Thread: Timing Issue? I wish I could get this thing to stop pinging!

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yep heavy power springs should help in the carb keeping it abit rich on the thinner part of the power rods but small rods may help.yep i know this just a$$ backward today . the plugs are AC RT 44 i think cross over to a R8c champion and is a tapper seat plug 14mm fit SBC tapper seat heads

Originally Posted by pat mccarthy

yep heavy power springs should help in the carb keeping it abit rich on the thinner part of the power rods but small rods may help.yep i know this just a$$ backward today . the plugs are AC RT 44 i think cross over to a R8c champion and is a tapper seat plug 14mm fit SBC tapper seat heads

I totally understand how the step-up springs work and only went up one step, with only 1 step more to go, but like said will probably be going up at least one step richer for power mode, possibly cruise mode too - which would keep the same jet just change the rod. For grins and giggles I will check/set my float levels too.

Since she bogs/hesitates to accelerate a bit a higher RPMs I was thinking about bumping my secondary main jet one size, and possibly my pump nozzle (accel pump rod in highest hole already) but I will only make ONE change at a time and test.

I will try the autolite plugs I have before ANY other changes, if no better, I will go back to the champion plugs I have in now and mod the carb - I will try both sets of plugs with each change to carburetion I make - that way I have an excuse to pull ALL plugs each time

As you found out temp. will cause it to ping. Motor temp. and induction air temp. will affect the pinging also. Under hood temp. If you want to run low octane fuels you have to detune the motor. This is where knowing to DCR is inportant.

Originally Posted by Mikej

As you found out temp. will cause it to ping. Motor temp. and induction air temp. will affect the pinging also. Under hood temp. If you want to run low octane fuels you have to detune the motor. This is where knowing to DCR is inportant.

As we all know temp is a big factor in any machine situation. I was always taught cooler is better, not cold, just cooler rather than hotter. Regarding operating temp for MY car, I am trying to find the balance point between reasonable power, what my cooling system can provide and what my engine likes or runs best at

Ultimately I do want a pump gas driver, but for now while things are new I want a rocket and the extra $0.10 per gallon for premium won't kill me... In your opinion, what would de-tuning the motor look like? Down the line I may want to reintroduce some sanity

Clue me in please, what is DCR?

Mostly I have found that you need to retard the timing. Total mechanical timing. Which if I read yours correctly you are at 24 ( int and mechanical adv.) I'm running about 28. Ideal seems to be 34 to 38 to make power. I run the carb alittle rich. Lower engine temp. Not all good for making power. The other guys on here can explain what the Dynamic Compression Ratio is. But it is what you are after to keep the motor from pinging on lower quality fuels. By the way I'm running 11:1 BBC with iron heads on 91 octane fuel. Pinging is a problem from one tank of gas to the next.

Originally Posted by Mikej

Mostly I have found that you need to retard the timing. Total mechanical timing. Which if I read yours correctly you are at 24 ( int and mechanical adv.) I'm running about 28. Ideal seems to be 34 to 38 to make power. I run the carb alittle rich. Lower engine temp. Not all good for making power. The other guys on here can explain what the Dynamic Compression Ratio is. But it is what you are after to keep the motor from pinging on lower quality fuels. By the way I'm running 11:1 BBC with iron heads on 91 octane fuel. Pinging is a problem from one tank of gas to the next.

Yea, retarding the timing should be my motto these days... Right now I am running around 24* of timing w/o vac adv. I am going to switch weights and springs in my dizzy and blueprint it to get the most out mech adv I can - until a few days ago I ONLY drove it w mech adv and it ran OK, until I changed the plugs... I have a std dist with a pertronix module I could swap back to to test but wanted HEI - always the trouble maker me

In regards to IDEAL timing, 36 seems to be the number to reach, but a total timing of 52* is not out of the question according to Lars Grimsrud, if I read his papers correctly... I would like to get more mech adv and reply on vac less if that is possible - not sure that is even good, just seems so to me

I found a good article on DCR here, time to dig up that cam card

11:1 is really high IMO but not too unusual, I just didn't want the kind of performance/problems associated with high compression engines - as far as the consistency of pump gas goes, that is the one variable we will NEVER have control of so a-tuning-we-will-go all year long

I honestly hope I can run 87 all year long but it looks like not, perhaps 89 in the winter and 91 in the summer cause as we know once the air heats up here in So Cal I get to do this all over again