The E30Zone tech article recommends adjusting the valve clearance to 0.25 however the engine optimisation article on e30.de recommends 0.35 on intake and 0.30 on exhaust.
What is the right answer, or is there no right answer in this case?
Or should I say what are the benefits of using 0.35/0.30 over 0.25 all round?
M20 Tappets 0.25 or 0.35/0.30?
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JazzMan
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e30_Turbo
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I set mine ( at the 4th try ) to .25 and it's much quieter than before, also found one of the eccentrics was on the wrong way round, much better now.
I would think 0.25 is as close as you would want to go but having only ever done mine I have only that experiance with.
I'm due to sort a neighbours 520i over the weekend and I'm gonna watch this post as I was thinking .30 for his to start with.....wonder what everyone else does?
Mark.
I would think 0.25 is as close as you would want to go but having only ever done mine I have only that experiance with.
I'm due to sort a neighbours 520i over the weekend and I'm gonna watch this post as I was thinking .30 for his to start with.....wonder what everyone else does?
Mark.
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kidsinister
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Bentley manual says 0.25mm when cold, 0.30mm when hot.
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JazzMan
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The wording of the article suggest that "the engine runs and feels noticably better with slightly more gap than is recommended" it suggest the you should try .35 on intake and .30 on exhaust as it "makes a noticable difference to the noise level" - it only recommends that you try these values and see if it make a difference to the running of your engine 
LinkVentilspiel
Der erste kleine Schritt in Richtung Optimierung erfolgt nun. Es stellte sich nämlich heraus, dass die BMW Motoren mit etwas mehr Ventilspiel als vorgeschrieben, spÃarbar besser laufen. 0.35 einlass- und 0.30 auslassseitig solltet ihr auf jedem Fall mal probieren. Einen deutlich hörbaren Unterschied in der Geräuschentwicklung gibt es hierdurch nicht.
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BMW_YARD
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For twelve years I've always set valve clearances with the engine piping hot, and got them running sweet.
Only softies set valves cold!
Setting them on the wide side, gets a more stable idle and can reduce the HC ppm's in the exhaust, always a good sign of an efficiently running engine, or as the krauts would say 'optimized'.
A tight valve clearance is one of the reasons for an uneven idle.
Only softies set valves cold!
Setting them on the wide side, gets a more stable idle and can reduce the HC ppm's in the exhaust, always a good sign of an efficiently running engine, or as the krauts would say 'optimized'.
A tight valve clearance is one of the reasons for an uneven idle.
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jonbuoy
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Did mine today, set them at 0.25 when she was cold. Did'nt have much choice as i was doing it between job's at work 
She run's sweet as a nut now, no loud tappet's and my idle problem has gone out the window, much better!
As "BMW_YARD" said, a few of my valve clearance's were too tight and i had about 4/5 too lose which was causing a rough idle............................not anymore!
She run's sweet as a nut now, no loud tappet's and my idle problem has gone out the window, much better!
As "BMW_YARD" said, a few of my valve clearance's were too tight and i had about 4/5 too lose which was causing a rough idle............................not anymore!
