850r timing help

neil wilton · Post by **neil wilton** » 21 Jan 2011, 03:18

Need help 850 turbo lads and ladies.ive just advanced my exhaust cam 3-4 deg and put my inlet cam in the centred position on the cam wheel may bee 0 deg as per pics and information as found on this forum.
Now heres the questions ,car has way more power in mid range and top end (awsome).but now my 850 r boosts to 16-17 psi between gear shifts and 1/4 part throttle on a standard ecu. as have done this to the cams by eye..
why???? and have i timed up my car correct???will this effect reliability of the engine???

thanks 850r newbei.....

Post by **precopster** » 21 Jan 2011, 07:19

I can't recall any of the posts suggesting this be done and certainly not as a means of gaining performance.

Can you take the cam cover off & post a photo of exactly how you advanced it 3-4 degrees?? Are you referring to the slots for the cam sprocket bolts??

Post by **jimmy57** » 21 Jan 2011, 09:15

I have not used this on turbos but a 95-96 960 wakes up at low end if you rotate its intake cam forward 2.0 -2.5 mm.
That is using a scribe to mark at least one bolt before you loosen bolt and then re-clock it to the right so the bolts move from the mark 2.0 to 2.5 mm and then re-torque the bolts.
The 1 st gen 960 (-->'94) has the higher output engine with more valve lift and I'm not sure of the effects on that one.
The first gen had the revision that could be done for idle improvement where the intake was advanced and exhaust was retarded through use of a different cam timing tool (black one issued to dealers). As I recall this improved low end on those.

To answer the OP, Any time the power level goes up the stress increases so there are effects on longevity. THe extent of these effects is under the control of your right foot. Driving down the highway at the same speed requires the same power so no effects. Pedal matted to the floor every time you go from stop enjoying the newfound ponies under the hood will have great effects on the whole powertrain.
The position within the available slots on the cam gears is not a reliable way to gauge "intake cam centered". If you moved from there and put it back there then yes. If you put it in the center of the slot then on some cars that is retarded and on others it is advanced. The available slot width and the pitch of the cam gear teeth allows those gears to be installed in two places. One is slot open left of bolts and the other is slot open right of bolts. The gear marking is added after assembly only for timing belt changing so the mark isn't a punched in manufacture of gear marking.

neil wilton · Post by **neil wilton** » 21 Jan 2011, 11:50

thanks guys
what i did was slightly loosen the three bolts on the exhaust cam as the bolts in the slots where 3/4 of the way to the left in the cam slots and moved the cam so the bolt ended up being 1/3 into the right side of the cam slot,and centred the cam bolts on the cam slot on the in let cam.
and now the car has more power and more of a rush as the car goes past 3000 rpm all the up to red line.
but now over boosts on a standard ecu and hits fule cut off between shifts or 1/4 throttle.and thats one place where the power realy is now. boost presure can get up to 16-17 psi+.

Post by **jblackburn** » 21 Jan 2011, 11:55

How are your vacuum lines to the turbo control valve? When my one to the compressor side of the turbo cracked in half, I had the same thing happen, but man it was fast!

neil wilton · Post by **neil wilton** » 21 Jan 2011, 12:27

how do that was a fast reply..all my vac lines are nearly new and are of the silicone type. boosting changed as soon as i reset the timing. and have checked all vac lines etc.

Post by **jimmy57** » 21 Jan 2011, 13:30

If you cut the wire between ECM and TCM on 94-98 for torque reduction for low gears and winter mode, you readily take off with spinning tires and smoke. The problem is the auto trans is probably VERY UNHAPPY and when you try to drive normally the amount of throttle that gives the big show and the amount that just gets you moving a little briskly is a faint difference and you'll end up in a cloud of smoke in a funeral procession or in front of a LEO at the grocery store.

neil wilton · Post by **neil wilton** » 21 Jan 2011, 14:46

how do i cut these wires and where do you find them,and could u put a switch on these wires to turn off tyre shredding mode and switch it back for wife and kid mode....

thanks