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[Lazydocker]

The lag I get now matches mv6 - full chat,6750rpm gearchange on low gas is horrid

Mv6 fixable with petrol switch at 6500

Interesting.. Mine is annoying at the moment. For a long time it wasn't that noticeable. :-/

I did notice something interesting on the datalogs provided by Jimbob and JamesV6 recently. Right up to 6200 RPM Jimbob's car shows an injector duration of 23-24ms.

Unless I'm very much mistaken... At 6000 RPM the engine turns once every 10ms. Each cylinder fires every 20ms. How can you inject fuel for 24ms?

Either the figures reported by the ECU are dangleberries or the injectors are maxing out - which makes me wonder if they are being held open continuously. The LPG ECU then has nothing to trigger on and gets in a muddle.. perhaps? :-/

Kevin

But we've seen the LPG pressure overshoot when the injectors shut down for the change :-/ :-/

Mine hadn't been too bad but has started being a little annoying in the last day or 2, although I am very low on LPG at the moment

[feeutfo]

The lag I get now matches mv6 - full chat,6750rpm gearchange on low gas is horrid

Mv6 fixable with petrol switch at 6500

Interesting.. Mine is annoying at the moment. For a long time it wasn't that noticeable. :-/

I did notice something interesting on the datalogs provided by Jimbob and JamesV6 recently. Right up to 6200 RPM Jimbob's car shows an injector duration of 23-24ms.

Unless I'm very much mistaken... At 6000 RPM the engine turns once every 10ms. Each cylinder fires every 20ms. How can you inject fuel for 24ms?

Either the figures reported by the ECU are dangleberries or the injectors are maxing out - which makes me wonder if they are being held open continuously. The LPG ECU then has nothing to trigger on and gets in a muddle.. perhaps? :-/

Kevin

Seem to remember discussions that the issue may be routed in the car, rather than lpg related. We have witnessed lag on petrol, and TB reports same with his DBW.

[Lazydocker]

The lag I get now matches mv6 - full chat,6750rpm gearchange on low gas is horrid

Mv6 fixable with petrol switch at 6500

Interesting.. Mine is annoying at the moment. For a long time it wasn't that noticeable. :-/

I did notice something interesting on the datalogs provided by Jimbob and JamesV6 recently. Right up to 6200 RPM Jimbob's car shows an injector duration of 23-24ms.

Unless I'm very much mistaken... At 6000 RPM the engine turns once every 10ms. Each cylinder fires every 20ms. How can you inject fuel for 24ms?

Either the figures reported by the ECU are dangleberries or the injectors are maxing out - which makes me wonder if they are being held open continuously. The LPG ECU then has nothing to trigger on and gets in a muddle.. perhaps? :-/

Kevin

Seem to remember discussions that the issue may be routed in the car, rather than lpg related. We have witnessed lag on petrol, and TB reports same with his DBW.

The issue is definitely with the car(s) behaviour, just amplified by the LPG... I'm still scratching my head to minimise the amplification... I'm sure with some of the extra features on the Plus ECU it can be tuned out :-/ After all... There was no Lag whatsoever when we were tuning it on Sunday night (admittedly with a full tank of LPG) so there must be something we can do

In fact, the only lag we noticed on Sunday evening was when running on petrol

[Kevin Wood]

But we've seen the LPG pressure overshoot when the injectors shut down for the change :-/ :-/

So the LPG injectors shut, but, whilst I can see the ignition retard for a couple of samples in the log, the petrol injector duration stays the same throughout the change.

Just suggesting that maybe the LPG ECU stops seeing injector "events" and shuts the LPG injectors. :-/

Kevin

[Lazydocker]

But we've seen the LPG pressure overshoot when the injectors shut down for the change :-/ :-/

So the LPG injectors shut, but, whilst I can see the ignition retard for a couple of samples in the log, the petrol injector duration stays the same throughout the change.

Just suggesting that maybe the LPG ECU stops seeing injector "events" and shuts the LPG injectors. :-/

Kevin

Stag software picks up a sharp spike (downwards) in petrol injector times which the LPG injectors (obviously) copy, causing the LPG pressure to spike (or overshoot). Then when the injectors start firing again the excess pressure is released by injecting slightly more LPG than should be there, causing a momentary richness which causes the lag.

At least that's what it looks like at the moment... There is the possibility of trying some things when I can get an appointment to visit Teilo again

[TheBoy]

To reiterate, both mine only show lag at 6750rpm gearchanges on low gas (excluding the DBW lift off, reapply issue that exists on petrol)

BOth mine are plus ecus

The 45mph 1st to 2nd is worse, 2nd to 3rd is better, and 3rd to 4th is not noticable

[Lazydocker]

To reiterate, both mine only show lag at 6750rpm gearchanges on low gas (excluding the DBW lift off, reapply issue that exists on petrol)

BOth mine are plus ecus

The 45mph 1st to 2nd is worse, 2nd to 3rd is better, and 3rd to 4th is not noticable

Yep, I realise that was what you mean.

I still think (or is that hope?) it will tune out :-/

[tigers_gonads]

Don't know if i'm barking up the wrong tree here but am I libel to have problems setting the kit up with my manual ?

I do have a rather agressive driving style 

If so, any tips would be apreciated 

[Lazydocker]

Don't know if i'm barking up the wrong tree here but am I libel to have problems setting the kit up with my manual ?

I do have a rather agressive driving style 

If so, any tips would be apreciated 

Nope... Manual has different properties when changing gear so should be fine

Don't forget to order the laptop cable though

[tigers_gonads]

Will do ( now i know too ) 

Thats when he gets back to me 

[Lazydocker]

Will do ( now i know too ) 

Thats when he gets back to me 

Thought you'd heard from him? :-?

Thinking on some more about the lag... I wonder if it's worth calibrating and mapping with a low tank contents :-/

[feeutfo]

Will do ( now i know too ) 

Thats when he gets back to me 

Thought you'd heard from him? :-?

Thinking on some more about the lag... I wonder if it's worth calibrating and mapping with a low tank contents :-/

Assuming vap pressure is not affected? Why does tank level affect it at all?

[Lazydocker]

Will do ( now i know too ) 

Thats when he gets back to me 

Thought you'd heard from him? :-?

Thinking on some more about the lag... I wonder if it's worth calibrating and mapping with a low tank contents :-/

Assuming vap pressure is not affected? Why does tank level affect it at all?

Don't know! It shouldn't TBH Only thing I can think of is tank "slosh" with the liquid moving away from the pickup causing it to just suck vapour :-?

[feeutfo]

Will do ( now i know too ) 

Thats when he gets back to me 

Thought you'd heard from him? :-?

Thinking on some more about the lag... I wonder if it's worth calibrating and mapping with a low tank contents :-/

Assuming vap pressure is not affected? Why does tank level affect it at all?

Don't know! It shouldn't TBH Only thing I can think of is tank "slosh" with the liquid moving away from the pickup causing it to just suck vapour :-?

Though that may explain the switching back to petrol in the corners on my old car, but lag under acceleration only...?

[Lazydocker]

Will do ( now i know too ) 

Thats when he gets back to me 

Thought you'd heard from him? :-?

Thinking on some more about the lag... I wonder if it's worth calibrating and mapping with a low tank contents :-/

Assuming vap pressure is not affected? Why does tank level affect it at all?

Don't know! It shouldn't TBH Only thing I can think of is tank "slosh" with the liquid moving away from the pickup causing it to just suck vapour :-?

Though that may explain the switching back to petrol in the corners on my old car, but lag under acceleration only...?

Your old one also had the added disadvantage of a multivalve though

As for lag under acceleration only... There's no demand for gas under braking