Hey, so I bought a mk5 Golf GTTDi last year, done a lot of cosmetic mods now I'm planning some performance ones and need some advice please :)
Decat - Should I cut the cat out myself & weld it up (anyone got a guide) or buy a downpipe and just replace the whole thing? Would there be any extra power gain with buying one?
Remap - Is there anything I should do to the car besides decat & exhaust before getting it mapped?
Air filter - Should I get a K&N one or any other one for a little extra power? Or just stick to the VW ones..
I'm using the car for work & leisure so I don't want it to be too bad on fuel but also fast & fun.
If any of you have a spare 5 mins to give me some advice that'd be great, cheers!
Decat - buy a proper 2.5 / 3 inch pipe . less lag from turbo and remove rear silencers with the equal length pipe for a nice straight through system.. or small in line silencer if you want a bit less noise.
remap - yes of course. and put egr delete pipe on at same time. also fit new fuel filter and run with decent fuel , vpower or bp ultimate
air filter - leave it as stock with new filter .. if you want to go open cone then use an s2000 filter and put a proper heat shield on.
makes no differnce economy vs power to be honest, well tuned it will make the same or better MPG when cruising... best bang for your buck is darkside GTB turbo budget kit with a 1756vk on a cast manifold.
think it's £1800+vat drive in drive out service also includes a free service.
stock 2.0 tdi turbos on the BKD engine usually sh*t themselves. no 140bhp PD engined Mk5 Golfs had DPFs