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Does detonation affect how fast your car accelerates that much?

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If I remember right I set it at 32 deg total and I know I'm using the right port.

Inititially I had it too far advanced and then re-set it to 32 deg because it was too hard to start.

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put some good octane in there & (1) set your initial where your cam/eng likes it (2) shorten the slots for 36-38 total (vac adv (if used)disconnected) (3) play w the spring combo so you get a fast a curve as possible but staying just under the pinging point as you run it thru the gears @ WOT on your hottest/driest day (4) hookup the vac adv & add as much of it as it will take without pinging (or missing from too much overall timing) @ PART throttle on your hottest driest day. Get each stage near perfect then the next one(& in order) so that nothing is being left on the table.

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The key here is to leave the vacuum advance out of the equation ( disconnected ) until you get the pinging problem sorted out. Then play with the vacuum rate - also ported or manifold source to see what works best.

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put some good octane in there & (1) set your initial where your cam/eng likes it (2) shorten the slots for 36-38 total (vac adv (if used)disconnected) (3) play w the spring combo so you get a fast a curve as possible but staying just under the pinging point as you run it thru the gears @ WOT on your hottest/driest day (4) hookup the vac adv & add as much of it as it will take without pinging (or missing from too much overall timing) @ PART throttle on your hottest driest day. Get each stage near perfect then the next one(& in order) so that nothing is being left on the table.

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But he stated starting problems when he had 36 total? This is usually to short of slots where the
real initial not idle advance is too far ahead for his combo. I like a longer slot to lessen starter kickback and some like shorter slots Oh well tomato tomato?

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But he stated starting problems when he had 36 total?

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What is your comp ?? It does seem odd that with aluminum heads and the 292-509 comp cam with 32 total timing that it would ping ?? Do you where the cam is degreed at ?? Ron

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It's not odd he has vacuum advance pulling in a ton of extra cruise advance that today's gas won't allow and when he gives it more light throttle the cylinder pressure rises causing ping which would not have happened in the days of 98 octane regular and up to 106 high test. You have to tone down (limit) the amount of vacuum advance to stop that ping. Vacuum advance is a crude cruise gas mileage device not suited very well for todays fuels.

Just found this on his engine "I also used Rhoads lifters" will make it work like a small cam at low RPMS I assume

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put some good octane in there & (1) set your initial where your cam/eng likes it (2) shorten the slots for 36-38 total (vac adv (if used)disconnected) (3) play w the spring combo so you get a fast a curve as possible but staying just under the pinging point as you run it thru the gears @ WOT on your hottest/driest day (4) hookup the vac adv & add as much of it as it will take without pinging (or missing from too much overall timing) @ PART throttle on your hottest driest day. Get each stage near perfect then the next one(& in order) so that nothing is being left on the table.

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But he stated starting problems when he had 36 total? This is usually to short of slots where the
real initial not idle advance is too far ahead for his combo. I like a longer slot to lessen starter kickback and some like shorter slots Oh well tomato tomato?

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Yeah what it would do is just crank longer because of the advance. It was really bad once the motor got warmed up and the only way I knew to fix it was back the timing off.

I'll try your suggestions and see if it fixes it. I appreciate all the help as usual.

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What is your comp ?? It does seem odd that with aluminum heads and the 292-509 comp cam with 32 total timing that it would ping ?? Do you where the cam is degreed at ?? Ron

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It's not odd he has vacuum advance pulling in a ton of extra cruise advance that today's gas won't allow and when he gives it more light throttle the cylinder pressure rises causing ping which would not have happened in the days of 98 octane regular and up to 106 high test. You have to tone down (limit) the amount of vacuum advance to stop that ping. Vacuum advance is a crude cruise gas mileage device not suited very well for todays fuels.

Just found this on his engine "I also used Rhoads lifters" will make it work like a small cam at low RPMS I assume

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I'm running a Comp 292/299 .509/.509 cam, Edelbrock 84cc closed chamber heads, Holley 870 street avenger carb, MP ignition (distributer w/chrome box). The block has alsobeen zero decked and I'm running KB flat tops. Can't remember the head gasket thickness, maybe .020"?

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