[FoxHoss]

thats awesome right there. the proof is in the puding!

[zak2006]

Trick Tuners: Not that it matters but you cant assume 132psi in the CC. If you include thermochemisty, crank angle (spark duration), fuel calculations you get about approx. 2750kpa or 400psi for NA gasoline engines per cylinder. *#'s from a GM 2.4L 4cyl engine (have other data to prove in mutliple matlab codes i personally wrote)

CliffyK: MME huh? I am finishing up my BSME this semester and start my MME in Jan. I am down in Daytona at Riddle. Eco Eagles The Premier EcoCar The NeXt Challenge Team this is the current project I am working on, thought this might be interesting to you.

[cliffyk]

Originally Posted by zak2006 Trick Tuners: Not that it matters but you cant assume 132psi in the CC. If you include thermochemisty, crank angle (spark duration), fuel calculations you get about approx. 2750kpa or 400psi for NA gasoline engines per cylinder. *#'s from a GM 2.4L 4cyl engine (have other data to prove in mutliple matlab codes i personally wrote) CliffyK: MME huh? I am finishing up my BSME this semester and start my MME in Jan. I am down in Daytona at Riddle. Eco Eagles The Premier EcoCar The NeXt Challenge Team this is the current project I am working on, thought this might be interesting to you.

Way cool, I take it then you have heard of John Heywood, and Charles Taylor--I had the distinct honor of studying under Heywood at MIT.

Maybe we can get together and toss a few back sometime...

[zak2006]

I have heard of Heywood and that must have been a great experience. I wish i had an opportunity like that, I have been working my butt off to get my self in a position like that but i am not giving up hope.

and we can definitely get together some time. i know there is an meet at brothers performance in Deland at the begining of december that me and another member are going to check out. i will pm you the date when i get a chance to look up the date

[Trick Tuners]

Originally Posted by zak2006 Trick Tuners: Not that it matters but you cant assume 132psi in the CC. If you include thermochemisty, crank angle (spark duration), fuel calculations you get about approx. 2750kpa or 400psi for NA gasoline engines per cylinder. *#'s from a GM 2.4L 4cyl engine (have other data to prove in mutliple matlab codes i personally wrote)

I'm talking about before the spark fires, but i still may be wrong

[zak2006]

In case your number makes sense and that would essentially be the starting condition that the spark would overcome. The spark would haven to be able to be retained (spark duration) with the pressures I stated. Obviously this is happens in fractions of fractions of seconds (micro I believe, if not less). If the spark cannot meet the initial conditions you stated it definitely can't withstand the following conditions. I understand what you were getting at now, had a long day yesterday in the lab so brain was a little off. Didn't mean to bash your post!

[Trick Tuners]

No worries. Its always good scientific practice to question others and bounce ideas back and forth.

[akvanden]

I digress...

j/k I wish I knew what you guys were talking about... congrats though on the ingenuity... always enjoy reading about homemade ways of doing things.

[cliffyk]

I don't know if anyone is interested, however I was so into playing with the big sparks when I first got this together that I completely forgot about capturing some primary VT traces--here are waveforms for the firing of a Champion platinum plug gapped at 0.054", and the Ampro adjustable tester set to a 15mm gap:

Champion @ 0.054"


This is a pretty classic looking plug firing event, you can see the ionisation of the gap (the big leading spike) and then the ringing (dissipation of remaining power) after the short duration spark (because it's firing in air at STP).

Ampro @ 15mm:


Here you can see the "big dump", the COP's entire potential is being dumped in one big 15mm spark. The ionisation and spark event voltages are the same, there is a very audible "snap" accompanying this lightening type event.

The total delivered power of the two discharges is clear in the pulse widths, this is why when testing the COP's maximum output using this device you need to be cautious so as to not burn out the COP.

[stangladesh]

What is it about the Accel COP's that cause them to not perform at level of the Ford product? I thought Weapon X were superior to the Ford product.

[cliffyk]

Originally Posted by stangladesh What is it about the Accel COP's that cause them to not perform at level of the Ford product? I thought Weapon X were superior to the Ford product.

News Flash!!!

People that sell things often exaggerate their product's performance characteristics...

In the case of the Accel COPs I will point out that I had run them 20k miles before three failed (2 in the same week, one began misfiring the next week), so those that remain may have been similarly degraded--I never tested them when they were new.

The manner in which higher output is attained in the OEM type package is to use fewer turns of wire on the primary side of the coil, and/or more turns on the secondary. Both of these increase the potential output, however they both also increase the amount power (heat) dissipated. Heat is the mortal enemy of nearly anything electrical.

I had high hopes for the WeaponX COPs because of their new design, using an axial wound coil that actually sticks down into the plug well. However heat also turned out to be their downfall. I believe this was because what is exposed of the WX COP body is insufficient to dissipate the heat they generated AND the heat they absorbed from being down in the plug well.

Perhaps Ford's engineers did know what they were doing, both with the internal design of the coil and with making it so that the body of the coil is mounted up above the head?

[Trick Tuners]

Originally Posted by cliffyk I had the distinct honor of studying under Heywood at MIT.

Damn cool! I missed that on the first go around. I still want to read his book, but $150+ is pretty steep! Good job on the testing, and cool traces If you don't mind, i'd love to have this tech on my forums. I could copy pastes (and credit you), or you could register and post it yourself, (if thats cool with you), or you could say no.
http://www.tricktuners.com/forums/forumdisplay.php?f=10
Did you test the output of the weapon x coils? I've heard that they are the same as some coils used on some street bike, but that is just a rumor.

[cliffyk]

Originally Posted by Trick Tuners Damn cool! I missed that on the first go around. I still want to read his book, but $150+ is pretty steep! Good job on the testing, and cool traces If you don't mind, i'd love to have this tech on my forums. I could copy pastes (and credit you), or you could register and post it yourself, (if thats cool with you), or you could say no. General Tuning Related Information - Trick Tuners Forums Did you test the output of the weapon x coils? I've heard that they are the same as some coils used on some street bike, but that is just a rumor.

I have no problem with your copying my posts, however I have retrieved another DSO I had let a a local lab borrow, and will be doing so additional testing tomorrow. This other scope has a 10V/division scale which with a 10X probe should allow me to capture the entire range of the "big gap" primary discharge (I think it was being folded back on the 5V/div and 10X probe using the portable scope).

If you like I would be pleased to join your forum and post a clean and more organised version of the test apparatus and data.