OK so i ust got a boost guage( and fixed my limp mode problem, Huray!) and i've been watching the boost. I've noticed taht as i hit the higher RPMs my boost tends to drop off. Assuming this is normal, is this from the back pressure of the exhaust becoming to great or is it because of a Low A/R of the turbine. I've looked all over google but i can't find any specs on teh turbo. My main reason for asking is that if the drop in Bars is because of the high back presure at high RPMs i could get a new exhaust and eliminate this problem( I know i should get one neways but I'm just trying to figure this out) if it is because of a low A/R i would imagine that the K04 is nearly the same. I'm just trying to figure out what i'm gonna do with my car. So let me know what you think. OR if you have any specs on the K03

 

The K03 is tiny and it runs out of steam high in the rpm range quickly because it's so small.. It was designed so that you couldn't feel the turbo lag or surge.

 

so basically it has a low A/R on the turbine and creates to much back pressure at high RPMs to be efficent. Thats what i thought but i wasnt sure

 

No. The K03 is so small that it simply can't supply enough airflow.

 

oh, does the K04 have the same problem?

 

Not nearly as prevalent with the K04. It's a little bit bigger and has much better flow.

 

basically yes

 

the ko4 still runs out of breath, you still get fall off in upper rpm's, i was not all that impressed.. the ko4 spools realy quick and gives ou a nice jolt and great low tq numbers but it still lacks top end..

 

I loved all the tq when i drove a k04'd99 1.8t, but it does still drop off at higher rpm's.