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Zetec Cam Timing!
coozer - 12/3/10 at 11:22 PM

Just installed a vernier on the exhaust cam of my ST170 engine...

Checked the cam timing before I changed it and the inlet cam was way out!

Set it up with the new vernier, turned the crank and checked.. inlet out again. Adjusted it, turned crank, inlet out again!

Seems the inlet cam being vvt it has a bit of lash, I can wobble the cam wheel and it doesnt turn the cam. So I thought it needed loosen off to adjust but it has a weird bolt head under the external cap, anyone know what this is?

Anyway the cam is only out a little bit now, advanced slightly, and thought well, the vvt advances anyway so set it up better than the oem and retarted the exhaust cam 8° as advised and started it up..

No idle, started and dropped out.. so bit more fuel, adjusted the idle screw, calibrated the tps and now it idles like a dream, smooth and quiet.

Can't believe how much better it is for tweaking the cam timing, now I believe a lot can be gained from a dyno set up. When I can afford it!

Steve


RichardK - 12/3/10 at 11:27 PM

Can things get any better in Steves's world?

Glad to hear that the cam timing has helped, having everything spot on certainly helps the overall running of a motor, could never really understand why oems never seemed to bother, it seems like they had a "thats good enough attitude".

Anyway, glad you're making progress. Cheers

Rich


coozer - 12/3/10 at 11:29 PM

Ready to go out now, 28th is the target, I want it sorting to get down there... just need some dry weather!!!!!


Dusty - 13/3/10 at 03:23 AM

Effectively with no oil pressure in the system you have 30 degrees potential movement of the inlet pulley on the cam. Just need to make sure the pulley is fully retarded when the cam locking bar is in place. How much have you altered the exhaust timing? Is that 8deg retarded?
Have to admit I have not dared to unbolt the vvt pulley yet. I would like to replace it with a vernier also.


coozer - 13/3/10 at 03:48 PM

Exhaust is -8. Been out today for the first time with the efi and have revved it hard with no problems.

Intake noise is very loud, reckon it would fail SVA!