbo size and WHP goal.
You said you have t3/t4 - then 2.5" and up preffered.
2.25" is OK too, but you'll be loosing some top end power, but at the same time you'll be gaining low-midrange.
Basicaly It's up to you, as long as you complied with what I said in my 1st sentence.
Make sure you dyno when it is fully done!!!!!
04-13-2006
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Originally Posted by hondoer27
when I saw turbo exhaust I thought you meant you wanted a turbo for you exhaust
Im an idiot
Im an idiot
Anyway, typical turbo exhausts are 2.5"-4". The average street car making less than 500whp will benefit from 2.5". The turbo exhaust is free flowing with minimal to no restrictions and allows for less back pressure, which turbos hate. Also note that the A/R of the exhaust side of the turbo has a dealing in the back pressure as well. A smaller A/R can only shuffle so much air.
As a matter of fact...here is a post we made on another forum:
Originally Posted by paul_dezod
This article is a great foundational article for those who know little or next none about exhaust systems, however with respect to diameter of the exhaust, I think they failed to mention some crucial points like the role of exhaust A/R on back pressure and exhaust size. Just because 3000 Turbo Civic owners putting down 300whp each decide to run 3" exhaust does not mean it's correct.
Ok. Let's start here.....Exhaust A/R on the turbo is like a light beam that you can focus on how large or how narrow and fine you want the overall beam. The wider you want the beam, the less FOCUSED power in range you will have (like a lower A/R, .48 or .63 compared ro a 1.08 A/R). Be aware of an excessively low A/R because it will cause a jumpy and touchy throttle response that might be hard to control. It will spool quick, but die after a short RPM span. So lower A/Rs are a double edged sword and must be treated with a lot of importance for selection of the sized turbo, with goals and how the car is used.......[taken from Maximum Boost]
Higher A/Rs are focused on top end, maximum power and generally have short lives with respect to power bands. Like say 1500 RPMS of power, great for drag racing, but not practical for street. Perfect example, 1.8L Turbo Civic H/B. Not the most ideal street set-up but a great drag set-up.:
But note, this set-up has a large turbo with a small A/R (to aid spool ups) to put down massive top end. Some people have taken the opposite approach like using a T3/T66 turbo on a 3.0L with a large A/R like 1.08 A/R to help focus the smaller exhaust housing's potential on the higher RPM portions.
Anyway, the lower the A/R, the more back pressure it will choke on in the RPMS thus making less top end power, but better mid-range let's say. That .48 A/R will choke it'self to death in back pressure on the top end because that wheel can not shuffle the air fast enough past it to get into the exhaust system. So several pulses may go by, and in event, clusters of air are given a bit more time to cool requiring more effort to expunge from the system. Add a larger diameter piping, which slows exhaust velocity down, and viola! Bad news.
Turbos create back pressure and hate it as well. As minimal restriction as possible with respect to turbo is the best. However exhaust gas can only move a certain speed and is generally lazy as well. Hence why Mandrel bends are better than Crush Bends in exhaust systems. Crush flow like crap and are very restrictive. Exhaust gases don't want to jump through firing hoops....They just want to get out of there as easy as possible....So Mandrel bends are an attempt to keep the exhaust gas flowing in a staright line as much as possible with still having optimal flow. (No dimished diameters in piping through bends and curves either!) So here Corky Bell has a guide to help deciding some exhaust diameters based upon HP.
I hope this helps too.
Ok. Let's start here.....Exhaust A/R on the turbo is like a light beam that you can focus on how large or how narrow and fine you want the overall beam. The wider you want the beam, the less FOCUSED power in range you will have (like a lower A/R, .48 or .63 compared ro a 1.08 A/R). Be aware of an excessively low A/R because it will cause a jumpy and touchy throttle response that might be hard to control. It will spool quick, but die after a short RPM span. So lower A/Rs are a double edged sword and must be treated with a lot of importance for selection of the sized turbo, with goals and how the car is used.......[taken from Maximum Boost]
Higher A/Rs are focused on top end, maximum power and generally have short lives with respect to power bands. Like say 1500 RPMS of power, great for drag racing, but not practical for street. Perfect example, 1.8L Turbo Civic H/B. Not the most ideal street set-up but a great drag set-up.:
But note, this set-up has a large turbo with a small A/R (to aid spool ups) to put down massive top end. Some people have taken the opposite approach like using a T3/T66 turbo on a 3.0L with a large A/R like 1.08 A/R to help focus the smaller exhaust housing's potential on the higher RPM portions.
Anyway, the lower the A/R, the more back pressure it will choke on in the RPMS thus making less top end power, but better mid-range let's say. That .48 A/R will choke it'self to death in back pressure on the top end because that wheel can not shuffle the air fast enough past it to get into the exhaust system. So several pulses may go by, and in event, clusters of air are given a bit more time to cool requiring more effort to expunge from the system. Add a larger diameter piping, which slows exhaust velocity down, and viola! Bad news.
Turbos create back pressure and hate it as well. As minimal restriction as possible with respect to turbo is the best. However exhaust gas can only move a certain speed and is generally lazy as well. Hence why Mandrel bends are better than Crush Bends in exhaust systems. Crush flow like crap and are very restrictive. Exhaust gases don't want to jump through firing hoops....They just want to get out of there as easy as possible....So Mandrel bends are an attempt to keep the exhaust gas flowing in a staright line as much as possible with still having optimal flow. (No dimished diameters in piping through bends and curves either!) So here Corky Bell has a guide to help deciding some exhaust diameters based upon HP.
I hope this helps too.
04-13-2006
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Rep Power: 0 Okay, so there is really no difference between the exhaust I have on already and a "turbo" exhaust? There has got to be some difference for them to dub it a turbo exhaust.
But I am glad that the exhaust I have now will not hurt my set up. I will definately post dynos when I get it all done thanks guys.
But I am glad that the exhaust I have now will not hurt my set up. I will definately post dynos when I get it all done thanks guys.
04-13-2006
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Originally Posted by DJayG
Okay, so there is really no difference between the exhaust I have on already and a "turbo" exhaust? There has got to be some difference for them to dub it a turbo exhaust.
But I am glad that the exhaust I have now will not hurt my set up. I will definately post dynos when I get it all done thanks guys.
But I am glad that the exhaust I have now will not hurt my set up. I will definately post dynos when I get it all done thanks guys.
04-13-2006
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Rep Power: 237 Not jacking your thread but since all the pros are chiming in , wuts the ideal size piping to run a hybrid swap k24/k20a2 plz?
Btw : OHh theres a thread in this section where you can contact all the turboed guys. So go there and start pming
Btw : OHh theres a thread in this section where you can contact all the turboed guys. So go there and start pming
04-13-2006
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Originally Posted by blackdragon
Not jacking your thread but since all the pros are chiming in , wuts the ideal size piping to run a hybrid swap k24/k20a2 plz?
Btw : OHh theres a thread in this section where you can contact all the turboed guys. So go there and start pming
Btw : OHh theres a thread in this section where you can contact all the turboed guys. So go there and start pming
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