Cam timing nightmare
Turbo Mini Forums

Guys totally flumaxed with timing in my KC500 cam...
The engines on a bench, with the head on, having a nightmare trying to work out how to time in my cam and what am I actually trying to achieve.

I have looked on YouTube at the two videos, the young lad and the American chap, but I m struggling with the concept and feel that when they blast through it so quick that I miss the detail..
Also looked at the description on here and it doesn't make sense.....I'm really stumped...

Vizards book completely losses me... My problem is which way am I turning the crank, at what point..

I get the cam at TDC...sorted and protractor set to 0deg
I get the DTI on no2 push rod to find the highest point ....sorted
Its the whole 5thou one way then turn the crank which way-aaaraarargagah..

Any help please....
It's a kc500 cam on a 1380 turbo reading other posts it should be timed In at 108

Sorry crank at TDC....not cam

Nevermind I've confused myself, you need to rock the crank using the dti on the piston to find exact tdc, then I can't remember the rest as it's been a while since I last did one!

Edited by Carlzilla on 1st Mar, 2014.

you turn the engine clockwise looking at the waterpump end,



you cant just put the engine at TDC and slap the protractor on to get an accurate figure as the piston dwels at TDC. you need to put a DTI on the piston and make sure you have the same degree's and reading on the DTI either side of TDC.
e.g. turn engine so the protractor reads 10de BTDC note the reading on the protractor... turn it to 10 deg ATDC note the DTI reading.... if they dont match move the protractor and repeat.

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=4769

Hi joe
Thanks for the TDC info.... I think I'm ok on that one....it's the actual cam timing bit I'm stumped at.... Can some one tell me how to do this part, please tell me which way the crank is going as well as The DTI readings....thanks guys...and joe

Well the protractor reads 0 through the 360. Cam number two (from the end of the face you are looking at/the first inlet lobe) lobe needs to be at the peak of it's lift and halfway through its dwell, then I would rotate the crank clockwise to reach the desired degrees of timing, if you overshoot it, rotate it back about 1/4 turn and rerotate the crank clockwise again to the desired timing. The reason for this is because I like to play it safe and accounts for slack in the timing chain when checking the timing once/if the chain is on.

Edited by Carlzilla on 1st Mar, 2014.

Ok for the actual cam timing,

put the DTI on no1 inlet, turn the engine to full lift on the inlet an zero the dial,

turn the engine clockwise until the cam is coming onto lift, (use a long bar as you can turn the engine slower and more precisely)

continue until you get to somthing like 5 thou before full lift...

stop and take the reading from the protractor,

then turn until you go past full lift and get to 5 thou after full lift, stop and take the reading from the protractor.

add the two protractor readings together, then divide by two, this is the current timing.

if you use ( or even just refer to) the turbo minis protractor it has where the cam should be reaching full lift marked +/- about 10 degrees so you know oyur in the right ball park.


if your taking a reading and balls it up, just turn the engine back 90 deg and start again.

Ok for the actual cam timing,

put the DTI on no1 inlet, turn the engine to full lift on the inlet an zero the dial,

turn the engine clockwise until the cam is coming onto lift, (use a long bar as you can turn the engine slower and more precisely)

continue until you get to somthing like 5 thou before full lift...

stop and take the reading from the protractor,

then turn until you go past full lift and get to 5 thou after full lift, stop and take the reading from the protractor.

add the two protractor readings together, then divide by two, this is the current timing.

if you use ( or even just refer to) the turbo minis protractor it has where the cam should be reaching full lift marked +/- about 10 degrees so you know oyur in the right ball park.


if your taking a reading and balls it up, just turn the engine back 90 deg and start again.

Basically you do the above because the TDC and max lift areas have a dwell period so are harder to determine accurately by eye


SO you pick a known position on the way up, and this same position on the way down.

ie picture a clock face with no 12 marking.

You have 10 oclock and 2 oclock though which you are measuring with the dial gauge on the way up, then back down again. Note what degrees on the protractor these two occur at and the middle is max lift.

Then you know TDC or max lift is exactly in the middle of this, measured off your protractor.

Whilst you can rotate the engine backwards, when taking measurements ALWAYS rotate in the normal direction of rotation only.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

Okie kokie.... Think I be got it thanks... Right 5 thou before 90deg and 121deg 5 thou after... So 105.5 would you say......... But... I'm hearing time in at 108 and 110........to time in at...
Which one pleeeeeeeaseeeeee

It's a kc500 not strictly an MG n/a....

Ooooh and another quickly....which way is the offset key going in to advance the timing(moving the cam gear clock wise) or to retard anticlockwise.....

This is what Kent Cams say...
http://www.kentcams.com/product-details/17.../500-Mild-Road/
Would it be different for a turbo application...

yep, looks like youve got it, 105.5 sounds right.

110 degrees is correct, but if your using a new chain advance it a degree or so to allow for chain stretch/wear.

All sorted thanks 5deg offset key in...now 110.5 with new chain...thanks again for the support...