Black 3.3 pinging

[bigal]

Does anyone know why the black motors are so prone to pinging. Is it the EST computer, the carby running rich and carboning up the cylinder head, the shape of the combustion chamber? I wouldn't think it was because of too high a compression.

I have disconnected the EST, put in elect dizzy, put a kit thru the carby and decarboned the head. I've even smoothed out the combustion chamber, getting rid of the ridge. It has helped but still pings occasionally.

A mechanic told me that he rang GMH once and they told him to use TWO head gaskets.

I have another engine that I am putting together, so any help would be appreciated before I get too far.

Cheers, Big Al

[Spike79]

This might be a bit too obvious but what petrol are you using?

Have you got a high enough octane rating? I think it should be 97octane, unfortunately this means using PULP or putting an octane booster in the tank.

[vkberlina]

This might be a bit too obvious but what petrol are you using?

Have you got a high enough octane rating? I think it should be 97octane, unfortunately this means using PULP or putting an octane booster in the tank.

Or just buying 98 octane fuel at the bowser either Optimax, Ultimate 98, Vortex or Synergy 8000 (I think its 8000)

[sed8]

combination of low octane fuel and maybe to much timing

[darkmoon]

I have an EFI 202 that pings its nut out on ULP. I run PULP and use Nulon Octane Boost. An airforce mechanic put me onto it and it doesn't cost heaps. It gives you an octane boost, injector/carb cleaner and upper cylinder lube (which the older leaded motors need). Thats an easy and cheap fix, try it and see how you go.
Kain

[SUSPECT]

yea i did the same thing as darkmoon on my vk worked a treat i stand by nulon products

[spd_dmn]

I have an EFI 202 that pings its nut out on ULP. I run PULP and use Nulon Octane Boost. An airforce mechanic put me onto it and it doesn't cost heaps. It gives you an octane boost, injector/carb cleaner and upper cylinder lube (which the older leaded motors need). Thats an easy and cheap fix, try it and see how you go.
Kain

Sounds like a good thing. Do you still need to use a valve saver? How much does it cost?

[bigal]

Thanx guys, Octane booster did the trick. But what I really wanted to know is why the black motors are more inclined to ping than say the red motors. Black motor comp. ratio 8.8-1, red motor 9.2-1 so you would think that the red motors would ping more?? Is it because the red heads have a different shape, or is it the computer in the VKs or something else?
Cheers, Big Al