I can't really compare them directly, since I went from standard APR (no injectors) to GIAC with injectors.

But here goes anyway.

APR came on stronger initially, so it felt somewhat more aggressive, but tapered offer in the higher RPM range. It also had a dead spot (in my car anyway) in 1st. Basically you'd need to slightly over rev the engine to get going smoothly, if you didnt it kinda jumped and jerked until it you were fully moving ~5 MPH or so.

The GIAC FX programming is insanely smooth, almost to the point it feels like a non-turbo V6, much like my wifes R32. With the programming and injectors, my lil K03 can hold 20PSI right up to 6500+ RPMs. This may be a result of the extra fuel from the injectors, but the APR flash would spike at 18 or so (depending on boost controller settings) and drop off to ~12 shortly after 4500rpm.

There is obviously more HP and TQ in the FX programming due to the added fuel, but it's a mush smoother ride. if you gun it, you still get thrown back in the seat and stay there until you let off the gas but it's a much smoother, more controlled feeling. It almost feels like the there is more control over the cars performance with GIAC.

 

Good review, glad to hear you like it! Sounds like a good upgrade for you.

 

haven driven both many times giac is top of all your things you listed except top end, they give up a little up to to give you more where you really need it

 

[sm=insomnia.gif] Is 20 psi at redline on a K03 really a good thing? Don't get me wrong, I love my GIAC K04 Hammer File. You are absolutely right about the smoothness and power. It used to take "effort" to hit 80 mph; now I'm at 100 before I realize it.

But, back to the issue of 20 psi at redline. I know you have the fueling to handle it, but I don't know if it's healthy for the turbo or if you are getting that much more power out of it. I found on my GTI that it ran best at 18-19 psi.

 

Nice... GIAC is the **** for sure. Especially in the lower rpms where its most used/useful in everyday city driving. APR's power was too spread out for me over the rpm's.

 

Meh, not really worried about the turbo at the point. The car has ~20k miles on it and the turbo will be out within a couple of months tops. On top of that I rarely shift at redline or even much after 5500rpms, I was just playing with the new programming to see what it could do.

 

Hell yeah my k03 holds 18-20 throughout the rpm's nicely. When you start to go over 23 psi with the k03 is when it gets inefficient and unreliable. Of course a k03 that has a life of 20 psi isnt gunna be quite as reliable in the long run as the stock 5-7 psi. But lots of people push 20 psi with the k03 for tens of thousands of miles with no problems. With GIAC, its not really ever necessary to go to redline cuz most of the power is down low before/until 5000 rpm's

 

This is my favorite thread, currently.
There's good information in here for me and others.
Does anyone else have info regarding real-world comparisons of the 2 major mfg's on the chip upgrade side?
Thank you to those that have posted already!

 

onepoint8tee, i'm curious how you get 20 psi? I have GIAC and the n75 race valve too and I get around 16 psi. Maybe I'm missing something?

 

I dont know?? Ever since i put the n75 in, i hold at 18-20 psi, but closer to 20 normaly. Before it was more like 17-18. I spike at 21-22 psi. Maybe it has to do with the type of n75 i have and that im DBW?? All I know is that its the n75 that ecs sells, if its the J or H type- i dunno. If you are REALLY curious, ill take a video.