G60 AFR Wideband Logs 68mm VS 65mm Pulleys

[Riley 0]

Just thought i'd pop this here for anyone interested :thumbleft:

 

 

The specification being logged:

Ported charger.

68mm pully.

RSR Charger outlet.

Boost return deletion.

Heavily ported/polished and dewedged throttle body.

Sierra cosworth FMIC.

SNS 5.5 chip.

Ford red tops injectors - 312cc @ 3bar and 14.5ohms.

Porsche 3.5bar fuel pressure regulator.

 

 

First Run (Three logs): 60mph 4th gear to WOT through to 5th gear.

Log 1:

 

 

Log 2: Showing only the WOT and gear change from above.

 

 

Log 3: Showing the average AFR's of the above.

Min: 10

Max: 22

Average: 12

 

 

Second Run (Three logs): 80mph 5th gear to WOT.

Log 1:

 

 

Log 2: Showing only the WOT from above.

 

 

Log 3: Showing the average AFR's of the above.

Min: 11.9

Max: 12.8

Average: 12.3

 

 

So the most important part of all that is the bottom log, showing only full throttle (WOT) in 5th gear. With a minimum of 11.9AFR, Max of 12.8AFR (Perfect!!!!!) and Average of 12.3AFR (Slightly rich but good!!!) it shows that we are safe running this spec fueling wise.

 

 

And onto the 65mm Pulley

 

 

Fitted the new 65mm pulley along with new belt and small charger timing belt. Initial thoughts on driving home in traffic revealed an issue...As far as logging/measuring It gets to 'X' speed much quicker lol. It feels very much more pokey/faster and actually runs better! Especially at tickover and as far as throttle response (rpm rises quicker)

 

 

 

 

 

 

Anyway, onto the logging with the 65mm pulley. Same runs as before.

 

 

First Run (Three logs): 60mph 4th gear to WOT through to 5th gear.

Log 1:

 

 

Log 2: Showing only the WOT and gear change from above.

 

 

Log 3: Showing the average AFR's of the above.

Min: 10

Max: 19

Average: 12

 

 

Second Run (Three logs): 80mph 5th gear to WOT.

Log 1:

 

 

Log 2: Showing only the WOT from above.

 

 

Log 3: Showing the average AFR's of the above.

Min: 11.7 (.2 drop)

Max: 13.3 (.5 rise)

Average: 12.4 (.1 rise) Good!!!

 

 

So at wide open throttle in 5th gear, the 68mm pulley has an average AFR of 12.3 and the 65mm pulley has an average AFR of 12.4! All good. But the interesting thing is that the 65mm pulley runs leaner initially at full throttle. You can actually feel this as it seems to have more of a surge, and I'd say on the 68mm it felt more flat even though there was more fuel!

 

 

You can see this on the below image where I've put the 68 and 65 side by side, notice the 65mm runs leaner at initial wide open throttle. The red line running across is 12.8AFR, which most consider ideal fueling at WOT.

 

 

And there we have it...some 'rough' logs/results of 68 VS 65 pulleys.

 

 

Neil.

[Riley 0]

Can anybody else see an issue here? I'm pondering over the initial lean spikes at WOT...

[owen g60 10]

Seems normal to me.

The sudden increase in boost due to the throttle body closing will cause a some spiking.

It will take the ecu a moment to adapt the fueling to suit.

 

I would only be concerned if it remained lean.

[Riley 0]

Seems normal to me.

The sudden increase in boost due to the throttle body closing will cause a some spiking.

 

That's what I'm unsure on Owen...The lean spike is actually happening when the throttle body is fully open, WOT switch activated and hitting WOT map on the chip. Hmmm. Just thinking about my 20,000 year running issue, and wondering if it's there showing it's face on the logs.

[owen g60 10]

That's what I meant.

There's going to be a few spikes at wot as the fuelling adjusts from the oxygen sensor and lambda probe.

It's far worse without the 5.5 chip.