After having a bit of a missfire when driving down to sign on on sunday morning I decided to pull out the plugs and fit the spare ones I had with me. I was a little suprised to see the colour of them as they had been fitted just before the American Car Worlds nats back in may. the plugs are Autolite 65 and I will have done about 400 miles on them since then they almost looked like they had just came out of the box.
The motor is a 340 and is running MSD ignition timing is at about 36 degrees there was a 750 d/p carb on the top and was jetted slightly rich 76 front and 78 rears. The exhaust tail pipes are black. When the first plug was pulled out we thought their may have been an air leak on that particular pair of runners put all of the plugs were the same. A new set of plugs were fitted, four runs down the strip now on a vac secondary carb (fitted due to air leak appearing saturday morning while in fire-up road when the car suddenly refused to idle in gear )jetted the same and then a 60 mile trip home at a steady 60 miles per hour. This morning I pulled the new plugs out and the are identical to those removed yesterday.Is this a heat range problem or something else. Got to get this right before i try the gas
If you can get a better picture of the plugs from the strap side so that the whole back of the strap and the porceline is visible and also one of down inside (i know damn near impossible) I'll send it to Don, if you can't get one of down inside send me a couple of plugs and i'll post em to him
Also all the specs on the motor and problems you're having and what amount of gas you want to run later
with the pics of the plugs or a couple of plugs and the motor specs he'll be able to tell where the timing is set at without me saying anything and if there's anything wrong what to do to put it right.
there's pictures on our site and Dons as to what angle to take the pics from.
Also take pics of any plugs that look different on the back/top of the strap
in fact pics of all eight would be better
Will
I will get the plugs/pictures to you in a couple of weeks as I am just off on my holidays. The plug reading on you site makes very good reading and is very informative.
Can you pm me your full address and I will pop over and see you when i get back.
Some interesting reading on that site allkiller but no reference to the timing indicator markings which are found on the back of the strap and the mixture indicators which are on the porceline and the WOT mixture ring which is right down at the base of the porceline