pinging and knocking

[paul guy]

I have done nearly 4000 miles in my 30 mod Town Sedan on a rebuilt motor and it goes great I am really impressed but I cant seem to stop the pinging ang knocking when I want more power like going up a steep hill and I always have to back of. Any suggestions I run a 6.1 head, electronic ignition, weber carby, touring cam, lightened flywheel, slipper bearings. I use high octane fuel I have it retarded about 8 degrees. The motor does not run hot any ideas thanks paul from down under

[H. L. Chauvin]

Engine pinging while going up a steep hill is usually a result of advanced timing.

Retarded 8 degrees -- retarded 8 degrees from what?

It would help to know how many degrees are you before top dead center, (BTDC) when climbing a hill.

Merry Christmas

[paul guy]

thanks for your advice. I retarded the timing 8 degrees from TDC at idle approx 450 rpm. Because I have fitted a electronic dizzy I dont really know how advanced the timing is when it starts to ping and knock I hope this helps thanks paul

[Patrick L.]

It sounds like you have and are using a timing light. It would be nice to see how much and fast the advance you are getting. It sounds as if you're getting too much advance too quickly. What type of advance system does this distributor use? If it uses springs and weights, then it can be adjusted to limit and slow the amount of advance by changing to heavier springs/weights.

[Marco Tahtaras]

Do you have anyone around with a cheap tach/dwell tester? You need to test and log the timing at various engine speeds to determine the advance curve (or have the distributor tested). It may not be suitable for your application. In the meantime it sounds like you need to retard the timing a bit.

[paul guy]

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Thanks for your ideas guys it is an fs dizzy I will check it out more and let you know thanks Paul from down under

[Jim/GA]

If this is the FS distributor with the weights and auto advance, they can get you springs/weights for the 6.0 head and you will not have a problem. We initially thought you were advancing with spark lever on the column. You really want the initial timing to be close to zero at TDC, not 8 degrees retarded. FSI can fix you up.

[paul guy]

Thanks Jim I will contact FSI they have been very helpful in the past. Regards Paul from down under

[Marco Tahtaras]

Originally Posted by Jim/TX

If this is the FS distributor with the weights and auto advance, they can get you springs/weights for the 6.0 head and you will not have a problem. We initially thought you were advancing with spark lever on the column. You really want the initial timing to be close to zero at TDC, not 8 degrees retarded. FSI can fix you up.

Regardless of what I'm told I'm purchasing I would test and log the advance curve. Also, If the centrifugal advance is designed to be timed at TDC at idle then it will have insufficient advance through the low and mid ranges.

[bill44]

I had the same problem with a 5.5 head. I sent the unit back to FS and had them reduce the advance to 22*. That seems to have solved the problem. I won't know for sure until Spring.

[paul guy]

Thanks every one for your help, I think I have solved the problem after some advise from fs ignitions I checked TDC with number 1 spark plug removed and found that the indentation in my fibre timing gear does not exactly correspond with number 1 piston being TDC regards paul from down under