How's the knocking???? Did you tune it??

Do you need full throttle at that speed all the time or could it go faster when higher geared???

I am not sure as still get slight knock if I give it full throttle so backed off and let car build up speed to max limit. Oil temp was around 98 deg in rocker cover where oil feed returns from Turbo. Stopped after run and had a look at spark plugs - they looked good colour (better when wide band LAMBDA sensor arrives - hopefully before SPA).

I would put the lambda probe after the turbo at the red marked spot (looking at your pictures)

Wide band Lambda sensor kit arrived today - only had time to mount the sensor in the exhaust and run the cables. Will finish tomorrow after work.

Don't drive without a working probe, otherwise it will be destroyed.... Only let the engine run when proper connected and working...

Finished Lambda sensor yesterday and spend the morning tuning the carb needle (reprofiling with 600 fine wet and dry) to get best fuel/air ratio over rev range. Fuel/air ratio between 14.2 and 15 over most of rev range. @ 90- 115 kph ratio is stuck at 14.5. Tried to increase advance from 5000 -6000rpm on 1-2 spark to 21 and 22 but very slight knock on motorway hill so put it back to 19 for 5000 and 6000. I think that is it for now - just drive it and enjoy.

Under boost the arf has to be around 12,5 for maximum power. Because the fuel will be a little rich, the unburned fuel cools the "burning chambre"??? down preventing knock and making maximum power.

14,7 is only for environment making emisions as low as possible.... but maximum power is at arf 12.5 (esspecialy for boosted engines) and driven with petrol.

E85 and lpg have different ratios.....

You can try waterinjection too this will even produce more power ......


Under light throttle arf can be up to 16 if your engine can handle it, to lean and your engine will hold in, go along, hold in, go along a.s.o.


There are whole books written about this subject.........


Take a look here http://www.megamanual.com/v22manual/mtune.htm

I have tried to get the afr lower but the car will not pull away smoothly. The gauge supplier states - 10- 12.9 lean, 13- 17.9 optimal and 18-20 rich
So I set it roughly in the centre around 14.2/14.5.
Will keep an eye on it and see how it goes but checked plugs after 20 kms on the motorway at 14.5 afr and they were brown (rough test I know)

D6 76
Most of this thread has been beyond me, however it does seem to me that those figures you've quoted for AFR might be back to front...

ken

You are just a fraction quicker...

lower is richer, higher is leaner!!!!