NefMoto

Technical => Tuning => Topic started by: gman86 on October 29, 2015, 04:07:38 AM



Title: Struggling with EGTs
Post by: gman86 on October 29, 2015, 04:07:38 AM
Hi,

I'm trying to get to grips with (what I think is) EGT based torque intervention on my Golf R. Hardware wise, the car is completely stock.

What I'm finding is that projected EGT rises to 999C and the ECU understandably drops load, backs off the throttle and richens up the mixture (0.72). Load doesn't start to return until EGT starts to lower

I'm requesting 0.82 from 2500-3500, richening to 0.8 on peak boost, then dropping to 0.78 from 5000 to redline. Injection time is ~8-9ms and actual is meeting specified lambda.

Load wise, I've raised KFMIRL and capped LDRXN about 10% lower than peak load in IRL. Timing maps are stock, and I've not touched component protection.

Should I be adjusting load to try and keep EGTs down, or does component protection need relaxed on a stage 1?


Title: Re: Struggling with EGTs
Post by: spacey3 on October 29, 2015, 04:23:08 AM
Logs would be helpful (as always).

When does it kick in? On a high gear pull? After running through gears giving it some stick? needs more info/logs - Also, on this car is it real egt (a sensor fitted) or calculated?

If you have 0 cf's you could advance the timing some, which will reduce egt's.

If you have very high cf's you could be making egt's worse and need to back off the timing.

Fuelling looks nice to me, could richen up a small amount though to again combat egt's if they're being a problem still.


Title: Re: Struggling with EGTs
Post by: MIL_on on October 29, 2015, 05:03:06 AM
how does your ldrxn look atm?
Are you sure that its egt based torque reduction?
I don't know if the US spec Golf R has enabled this, but in the Euro Spec Variants its not active (completely set to 99%).
I think what really cuts you is the case that your injection timings are too high and that is why it closes the throttle!
Does your HPFP hold pressure fine?




Title: Re: Struggling with EGTs
Post by: gman86 on October 29, 2015, 06:58:38 AM
Logs would be helpful (as always).

When does it kick in? On a high gear pull? After running through gears giving it some stick? needs more info/logs - Also, on this car is it real egt (a sensor fitted) or calculated?

If you have 0 cf's you could advance the timing some, which will reduce egt's.

If you have very high cf's you could be making egt's worse and need to back off the timing.

Fuelling looks nice to me, could richen up a small amount though to again combat egt's if they're being a problem still.

Yeah I was hoping to get logs via TeamViewer (at work, logs are at home) but my machine is off - typical!

I do all my logging in 4th. ~1500rpm to red line. Getting -3s across all cylinders during pulls so I'm fairly confident I'm as advanced as I can get. Maybe knock a degree off?

I'll try richening up lower down so I can try defer temperature increase. I'll start at 0.8 until the onset of peak boost, then hold 0.78.


Title: Re: Struggling with EGTs
Post by: gman86 on October 29, 2015, 07:04:02 AM
how does your ldrxn look atm?
Are you sure that its egt based torque reduction?
I don't know if the US spec Golf R has enabled this, but in the Euro Spec Variants its not active (completely set to 99%).
I think what really cuts you is the case that your injection timings are too high and that is why it closes the throttle!
Does your HPFP hold pressure fine?




Interesting, from the logs (I'll try get uploaded later), it looks like it starts to drop load as soon as EGT hits 999. Not sure if that's a coincidence or not. It tends to be higher up the revs (5000+)

LDRXN is 206% at 2500, 210% from 3000-4500, 207% at 5000, then 206% from 5500 to 6600. Running unmapped DSG so not tuned load above that

HPFP appears to hold OK. I've upped rail pressure to 120bar. I'd have thought if it was struggling it would be more in the midrange? Injection times are <10sec.


Title: Re: Struggling with EGTs
Post by: spacey3 on October 29, 2015, 08:40:33 AM
Sounds like you have everything covered... I wouldn't adjust the timing at those cf's.

I suppose you've gotten to a point you need to start changing hardware to control them (FMIC, water meth, DP, etc.) or lower the boost some.

Wgdc's all in check? No boost leaks?


Title: Re: Struggling with EGTs
Post by: gman86 on October 29, 2015, 08:53:25 AM
Sounds like you have everything covered... I wouldn't adjust the timing at those cf's.

I suppose you've gotten to a point you need to start changing hardware to control them (FMIC, water meth, DP, etc.) or lower the boost some.

Wgdc's all in check? No boost leaks?

In that case, I reckon I'll need to tone it down a little. I'll trying lowering the LDRXN a little and see where we're at. If it's all good and my CFs are 0, I'll try make up some power with advancing a little.


Title: Re: Struggling with EGTs
Post by: nyet on October 29, 2015, 09:42:15 AM
More fuel, less boost, better timing.

Not much else you can do to solve EGT issues.


Title: Re: Struggling with EGTs
Post by: gman86 on October 29, 2015, 09:47:15 AM
More fuel, less boost, better timing.

Not much else you can do to solve EGT issues.

Yeah I was sort of wanting to avoid that and hope there was a magic bullet to adjust the EGT model. The way I'm seeing it, is the EGT is projected. So once I've fitted a 3" downpipe, uprated cooler and larger intake, the ECU is still going to see said projected EGTs. Unless of course it really doesn't care about them and it's something else that's dropping load


Title: Re: Struggling with EGTs
Post by: nyet on October 29, 2015, 09:51:13 AM
Yeah I was sort of wanting to avoid that and hope there was a magic bullet to adjust the EGT model. The way I'm seeing it, is the EGT is projected. So once I've fitted a 3" downpipe, uprated cooler and larger intake, the ECU is still going to see said projected EGTs. Unless of course it really doesn't care about them and it's something else that's dropping load

Well, if the model is good (and it usually is; you can find out by doing the wideband egt hack) then there is no need to modify the model, just need to change BTS fueling and the load intervention path.

If the model is bad, you can still just fudge the BTS fueling and load intervention..


Title: Re: Struggling with EGTs
Post by: gman86 on October 29, 2015, 10:31:17 AM
Well, if the model is good (and it usually is; you can find out by doing the wideband egt hack) then there is no need to modify the model, just need to change BTS fueling and the load intervention path.

If the model is bad, you can still just fudge the BTS fueling and load intervention..

Such a thing is possible on TFSI engines with MED9?


Title: Re: Struggling with EGTs
Post by: nyet on October 29, 2015, 10:46:58 AM
Such a thing is possible on TFSI engines with MED9?

Good question: I have no idea.