Stock boost?

thanks for that!! - I took some logs on VCDS.. to convert the mbar figure it has to PSI boost pressure - can anyone confirm that the below is correct:

(VCDS mbar) multiplied by 0.0145037737730209 (conversion factor) - 14.4 (atmospheric pressure in PSI) = ACTUAL PSI

VCDS mbar * 0.0145037737730209 - 14.4 = actual PSI

So looking at my logs and working it out on the above calculation - peak my car saw:

1720 mbar * 0.0145037737730209 - 14.4 = 10.5 PSI (which sounds about right??)
 
Nope, your car has a K03 turbo where by the car in this thread has a K03S which has a bit more puff :)

A stock KO3 car is about 8PSI I think so you're alright there.
 
Aums come standard with a k03s but are still 150bhp/ps.

Im sure bill or welly will be able to shed some light on this. Or do a google search and it will come up with uk mk4's forum theres bound ton be proof on there
 
Jordan1.8t said:
Aums come standard with a k03s but are still 150bhp/ps.

Im sure bill or welly will be able to shed some light on this. Or do a google search and it will come up with uk mk4's forum theres bound ton be proof on there
Click to expand...

Nobody is denying that and fingers crossed everybody knows that, Tom has an AGU and is more than aware of the differences. Must have got his wires crossed. :)
 
Last edited:
I genuinely thought KO3S cars were all 180bhp! :asskicking:

So no need for me to go and 'prove' what you're saying is right you touchy little thing!
 
Lol. Just thought id try explain :)

Its the auq engine that usual is the 180bhp version. Found in golf mk4 anni's and dare i say a3 quattro's??

But i did some research last nite and it seems 8psi is about right for a 150bhp model. According to
Some threads i read over on uk mk4's
 
I just thought it seemed a bit random by sticking a KO3S on there and still keeping the car at 150bhp?.

Every day's a school day!
 
10.5psi is way over stock.

Both the ko3 and ko3S will bost to 7-8psi MAX on a standard 150bhp car.

Also, conversion for PSI: BAR is 14.7:1 at sea level, not 14.5 :)

Nothing wrong with your car Jordan, 8psi is fine.
 
  • Like
Reactions: pangsterA3
Prawn said:
10.5psi is way over stock.

Both the ko3 and ko3S will bost to 7-8psi MAX on a standard 150bhp car.

Also, conversion for PSI: BAR is 14.7:1 at sea level, not 14.5 :)

Nothing wrong with your car Jordan, 8psi is fine.
Click to expand...

Hi Prawn,

Thanks for the reply! :)

I've plotted an extract of the values from the log I took in VCDS (kept it in MBAR) against revs:

A3_BOOST.jpg


Does the above look ok/healthy for a stock 1.8T AUM with KO3S?

Is there any other functions I can use in VCDS to check/log against as I think I used Group 115 for the above which was something you referenced in another post iirc?..

Using 14.7 instead of 14.4 - I'm still calculating an actual peak boost of 10.2 PSI (unless I'm doing something wrong??)

(1720 mbar) * (0.014503774) - (14.7) = 10.2 PSI

I've ran a scan/auto log using VCDS and there was some old fault codes on there (which I've cleared) - ran the above log/plot and then rechecked (no fault codes found)??


Maybe I logged it wrong?... I'll try and do another/proper log when I get a chance and compare results..
 
Last edited:
1750mbar is 1.75 bar absolute pressure.

ie 0.75 bar of boost.

Its just a spike though looking at the graph, it drops back to what looks like 1500mbar, which is 0.5bar or ~8psi of boost.

a 180hp car would hold that 10psi rather than dropping off.
 
  • Like
Reactions: pangsterA3
aragorn said:
1750mbar is 1.75 bar absolute pressure.

ie 0.75 bar of boost.

Its just a spike though looking at the graph, it drops back to what looks like 1500mbar, which is 0.5bar or ~8psi of boost.

a 180hp car would hold that 10psi rather than dropping off.
Click to expand...

thanks aragorn!! - I thought it might be a messy/eratic logging on my part.. I'll try and get a better/cleaner log with a proper clean 3rd gear pull at some point over the weekend and then look at the results! :)
 
I wouldn't worry about it over boosting, my KO3s runs at an unreliable and frankly stupid 26psi. A *safe* level of boost is still as high as 22psi.

I would be looking into why (my thoughts would be boost leak and over compensation) and then get it mapped :)
 
  • Like
Reactions: pangsterA3
16Klappe said:
I wouldn't worry about it over boosting, my KO3s runs at an unreliable and frankly stupid 26psi. A *safe* level of boost is still as high as 22psi.

I would be looking into why (my thoughts would be boost leak and over compensation) and then get it mapped :)
Click to expand...

thanks for the reply! - I'll have a proper/better go at logging so I can get a fuller understanding of how it's performing... I guess I really should be aiming for a good/clean 3rd gear pull from 1500-c6000 rpm and see what the results look like then?..
 
pangsterA3 said:
Hi Prawn,

Thanks for the reply! :)

I've plotted an extract of the values from the log I took in VCDS (kept it in MBAR) against revs:

A3_BOOST.jpg


Does the above look ok/healthy for a stock 1.8T AUM with KO3S?

Is there any other functions I can use in VCDS to check/log against as I think I used Group 115 for the above which was something you referenced in another post iirc?..

Using 14.7 instead of 14.4 - I'm still calculating an actual peak boost of 10.2 PSI (unless I'm doing something wrong??)

(1720 mbar) * (0.014503774) - (14.7) = 10.2 PSI

I've ran a scan/auto log using VCDS and there was some old fault codes on there (which I've cleared) - ran the above log/plot and then rechecked (no fault codes found)??


Maybe I logged it wrong?... I'll try and do another/proper log when I get a chance and compare results..
Click to expand...
my girlfriend wishes to say her thoughts on the above graph
she says this is peoples love life in graph form when they buy their car, then start to come on here, then it all goes to ****.
id say she's pretty accurate
 
  • Like
Reactions: pangsterA3
What's the stock boost for a s3 2000 reg, think that's the k04 ?
 
You must log in or register to reply here.

Similar threads

I
stock boost
Replies
7
Views
976
Ian_83
I
I
210hp S3 stock boost
Replies
9
Views
4K
NWMark
N
g10chy
Stock and remap boost pressures...what should they be?
Replies
5
Views
1K
Welly
Welly
Pasteurised
Stock WHP
Replies
47
Views
10K
<tuffty/>
<tuffty/>
A
Stock cat??
Replies
2
Views
788
drewman
D
Top
Back