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Symptoms of cam timing a tooth out?


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I took my Schricks out last night and put the standard cams back in.

All went swimmingly....engine at TDC, leading edge of the chain on the front sprocket tight, horizontal cut outs on the cam lined up correctly (using VAG tool) etc. I was happy everything was as it should be.

It was getting late so I forgot to flip the crank round a turn and double check the timing was still OK, and just bundled the top end back together again and started her up.

She caught instantly and settled to a smooth idle. Jolly good I thought.

Drove off....feels nice and torquey...got to 4000 rpm and nothing! Just a weird engine note and a reluctance to rev.

Have I advanced the cam sprocket a tooth accidentally? Would explain the boosted low down torque?

I should mention I'm still running the AMD throttle and remapped ECU (for schrick VGI and cams) until I can source spare standard ones. This wouldn't be causing the 4000 sluggishness would it? I wouldn't have thought the map would be aggressive enough to make a standard engine very sluggish at the top end....unless it was retarted too much to stop the VGI causing pinking....

Anyway, just wondering if anyone knows the symptoms of the timing being off? I would have expected reluctant starting and a rough idle if it was out, but this isn't the case?

Think I'm gonna have to strip it again.....bugger....but I'm waiting in vain for someone to say "Nah, your timing's fine mate, it's something else". :)

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maybe the hall sender as andrew says, but i would think the map is not helping, bearing in mind, its a tad coincedental that at the 4k switching point of the schrick vgi, its becomes a problem. without stating the obvious i would have a check with vince first of all to see if there is and correlation in this theory! people running chargers with maps and removing them due to probs can still run the cars but off boost or probs will occur, the same could surely be expected of car mapped to produce some 30lbs/ft of torque more than standard and suddenly have it removed from the procedures?

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Cheers for the responses guys...

I retackled the job on Thursday night and I had indeed been a plum. I somehow managed to advance the cam timing a tooth. It's all too easy on this engine if you're tired and not concentrating fully!

Luckily I only did about 40 miles with the timing in this state, so no lasting damage will have occurred...hopefully!

The cam trigger wheel costs £7 and yeah I always replace those as they usually crack when you crank off the sprocket bolt.

So to answer my own question then, the symptoms of being a tooth out are fairly normal running but doesn't like going over 4000rpm!

If you are on the ball and sipping red bull to keep you awake, then VR6 timing is childs play.

K

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