Revo Stage 2 Logs PAGE 3 HOLDING CRAZY BOOST***

[James.Judd.1]

Do you have a boost gauge to confirm what the map sensor is seeing ?

Yes. the boost guage is tested and accurate too..the MAP sensor is only about a month old aswell.

 

[Wak]

I checked the actuator and it fully opens at around 7psi.

Most maps ask the turbos for more boost than they can produce.. so basically the turbos are always flat out.. this is exactly what im doing here by setting it at 24psi, making the turbo work flat out, but clipping the overboost.. the fact is these turbos (k03s's) cannot produce 1.35bar at 6000rpm even when they are flat out.. especially as the g/s dont match up to that amount of boost.
This seems like there is something causing back pressure between the MAP sensor and the Inlet manifold.. meaning there is high pressure but not the airflow to match..
BUT everything has been off and checked and this is not the case..

I know what you are saying but if you take a healthy new K04 any run it flat out you "should" easily see 1.2 bar on a 1.8T ( at the top of the rev range), when they are older 1.1-1.2 ish.

If you take the same turbo with a clamped wastegate it can produce 1.4 bar, possibly more. ( obviously not advised and may not last very long)

Are you sure the slightly high after market settings of the actuator and the high demands set by the mbc are not giving you the high pressure but saturated at the limits of flow accross the air mass meter.

A test to try maybe......
Can you set the MBC to 1.1 bar and if you hold 1.1 bar at the redline do you still get a close to 180 g/s figure or does that also drop relatively.?

 

[James.Judd.1]

I know what you are saying but if you take a healthy new K04 any run it flat out you "should" easily see 1.2 bar on a 1.8T ( at the top of the rev range), when they are older 1.1-1.2 ish.

If you take the same turbo with a clamped wastegate it can produce 1.4 bar, possibly more. ( obviously not advised and may not last very long)

Are you sure the slightly high after market settings of the actuator and the high demands set by the mbc are not giving you the high pressure but saturated at the limits of flow accross the air mass meter.

A test to try maybe......
Can you set the MBC to 1.1 bar and if you hold 1.1 bar at the redline do you still get a close to 180 g/s figure or does that also drop relatively.?

Obviously as a test that would be fine.. but I would loose all my low down torque running a flat 1.1bar with no spike.. and thats the best bit about the K03s.. the initial kick in the back

 

[seatcupramad23]

I know what you are saying but if you take a healthy new K04 any run it flat out you "should" easily see 1.2 bar on a 1.8T ( at the top of the rev range), when they are older 1.1-1.2 ish.

If you take the same turbo with a clamped wastegate it can produce 1.4 bar, possibly more. ( obviously not advised and may not last very long)

Are you sure the slightly high after market settings of the actuator and the high demands set by the mbc are not giving you the high pressure but saturated at the limits of flow accross the air mass meter.

A test to try maybe......
Can you set the MBC to 1.1 bar and if you hold 1.1 bar at the redline do you still get a close to 180 g/s figure or does that also drop relatively.?

interesting i love to see the logs when its turned down to 1.1-1.2

 

[Damoegan]

Maybe I am getting confused here but in my "limited" experience if you have a manual boost controller which has a single setting and you set it to 1.65 bar surely its going to try and maintain 1.65 bar accross the whole rpm range !

hence why you have crazy boost! If you want it to run sensible boost from the k03s , for example, run 0.9 bar at 6500rpm then your mbc needs to be set to 0.9 bar no?

Also , is your Air mass meter healthy?( new)

Thats not haw a MBC works.

You set your "set point" to say 1.5bar, the turbo will only give you 1.5bar (if the turbo is capable of flowi g 1.5bar!!) but if the turbo cant flow 1.5bar at xRPM (4.5-5k RPM on a k03s) then you wont get 1.5bar past said RPM...

 

[James.Judd.1]

Took a few logs with reduced boost.. Ill upload them in a min.. only pulling 174g/s max though... BUT it can take a shed load more timing which im hoping brings the power back up

 

[James.Judd.1]

Here we go.. no timing pull what so ever, I must admit it feels better top end BUT not quite as good bottom end now.. hmm

 

[James.Judd.1]

The actual boost is very similar to the requested which is rather strange

 

[seatcupramad23]

Took a few logs with reduced boost.. Ill upload them in a min.. only pulling 174g/s max though... BUT it can take a shed load more timing which im hoping brings the power back up

ok if your roughly pulling the same g/s figures with high or reduced boost why not reduce the boost or am i missing something

 

[Damoegan]

James, copy all the info direct from the excel file and past in in here and add (code) before and (/code) after but replace () with []

 

[James.Judd.1]

ok if your roughly pulling the same g/s figures with high or reduced boost why not reduce the boost or am i missing something

Im pulling roughly the same figures top end.. but not between say 3-5k.. it just doesnt feel anywhere near as urgent.

