FMIC and pipe size questions

[golf-sib]

since I am fitting a FMIC I have alot of questions, the pipe work will all get done, but what size piping should I aim for?

Simple reason for asking is that the piping is traveling a bigger length it will increase or create lag in the turbo, so I imagine bigger piping would be worse, due to the greater increase in cubic area?

My plan is to aim for 50mm ID pipping, simply because that is what the turbo size outlet is. However I noticed on the Golf the piping comes out at 50mm, then enlarges to 57mm all the way through, and then jumps in size again at the TB to 60mm. Yet on the Audi A4 1.8T its different as the size is 50mm from the turbo all the way round till you reach the TB.

Whether bigger is better I'll let you guys tell me as reducers can be ordered in easily enough 

[wayne_gtiT]

in my opinion i dont think you will get much lag if you have 3 inch pipes, as the turbo is small and spool's up very quickly, wait for somone with a bit more knowledge on the subject tho

[golf-sib]

Thanks wayne, it's all wierd why the same engine, yet on the a4 they would keep it all 50mm, yet on the golf let the piping have more cubic volume, hopefully someone can shine some light and advice.

[linz]

depends on the intercooler for mine i got 2.5"