cam timing and chain stretch
Turbo Mini Forums

hi, i am going to time my cam in tomorrow. its a billet sw5i. the timing number is 107 degrees.

vizard mentions in the yellow book about timing one further degree to allow for chain stretch.

most cams i see need to be timed to 106. does the 107 degrees given by swiftune take into consideration an extra 1 degree for chain stretch?

am using piper steel lightweight vernier duplex timing kit, so can time to the exact degree.

basically, should i time the cam to 107 or 108 degrees?

thanks

A chain stretches 2 degrees, so time it at 105 so it stretches to 107

Paul

I seriously doubt it!

We had to put a 5 degree ofset key in the van's engine to get the MG cam timed to 107 - must be a very much used chain that we have!

My experience with MG Metro cams is that they all need LOTS of advance. Nor sure if it's the grind, but it seems that they are timed to 110degrees "dot to dot"

Sounds about right V. We started with a 3 degree key, but it was still 2 degrees out...

Ours is timed at 108

If something is worth doing, it's worth doing half of.

yes the chains was worn andy,

the timing on the mg cam V was spot on on the grind. we timed the cam to 108 on this engine there was 3 deg stretch on the chain but its done 80 plus k

thanks for the reply. as its going in an mpi engine, maybe i would be better off timing the sw5 to 106 degrees?

have heard that the mpis (obviously with the cam sensor) are quite tempremental with cam changes/timings.

after how many miles would you expect a 2 degree chain stretch?

the chain came with piper gears, and was supplied by min-its, so hopefully this wont be one of ther cheaper made chains.

thanks

Edited by welshdan on 1st Nov, 2009.

I stretch mine 2 degrees within 300 miles but thats hard driving, conservative driving could be upto 800 - 1000 miles

Paul

I seriously doubt it!

so my best bet would really be to time to 105 degrees. the only thing i worry about is the engine running due to the rover mems and discrepency in timing before it has run. would 2 degrees make a difference to the running of an mpi car? thanks

nope!

If Carling made Mini engines
it would probably be like this one!

http://www.turbominis.co.uk/forums/index.p...tid=229355&fr=0

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

cheers. think im going to go for 106 degrees,allowing for 1 degree stretch, as there is conflicting evidence on this one. ta