timing.......
Turbo Mini Forums

a simple question, but my theory need to be confirmed
I'm using 106? lca pulleys (std metro turbo), I want 112 at full lift.
I'm thinking to retard the timing by one teeth ( 360/40 teeth equal 9?) giving 115? and then using a 3 degre tab; so full lift at 112 .
am I all ok?or i missed something

please don't ask why not a 6 ? tab, I only have one 2 and one 3 ? tabs
fab

well what i've found is for some reason it doesn't always work out right, if you put a say 4 deg key in it doesn't always retard/ advance by that amount, it's always best to do it and check it after untill it becomes right.

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Fab,

no I won?t ask that but why do you wish to retard the cam ?

Jukka

Hi fab, your theory is right. But as Miniwilliams is saying, it will not always follow the theory. In the same way I dregreed my 274i.

Harry

Bimmer Twinky headed and turboed A-Series:
http://www.minifreunde.at/harry/projects.htm

Hi, harry
th for the confirmation,
did you timed your at 112? too or did you make some tweak with this ?
fab

Hi Fab,
last season I timed it at 111?, this season I will try 109?, but to be honest, I don't really expect a big difference.
The interesting thing is that my second 274i was exactly the same amount off the 112? it should have. I guess this is because the regrind has a wider LCA than the standard cam it was made off.

It was a lot off, so I had to move one tooth on the sprocket and do the rest with offset keys. (This time I sweared to buy an adjustable kit next time)
cheers
Harry

Bimmer Twinky headed and turboed A-Series:
http://www.minifreunde.at/harry/projects.htm

Hi Harry
"The interesting thing is that my second 274i was exactly the same amount off the 112? it should have"
sorry harry I don't understand, (still some pb with my english) do you mean that you didn't need to use any tweak to degre your cam?, but only the std 106? pulley

cheers
fab

ps: about englishs , are you ready for the "xv de france"?

Hi fab,

When I degreed my first 274i cam, full lift of inlet valve No1 was at 121?. But last season I had a bad follower which damaged my cam, so I bougt a new one. When I degreed the new (2nd) 274i I had again full lift at 121?. This measurements were taken with exactly the same duplex gear set at standard (dots on sprockets aligned) positions. So I had to move one tooth on the sprocket + using offset keys to time the cam correctly. I think you have a similar problem?!

Harry
PS: Sorry, I never learned the french language; you should come to Vienna to teach me fab!!

Bimmer Twinky headed and turboed A-Series:
http://www.minifreunde.at/harry/projects.htm