Bumble is poorly....

Going back to the discussion about the flywheel chatter, it may now be as bad as all that to be fair.

As some of you know I have been running with no lambda connected for the last 6 months as the injector scaling has been out of whack. The map was for 550s and I was running 630s. Unisettings was set to pull 20% of fuelling out to compensate. This meant that with the lambda connected, it would just adjust the trims and screw the fuelling up.

I've been away for the last week and whilst I was Bill scaled the injectors on the map for me properly. This means that I now and back using lambda control.

One of the side effects of running with no lambda and different injectors is that the fuelling on idle was rich, meaning it was also unstable - very jumpy.

I think it was this idle instability that was causing that chatter. As soon as I plugged the new lambda in to test after fitting, the chatter was almost instantly gone.

I think Bill has also tweaked the idle up slightly on the map, and this combined with lambda control has practically cured the chatter altogether....

Maybe it's not as bad as all that after all.... :thumbsup:
 
Very good to hear mate. So now the chatter has gone would you recommened the smf or not?
 
Very good to hear mate. So now the chatter has gone would you recommened the smf or not?

Still not sure. There are things about it that make me suggest not. The negatives seem to outweigh the positives.

It revs up REALLY fast. Touch the throttle in neutral and you're at 3K before you know. Makes driving a bit tricky as rev matching is hard.

Also, hill starts are now a real ballache as she does really want to stall.

Hill climbing is far better with the SMF.
 
I wonder what causes the chatter? Imbalance? It's only something I've heard about with 1.8Ts. Can you get round it by adjusting the idle compensation in vcds?

So raising the idle huh ;)

I wanted to raise mine slightly as the VF dogbone can be quite bad without the AC on but haven't got around to doing it yet.
 
You can raise idle with UniSettings... I upped mine in the map to 880rpm as this is where I had it set in unisettings before...

<tuffty/>
 
So raising the idle huh ;)

I wanted to raise mine slightly as the VF dogbone can be quite bad without the AC on but haven't got around to doing it yet.

To be honest dude, it was better at previous idle - it was the fuelling being too rich at idle that caused the jerking of the engine, and consequently the gearbox.

Idle being upped has improved it further :thumbsup:, but the fuelling was the main issue there.

And yes, Unisettings should be map independent.
 
How do the 630's run? Read that there not that good, I've got 630's on the new build but now worried they might not be that good, 550's where awesome so just a little anxious about fitting these
 
I run 630's and they are ok... the reports I have read about suggest that idle is an issue but idle on mine seems fine... you need to dial TVUB in of course...

I did consider using 550cc Bosch with a 4bar FPR as I have an inline pump and the Bosch injectors are allegedly 'better' atomisation etc... they also do a 750cc version of the Bosch but... the set I have seen (used on the 2ltr stroker LCR Bill had in recently) had 750cc scratched into them and the same part number as the 550's so not sure what tomfoolery has gone on to make them flow more and I haven't found any info out to back up the claims or what differences made to TVUB values that are already fairly well documented..

The one claim I have seen of the 630's fouling over time is cobblers IMO... mine are clean as a whistle and have been in since I first did my BT conversion... I think thats more subject to PVC deletes and stuff and the context can be difficult to follow on Nef as they often refer to 30v tuning rather than 20v tuning... no idea how much of the PCV etc is traditionally removed on those builds..

<tuffty/>
 

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