[Malky]

bigblue, pinging during even mild acceleration is a bit unsual. With the throttle plates only allowing a partial cylinder fill, the effective compression ratio should be low.
I think either you are running very lean like Brad says, or you are getting too much timing too soon.
Check the plugs for white colour and glazing.
As a crude check, you could drive with the choke plate jammed partially closed. If that helps, you may be too lean.
With a dial-back timing light, check how much mechanical advance is coming in by when. 20 deg on top of your initial 10, in by 3000 rpm is typical. Weak springs can cause it to come in too quickly.
Use a hand vacuum pump connected to the can with the timing light to find out how much it advances and when. With your high vacuum, I don't think you want it to start advancing until around 10" Hg.

[bigblue66]

Wow. Thanks for all the incredible information and suggestions. You guys are amazingly knowledgeable. I need to process all this information and work up a plan to diagnose and fix this problem starting with the easiest/cheapest solutions until I get it nailed - and I'm sure I will with help from this forum.
Thanks again.

[johnsma22]

Originally Posted by motor-daddy

What you are experiencing is Detonation. It is caused by the fuel spontaniously combusting creating another flame front after the plug is fired. With more than one flame front, cylinder pressure increases faster, and causes the peak pressure to occur MUCH sooner with respect to crank angle. When this happens, the engine is "fighting' itself and the loser is the head gasket, bearings, pistons, ring lands, resulting in SERIOUS MECHANICAL DAMAGE, AND DEATH!

Detonation causes a very high, very sharp pressure spike in the combustion chamber but it is of a very short duration. If you look at a pressure trace of the combustion chamber process, you would see the normal burn as a normal pressure rise, then all of a sudden you would see a very sharp spike when the detonation occurred. That spike always occurs after the spark plug fires.


The sharp spike in pressure creates a force in the combustion chamber. It causes the structure of the engine to ring, or resonate, much as if it were hit by a hammer. Resonance, which is characteristic of combustion detonation, occurs at about 6400 Hertz. So the pinging you hear is actually the structure of the engine reacting to the pressure spikes. This noise changes only slightly between iron and aluminum.


This noise or vibration is what a knock sensor picks up in a modern computer controlled vehicle. The knock sensors are tuned to 6400 hertz and they will pick up that spark knock. Incidentally, the knocking or pinging sound is not the result of "two flame fronts meeting" as is often stated. Although this clash does generate a spike, the noise you sense comes from the vibration of the engine structure reacting to the pressure spike.


John

[Beebe]

Originally Posted by bigblue66

Wow. Thanks for all the incredible information and suggestions. You guys are amazingly knowledgeable. I need to process all this information and work up a plan to diagnose and fix this problem starting with the easiest/cheapest solutions until I get it nailed - and I'm sure I will with help from this forum.
Thanks again.

http://www.snowperformance.net/default.asp


Can the Boost Cooler® be applied to naturally aspirated and nitrous engines?

1.Naturally aspirated/high compression engines:

In this application, water/methanol injection allows the use of pump fuel in all but the most extreme situations which effects tremendous cost savings as well as horsepower increases due to air density increase and realized timing potential. The system is activated by a throttle switch so that injection takes place only during high engine loads when needed.

2. NOS engines: With NOS, water/methanol injection allows the use of full timing even with large (250HP+) quantities. Injection is controlled by the same means that controls NOS injection.

3. Naturally aspirated/stock compression: With naturally aspirated engines with less than 10:1 compression, water/methanol is used typically in warm climates to get the intake temps back to 60°f. Benefits include: 10-15 HP increases from air density increases and full timing, Increased gas mileage, and carbon free combustion chambers. Activation is by a throttle switch adjusted for onset engine load. With this application, the nozzle is sized so that no more than 10% of total fuel consumption at peak flywheel HP is injected

What are the benefits of Water/Methanol injection?

Boost Cooler® Benefits (Gasoline):

1. Low cost - where else can you get up to 60HP for $299.
2. More power than other means of detonation control.
3. Efficiency - leaner air fuel ratio can be utilized for normal operation.
4. Greatly increases air charge densities for huge horsepower increases

[Formulabruce]

Originally Posted by johnsma22

Your compression ratio is too high, and it is as simple as that. Every time you run that motor you are hammering your rod bearings into oblivion. Either satisfy the octane requirements of the combo you have now by running racing fuel, or change your combo and lower the CR, either by swapping heads or dishing the pistons, etc.

A cranking cylinder pressure of about 160-170 psi is about as high as pump gas will tolerate. It is not really a case of "bad" gas, it is more accurate to say that the modern fuel injected, electronic timing, variable valve timing autos of today do not require the higher octane fuels.

The name "octane" comes from the following fact: When you take crude oil and "crack" it in a refinery, you end up getting hydrocarbon chains of different lengths. These different chain lengths can then be separated from each other and blended to form different fuels. For example, you may have heard of methane, propane and butane. All three of them are hydrocarbons. Methane has just a single carbon atom. Propane has three carbon atoms chained together. Butane has four carbon atoms chained together. Pentane has five, hexane has six, heptane has seven and octane has eight carbon atoms chained together. Octo = eight.

It turns out that heptane handles compression very poorly. Compress it just a little and it ignites spontaneously. Octane handles compression very well -- you can compress it a lot and nothing happens. Eighty-seven-octane gasoline is gasoline that contains 87-percent octane and 13-percent heptane (or some other combination of fuels that has the same performance of the 87/13 combination of octane/heptane). It spontaneously ignites at a given compression level, and can only be used in engines that do not exceed that compression ratio.

John

this guy knows his @#$$%##!!
Ill add, that the 104 bottle you added, adds like .1 to .2 points to total octane so you might have 93.2
adding 3oz of Toulene to a 5 gallon can of 93 will bring you up to 100
BUT watch the heat go way up!!, might need colder plugs.