 

[seatcupramad23]

Im pulling roughly the same figures top end.. but not between say 3-5k.. it just doesnt feel anywhere near as urgent.

mifght be safer to run with lower boost until you get to the bottom of your issue

 

[James.Judd.1]

Tuesday	5	April	2011	20:46:10						
6K0 906 032 AA		1.8L 20VT EU3    01 0002								
										
	Group A:	'020				Group B:	'002			
		Idle Stabilization	Idle Stabilization	Idle Stabilization	Idle Stabilization		RPM	Load	Inj. On Time	Mass Flow
	TIME					TIME				
Marker	STAMP	 CF	 CF	 CF	 CF	STAMP	 /min	%	 ms	 g/s
	116.04	0	0	0	0	116.45	2800	30.1	3.69	16.22
	116.96	1.5	3	1.5	1.5	117.36	2920	105.3	13.94	69.5
	117.76	1.5	3	1.5	1.5	118.16	3120	185.7	24.6	118.81
	118.56	1.5	3	1.5	1.5	118.96	3400	191	25.01	125.56
	119.34	1.5	3	0.8	1.5	119.74	3680	190.2	25.01	135.58
	120.14	1.5	2.3	0.8	1.5	120.56	3960	188.7	25.01	142.69
	120.94	1.5	1.5	0	1.5	121.34	4240	188	25.01	153.47
	121.76	1.5	1.5	0	1.5	122.16	4480	188.7	25.01	161.89
	122.56	1.5	0.8	3	1.5	122.96	4720	188	25.01	169.03
	123.36	0.8	0	3	1.5	123.85	4960	186.5	24.6	178.58
	124.25	0.8	3	3	1.5	124.65	5160	180.5	24.19	177.36
	125.15	0.8	3	3	0.8	125.56	5360	175.2	23.37	180.56
	125.95	0.8	3	3	3.8	126.35	5520	167.7	22.55	177.69
	126.75	0.8	3	2.3	3.8	127.26	5640	163.9	21.73	180.75
	127.66	3	3	5.3	3.8	128.06	5760	162.4	21.73	180.11
	128.56	3	2.3	5.3	3.8	128.96	5880	158.6	21.32	180.39
	129.35	3	2.3	5.3	3.8	129.76	5960	155.6	20.91	178.86
	130.15	3	2.3	5.3	3	130.55	6040	149.6	18.86	178.86
	130.95	0	0	0	0	131.35	4760	9	1.23	6
	131.85	0	0	0	0	132.25	4680	7.5	0	6.97
	132.65	0	0	0	0	133.05	4600	7.5	0	6.78

 

[James.Judd.1]

Thats was my latest high boost one with added timing
if you compare the g/s between that and the low boost log you will see what i mean

 

[ibizacupra]

Are you sure the slightly high after market settings of the actuator and the high demands set by the mbc are not giving you the high pressure but saturated at the limits of flow accross the air mass meter.

A test to try maybe......
Can you set the MBC to 1.1 bar and if you hold 1.1 bar at the redline do you still get a close to 180 g/s figure or does that also drop relatively.?

180g/s is no where near the limit of the 70mm maf tho is it wak?

 

[James.Judd.1]

It was interesting what he was saying about a K04 flat out will produce 1.2bar at the redline.. but with a clamped wastegate its more like 1.4.

Maybe thats why mine is holding more boost.. because in effect my wastegate is clamped, bar the initial spike

 

[joehirth]

Another thing to check, although you say the MAF is new, where did you buy it, is it genuine? Boost would be high but air flow read low if it was faulty?

 

[Wak]

Thats not haw a MBC works.

You set your "set point" to say 1.5bar, the turbo will only give you 1.5bar (if the turbo is capable of flowi g 1.5bar!!) but if the turbo cant flow 1.5bar at xRPM (4.5-5k RPM on a k03s) then you wont get 1.5bar past said RPM...

Sorry, thats exactly what I meant when I said:-
"you set it to 1.65 bar surely its going to try and maintain 1.65 bar accross the whole rpm range !"

A single setting mbc will try to maintain whatever you set it to...... what your turbo will give is another matter.

 

[Wak]

180g/s is no where near the limit of the 70mm maf tho is it wak?

Correct, but I'm trying to offer some test options that may help diagnose this issue hence am interested to see if the g/s will drop with less boost or is it strangled for some other reason.

Also the new Maf you mentioned, is it genuine Bosch or OEM ( not an ebay clone!) , and 100% known to be the correct part number?

 

[James.Judd.1]

Correct, but I'm trying to offer some test options that may help diagnose this issue hence am interested to see if the g/s will drop with less boost or is it strangled for some other reason.

Also the new Maf you mentioned, is it genuine Bosch or OEM ( not an ebay clone!) , and 100% known to be the correct part number?

Yes Bosch and correct part no.
If you look at the last two logs you can clearly see that lowering the boost drops the g/s.. I also dropped it further on another log and it made 160g/s max.