Hey guys, just need some insight. Ive asked something similar before but to star, I have a 2012 gti, 3inch billyboat full turbo back exhaust with nuespeed air intake, and a custom stage 2 tune(custom was needed because this specific guy tuned out my downstream o2 sensors so the codes would go away). I'm pushing 18lbs of boost...(on a good day, normally it's like 16). Seems way to low for stage 2, this guy told me I'd be getting like 20lbs of boost. All I see online is people getting 20-22 with a stage 1 tune. Did I get ripped off or is something else going on. I'm so confused as to how people are getting 20+ with a stage 1 tune and I'm barely hitting 18 with stage 2. Helpp
6
Need help from a tuner on here
- Thread starter GtiDom25
- Start date
I can't remember what he used but no it wasn't eurodyne. I had went with him because originally other tuning companies wouldn't touch my car until I got rid of a couple codes I had. I tried everything to fix them and I couldn't, I was introduced to this guy through someone who worked for unitronics and said that he does custom tunes and can tune out codes. So he tuned out the codes I had by completely tuning out my downstream o2 sensors.
Need a laptop and a diagnostic tool. This is what most of us use. Ross-Tech
With this code you can diagnose problems, see codes and clear them along with a zillion other things. Super useful. And yes you can log various aspects of your car such as boost, fuel pressure etc. and see if the requested and actual are close. Requested is what you tune is asking for.
I put up a youtube video a while back on logging with this tool.
SnailPower
Autocross Newbie
Lol, nobody on Stage 1 is hitting 20-22lbs of boost. That is more like Stage 2+ ish (k04) type of numbers. I think with Stage1 I was hitting around 15lbs. Stg2 is more like 18-19 but overall it's the way power is distributed that the difference is. Stg1 you get a quick punch that falls flat relatively quick, while Stg2 holds onto the power a bit longer to redline and is smoother overall than that quick punch Stg1 gives you.
thatspsychotic
Ready to race!
This is the correct answer. I routinely see higher boost on my gauge when ambient temps and dew points are high in the summer, and lower boost in the winter on the same tune. Gotta think in terms of mass flow rate, where less boost pressure is required to achieve the target mass flow rate when intake temps are colder.
Also, how you're measuring boost is another major factor. If you don't have VAGCOM or some other high quality monitoring, then you're either at the mercy of a.) the accuracy of your boost gauge if you have one b.) if you use something like the Torque app with a bluetooth OBD2 dongle, Manifold Air Pressure generally isn't made directly available over OBD2, so any boost figure you get from OBD2 is a calculated value which is of course prone to errors.
tl;dr manifold air pressure (boost) doesn't tell the whole story, manifold air density is the real metric.
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