maclu88

hi guys. not long ago i had a new clutch installed, and not long before that i had a complete tune. new leads, plugs, rotor, points etc the lot. dont get me wrong, my bug runs great, except for when trying to accelerate up slight hills on the freeway and such. especially after i have been driving for a while and the motor is hot, any acceleration to go faster than 100km/h or to try and maintain that speed up the slightest of hills, the motor pings and no speed increase.. is this normal? please help. i have a 1971 superbeetle.

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MY72BUG

Hi maclu.  One point of departure and an easy one at that, is the octane rating of your gasoline.  Don't ask me how it works other than higher octane gas takes away the pre-ignition pinging which is so characteristic of engines working at high temperatures under loads.  The inside of your cylinder stays so hot that it cooks off the fuel before the spark arrives.  High octane is immune to this.  VW books call for 91 Octane.  Regular fuel around here is 87. I have never experienced pre-ignition but this is the path I would follow before I did anything to an engine which already runs well under other conditions.  On the subject of fuel, a recent newspaper article spoke highly of the new Shell fuels which work to clean deposits off of the valves in your engine.  Heavy deposits of carbon can be the other culprit when engines ping.  Give this a try and let us know if it makes a difference.  Dan (MY72BUG) in Goderich, Ont.

I'd rather have a partial bottle in front of me than a partial frontal lobotomy.
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bumblebee73
i would agree , if the engine is origional , it was designed to run on leaded gas . either raise the octane level , or try a lead subitute
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