Wastegate exhaust size

[Keeper of The Kitten]

@ Audi CQ, that is impressive power with your setup (admittedly an extra 0.5" on the DP compared to my proposed version) ...but don't you just wonder if it might be significantly more with a single, larger and shorter pipe?!!

@ Ross, I'm a country boy - not a problem with neighbouring townfolk where I come from!!!

@ Billman, perhaps a WG dump can be added, not opening up the full exhaust system but just the WG, which otherwise connects to the system further down. IMHO it would be better not to add any side-tappings to the pipe that might induce turbulence?

Some good feedback guys, appreciated!

__MDC__

[Billman]

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[Audi_CQ]

@ Audi CQ, that is impressive power with your setup (admittedly an extra 0.5" on the DP compared to my proposed version) ...but don't you just wonder if it might be significantly more with a single, larger and shorter pipe?!!
__MDC__

Most important area is right after turbo in the DP. Exhaust quickly cools after this and you don't need so large diameter pipes. Because of this I don't think power would be that much higher with a shorter single pipe. Other factors like larger A/R on exhaust side of turbo would get you a higher gain then larger pipes after turbo.

[Keeper of The Kitten]

Agree with you there regarding the gases cooling, that's a fair point.

I think Ø3" DP is about right for me, particularly if the WG remains separate at least until further along the system.

My secondary consideration of the shorter single pipe is to keep the weight down and that remains a goal of mine. I could go to a reduced wall thickness but I don't want to reduce the durability of the pipe, so I fully intend to stick with 16swg.

Right - back to the original question - the stock WG pipe that joins into the stock DP measures about 41mm, which is Ø1-5/8" - it will depend on availability of tube sizes but I searched the forum and it seems that Ø2" is popular.

I was asking earlier in the thread about size relative to the actual WG opening ...or maybe the WG port size in the EM - if the port size in the EM is about the same as the ID of a Ø2" pipe, does that make a Ø2" pipe the ideal size?

__MDC__