On my crank pulley there are 3 marks. 1 of the marks is lined up with the seam in the crankcase in the photo, the other 2 are further to the right and are close together.

Would I be right in assuming that the mark on the left is TDC and the 2 other marks are 5 degBTDC and 7.5 degBTDC?

If that is correct then 30 degBTDC would be 44.5mm further to the right of the TDC mark (for my diameter pulley).

If the mark on the left IS NOT TDC, then I am lost.

As you can tell from the surface rust she hasn't run much for a while, but when it does it runs rough and backfires, since the compu-fire was put in.

Oohh .....

and I just noticed the dot on the right crankcase half

Steve,
I think you are right with the timing marks.

i think theyre tdc 7.5' and 10' backfires and carrying on sounds like plug leads to me. if you had these off, check them 3 times,(youll be convinced ya got em right!) then go away for ten minutes come back and put them how they should be!...thats what seems to happen to me. cheers

Hi

The best way to tell is to fit a known pulley to your car and see where it lines up. Try to get a degreed pulley or a later bug one. The later bug ones had a mark for TDC that looked like an angle grinder mark and to the right of the TDC mark was a 7.5 mark.

Steve

yep the first mark is TDC the second is 7.5 and the 3rd is 10 try running your engine and advance the timing till the engine is running at its fastest. and then take it for a drive up a steep hill and if it pings retard it slightly. and then take it for another drive. if it doesnt ping then leave it.

Well, it's fixed.

As it turns out, #3 lead was off th plug. I forgot I had removed it while trying to work out runner lengths for the EFI conversion (but that's another story!). Anyway, thanks Dumone, you were right - "check those plug leads first!" :cussing

Then hooked the timing light up, got the kids to try and hold the revs @ 3000 while I fiddled at the rear. Timing was out, but not any longer. Whoohoo.

Thanks guys.

Like the 3 on the pulley in the photo above

Steve

The pully marks are a great guide to use... and set up. Once the engine is running make sure its not pinging. If it is then you might have to vary the timming to suit this particular engine, and fuel we are now using.
Each engine set up can be slightly different with many variables to consider.

Thanks Dave,

I have ULP in it ATM, and "The Man" says that's fine, but I'll more than likely run BP Ultimate when she'sback on the road.

if u run BP ultimate you will find you can advance your timing considerably

Steve ive been using Optimax for the past 3 years no problems at all...
so the BP would be good as well.

Hi

If you think you can set your timming by listening for pinking you must have very good hearing, you will not hear the pinking sound over the mechanical noise of the motor, if you can hear pinking your way overadvanced. Over advanced timing is like tightening a bolt, strip the thread and back it off a turn.

The TDC mark on the late pulleys is on the outer rim of the pulley, most rear facing. It looks like someone nicke the pulley with a grinder.

The timing should 32 degress total for a stocker and 30 for a modified motor, measure the circumference of the pulley and you can work out the total timing mark on your pulley.

Steve

I used this formula

arc distance = 2(pi)(r)a/360

= 2(pi) 85 x 30/360

= 44.5mm

[Edited on 19-1-2005 by 56astro]

im not saying you can hear the pinging when u are changeing the timing but when u take it for a drive u can hear it. ive found that i have to have my timing more advance because im running it on 98 octane and 7.5BTDC for a 1600 just doesnt cut it. im running about 13BTDC. and the easiest way to find a good mark is to advance ti till the engine runs its fastest and then back it off a little and take it for a drive and fine tune.

yes pinging when test driving, trial and error