Rich Mix Compensator --(curious)

old forum · hod rodder Joined: 04 Oct 2001 Posts: 15499

Alright....

To compensate for a slightly rich fuel mix, could you try amping the spark a little to burn the excess fuel entering the cylinder?? I know i could re-jet the carby to suit the engine better...but i want to try some other things...
I was thinking of a BOSCH GT-40 or similar coil and BOSCH super-4 spark plugs...and then find one of those extra spark amping devices...
Just a thought ???

old forum · hod rodder Joined: 04 Oct 2001 Posts: 15499

i think you would be betterof with the right carby or getting it tuned properly

old forum · hod rodder Joined: 04 Oct 2001 Posts: 15499

what fuel are you using?
Try premium unleaded

old forum · hod rodder Joined: 04 Oct 2001 Posts: 15499

I don't think that you quite fully understand exactly what a rich fuel mixture means. Petrol burns at 12:1 (a little over this, I can't remember the exact figure), this means 12 parts air, 1 part fuel. If you have more than 1 part fuel, your car is running rich, if you have less than 1 part fuel, your car is running lean. The result is that the combustion isn't going to happen efficiently (well, at least not as efficiently as it would if it were 12:1). Therefore, putting a bigger coil, or making more spark, isn't going to help, the only thing that will help, is changing the mixtures until they're right.

Paul
Never late in a 308

old forum · hod rodder Joined: 04 Oct 2001 Posts: 15499

The stoichiometric (ideal mixture ratio) is 14.7 parts air to 1 part fuel as engines require much more air than fuel (Fuel/air ratios are usually small numbers eg. 0.068 = one pound of fuel divided by 14.7 pounds of air, that being the atmospheric pressure and all)

Duh!

And yeah, more spark isnt going to do nearly as much good as what more air will if your running ritch

old forum · hod rodder Joined: 04 Oct 2001 Posts: 15499

Yeah 14.7:1, thats the one.

Paul

old forum · hod rodder Joined: 04 Oct 2001 Posts: 15499

Basically no, you cant do what you propose.

Why do you think you are running rich? Have you had an oxygen sensor monitor your exhasut gas? Are you going by the colour of the tailpipe? Are you aware that lead replacement fuel has no lead in it!? Leaded fuel traditionally leaves a greyish tinge to the tailpipe when running good, unleaded is usually black all of the time.

An ignition system burns the mixture. A fatter spark does not necesarrily mean it will burn more fuel. If you have an air/fuel mix in the combustion chamber, and you introduce a small spark, the mix will ignite and a flame front will propogate and combust the majority of the mix.

If you introduce a larger spark, you have more chance of igniting the mix, but it doesnt necesariily mean that you will burn more of the air fuel. You would need multiple sparks at timed intervals to have a greater chance of burning more fuel.

Think of it this way, your kitchen is full of gas. will the house blow up any quicker or more violently if you introduce a spark from a cigarette lighter flint, or if you light a match, than if you introduced the spark from a piezzo igniter (the things in gas heaters and hot water services, they make a small single spark.) The answer is no, either way, the house will blow up all the same.

old forum · hod rodder Joined: 04 Oct 2001 Posts: 15499

ahh, the old clickers.. had many a free video game credits thanks to those back in my day..

old forum · hod rodder Joined: 04 Oct 2001 Posts: 15499

Thats what I said.

Paul
Never late in a 308

old forum · hod rodder Joined: 04 Oct 2001 Posts: 15499

so did i

old forum · hod rodder Joined: 04 Oct 2001 Posts: 15499

so did I.

old forum · hod rodder Joined: 04 Oct 2001 Posts: 15499

I said it first!

old forum · hod rodder Joined: 04 Oct 2001 Posts: 15499

I'm surprised someone even thought of increasing spark energy to correct a rich a/f ratio, instead of trying to fix the problem in the first place. If there even is a problem.

Without some form of measurement, its quite hard to know if an engine is running rich or lean, unless big clouds of black smoke follows the car everywhere.

old forum · hod rodder Joined: 04 Oct 2001 Posts: 15499

what are you talking about? you can tell your car is running rich when it goes through heaps of fuel. Just because its constantly being driven on full throttle doesnt mean shit. So if you want to use less fuel, just run it really really lean. If your putting less fuel into your engine then that’s got to mean your getting better economy. Just run twin msd ignition modules on stock engine so you get a really massive spark to burn every bit of fuel that’s there.

old forum · hod rodder Joined: 04 Oct 2001 Posts: 15499

Doesn't it really matter who did or didn't say they were going to blow up his house? That is what we are talking about here right? or did I miss the point, again.