What turbo do I have?
 

I've been reading mixed things.

I have an 03 1.8t turbo AMB engine quattro

do i have a k03s or a k03?

K03s, the regular K03 was last used in the 2000 ATW block.

ok thanks. so i'm guessing upgrading to a k04 wont be a very big gain then.... depressing

Almost none.

Just to put some actual numbers out there, APR's website shows 235HP for the stock turbo with their Stage 1+ ECU & injectors upgrade, and their K04 package is 247HP (both numbers on 93 octane, 91 is slightly less). Pretty minor gain for the extra money (more than $1000 more); probably not worth it unless your stock turbo has failed and you need to replace it anyway, in which case a K04 is only a little bit more money.

I'd be willing to bet they even push about the same maximum boost, but the K04 probably just doesn't run out of breath as much at the high end of the RPM range, thus the extra few HP.

Come on guys, it was a trick question. There is no such thing as a longitude K03s. lol

The old K03 was on the AEB cars. The 2000 got an updated K03 and then the 2001+ got another updated K03. None of them ended up with a K03 Sport which is only found on the Transverse 1.8t's.

If there was a difference in the K03's used on the A4 then the 2001+ cars would make way more power then the pre 2001's once they were all running the same boost level. But the fact is that they dont, they end up making the same power. Maybe this is why my stock K03 on my 2000 ATW was able to produce about 250chp. lol


The problem is way too many people on the A4 forums have been throwing around the name "K03s" to describe the K03 that came stock on the 2001+ cars. They started doing this because they figured their turbo had to be better since their cars made 20hp more stock, but yet that 20hp gain was made by Audi just increasing the stock boost level.

If all the difference is just tuning, why are the numbers different for chips between the engines? Did i miss something here, im confused. Did the companies chip it deliberately that way because of the engine design or something?

It comes down to boost pressure. The older tunes for the earlier A4's were only pushing under 1 bar, then pushed to 1 bar and then around 1.1 bar. For the 2001+ cars tuners started pushing the K03 harder at 1.3-1.45 bar. This is why they show higher hp for those tunes. Do the same on the 058's and you end up making the same power too.

Odd thing is long time ago some of the tuners were offering .8 bar tunes. That is about the same boost the 2001 comes with stock.

Ok. All the same though, the K03 still isn't much of a difference from a K04 to justify the price to power ratio, the OP would still be better off upgrading to at least an eliminator, i think we can all agree on that.

Correct. The K04 just moves the power band slightly up in the rpms with not all that much gains in hp/tq, unless it is really pushed hard. Just better off going to a Frankenturbo or Elim kit.