I just want to share some experience of having an aftermarket downpipe which I installed last Saturday.
Before this, I've done some research and some comments I read about having aftermarket downpipe has improved the car performance pretty well. I was sceptical of course. I know our stock downpipe design is not the best but I would not think having it will make a whole world of difference.
When I dyno tuned my car a month ago, my boost capped at 1.2 bar. At that time, we do not know what is the cause, so the tuner told me it could be the stock downpipe issue where else Ah Wah said it's the weak stock actuator. No matter how we crank up the boost, it won't go above 1.2 bar.
A week later, we found out that there's a leaky vacuum pipe. So it's not the downpipe nor weak actuator.
The tuner told me that stock downpipe design is kinda 'flatten' and has a lot of curves and dents. So those whose running bigger turbo with more airflow, will benefit a lot from having an aftermarket downpipe.
My comments: Car car actually felt smoother, more responsive - 'lighter', less turbo lag and of course, more powerful. About more power or not, I plan to send my car to dyno tune again soon. Hoping to see some numbers running aftermarket downpipe + 1.5 bar. Accordingly to Ah Wah, I am hoping to see above 270whp.
So my conclusion: If you're running stock TD04 with boost below 1.3 bar, I think stock downpipe may still be adequate. Any mods like bigger turbo, the more airflow required, the more benefit you get out of having an aftermarket downpipe.
Hope this infomation is helpful.
PS: Downpipe is from HKS for Evo but re-weld to fit Airtrek.
Before this, I've done some research and some comments I read about having aftermarket downpipe has improved the car performance pretty well. I was sceptical of course. I know our stock downpipe design is not the best but I would not think having it will make a whole world of difference.
When I dyno tuned my car a month ago, my boost capped at 1.2 bar. At that time, we do not know what is the cause, so the tuner told me it could be the stock downpipe issue where else Ah Wah said it's the weak stock actuator. No matter how we crank up the boost, it won't go above 1.2 bar.
A week later, we found out that there's a leaky vacuum pipe. So it's not the downpipe nor weak actuator.
The tuner told me that stock downpipe design is kinda 'flatten' and has a lot of curves and dents. So those whose running bigger turbo with more airflow, will benefit a lot from having an aftermarket downpipe.
My comments: Car car actually felt smoother, more responsive - 'lighter', less turbo lag and of course, more powerful. About more power or not, I plan to send my car to dyno tune again soon. Hoping to see some numbers running aftermarket downpipe + 1.5 bar. Accordingly to Ah Wah, I am hoping to see above 270whp.
So my conclusion: If you're running stock TD04 with boost below 1.3 bar, I think stock downpipe may still be adequate. Any mods like bigger turbo, the more airflow required, the more benefit you get out of having an aftermarket downpipe.
Hope this infomation is helpful.
PS: Downpipe is from HKS for Evo but re-weld to fit Airtrek.
