Ignition Thoughts/Ideas/Recommendations

[NoDOHC]

Originally Posted by TitaniumTT

The LS2 coils have been known to auto-ignite and pop engines when cranking.

Interesting, I wish that I had heard that previously. I have had no issues to date, but I have carefully isolated the ignition circuit (both hot and signal ground go all the way back to the battery, while the coil secondary ground connection is made on the rotor housing). I wonder if the individual setting it up installed sufficient bypass capacitance...

It requires less than 1 mA to the igniter to fire the coil, so a little noise could definitely cause that.

How do you pop an engine by auto-igniting while cranking?

Originally Posted by TitaniumTT

I still plan on testing the LS2 and LS1 coils against my Bosch coils. I suspect they'll loose a little power compared to the Bosch and the QuickSilver coils that Vex mentioned.

I wish I had talked to you before I made my decision (although I still would probably have chosen the inexpensive route). It appears that those I spoke to about LS2 coils had a much higher opinion of them than you do.

Out of curiosity, why do you think that they will make less power? The LS2 coils spec out well (not that specs mean much, but you have to go by something).

Anyway, If you want a set to test, I may be able to get you one, but I will have to talk to my buddy (who bought the other 4) as to when he will need his.

[TitaniumTT]

Originally Posted by NoDOHC

Interesting, I wish that I had heard that previously. I have had no issues to date, but I have carefully isolated the ignition circuit (both hot and signal ground go all the way back to the battery, while the coil secondary ground connection is made on the rotor housing). I wonder if the individual setting it up installed sufficient bypass capacitance...

It requires less than 1 mA to the igniter to fire the coil, so a little noise could definitely cause that.

How do you pop an engine by auto-igniting while cranking?

It's happening to some RX8 guys that can't adjust the dwell time.

Originally Posted by NoDOHC

I wish I had talked to you before I made my decision (although I still would probably have chosen the inexpensive route). It appears that those I spoke to about LS2 coils had a much higher opinion of them than you do.

It's a GM product, I'm obliged to have a poor opinion of them

Originally Posted by NoDOHC

Out of curiosity, why do you think that they will make less power? The LS2 coils spec out well (not that specs mean much, but you have to go by something).

LS1
The Quicksilvers are a stout coil. They light off some nasty mixes. I want to get Peters CDI kit and put them against the best of the inductives in a non water injected, lower RPM envirornment

Anyway, If you want a set to test, I may be able to get you one, but I will have to talk to my buddy (who bought the other 4) as to when he will need his.[/QUOTE]

[RICE RACING]

Screw using the coil as inductor, it works heaps better as a step up transformer (CD) system.

There are stacks of DIY CD systems (youtube it) you'll see tons of video's of cunts who have made there own systems. Seems allot less trouble than frying coils using excessive charge times in the hope of initiating a suitable spark.

No doubt in my mind that CD gives a far better spark after I personally documented the on road performance improvement that also backed up the increased power recording too.

This week I will get around to scanning that Mazda article on CD ignitions V's inductive.

[TitaniumTT]

Please do man, I would love to read it. Especially as it's tested on a much lower hp, lower rpm, more normal street type engine. Like I said to ya earlier, in my mind it'll make a huge difference on an engine like yours - huge combustion pressure, water injected, etc etc, but an n/a, stock port, 7k redline engine.... not so much.... but that's me

[RICE RACING]

Originally Posted by TitaniumTT

Please do man, I would love to read it. Especially as it's tested on a much lower hp, lower rpm, more normal street type engine. Like I said to ya earlier, in my mind it'll make a huge difference on an engine like yours - huge combustion pressure, water injected, etc etc, but an n/a, stock port, 7k redline engine.... not so much.... but that's me

Here you go Inductive lover

Page 1


Page 2

[TitaniumTT]

Thanks man! I shall study tonight when I get a chance

[dudemaaan]

To the OP, so far the talk has been on getting a stronger ignition for better spark output. Just curious if you have gone to the basics and tried spark plugs that required less current? Iridium plugs have a smaller electrode and conduct electricity better then most other plug materials which would result in a hotter spark with the same voltage.

I know when I switched to iridiums the difference was night and day, not only in how the car ran, but also in the life of the plugs. I ran through b10egv plugs every couple of months, and have been running the same set of iridiums for 2 years now. They were expensive initially, but have more then payed for themselves in the 2 years running them.

I don't have a great ignition system, just a twin power, 10mm wires, stock coils, and iridium plugs, but I have never had breakup and it lights my 750cc/min water injected rotary running 26 psi and 10.9:1 afr's just fine. Maybe I have some power left on the table, but that's okay the car is dangerous enough.

[vex]

Originally Posted by RICE RACING

Here you go Inductive lover

Originally Posted by TitaniumTT

Thanks man! I shall study tonight when I get a chance

I have that article too as well as a few others. "Recent Technology Development of High-Powered Rotary Engine at Mazda." SAE 841017, 1984. Do you by chance of 900036, 912479, 940309, and 950454? I couldn't find those when I looked.

I'm not sure about everyone else, but I don't know if I could justify the increase in price from an HEI to a CDI for the 7.88 HP increase at 8000 RPM. For a race, shop, or similar type setup of course, but looking strictly at the numbers; that's a lot of money for a small amount of HP.

[RICE RACING]

Originally Posted by dudemaaan

To the OP, so far the talk has been on getting a stronger ignition for better spark output. Just curious if you have gone to the basics and tried spark plugs that required less current? Iridium plugs have a smaller electrode and conduct electricity better then most other plug materials which would result in a hotter spark with the same voltage.

I know when I switched to iridiums the difference was night and day, not only in how the car ran, but also in the life of the plugs. I ran through b10egv plugs every couple of months, and have been running the same set of iridiums for 2 years now. They were expensive initially, but have more then payed for themselves in the 2 years running them.

I don't have a great ignition system, just a twin power, 10mm wires, stock coils, and iridium plugs, but I have never had breakup and it lights my 750cc/min water injected rotary running 26 psi and 10.9:1 afr's just fine. Maybe I have some power left on the table, but that's okay the car is dangerous enough.

^ Have you ever actually tested your car? be it to confirm the power or the speed of the vehicle with something like a VBOX instrument?

I'd like to see some numbers from it so we can compare it.

[RICE RACING]

Originally Posted by vex

I have that article too as well as a few others. "Recent Technology Development of High-Powered Rotary Engine at Mazda." SAE 841017, 1984. Do you by chance of 900036, 912479, 940309, and 950454? I couldn't find those when I looked.

I'm not sure about everyone else, but I don't know if I could justify the increase in price from an HEI to a CDI for the 7.88 HP increase at 8000 RPM. For a race, shop, or similar type setup of course, but looking strictly at the numbers; that's a lot of money for a small amount of HP.

Power is just one side.

The others are (and these are tangible effects) is firing of the plug when it is fouled (allows you to use racing heat range at all times), Ability to fire all kinds of mixtures (heavy fuel and lean fuel). Better fuel economy (I have noticed this on CD Ignition).

Just some more things to think about. Though it can be expensive, especially if you go full anal like I did

[vex]

Originally Posted by RICE RACING

Power is just one side.

The others are (and these are tangible effects) is firing of the plug when it is fouled (allows you to use racing heat range at all times), Ability to fire all kinds of mixtures (heavy fuel and lean fuel). Better fuel economy (I have noticed this on CD Ignition).

Just some more things to think about. Though it can be expensive, especially if you go full anal like I did

I understand what you're saying and would like to know a little bit more. When you're talking about heavy fuel and lean fuel mixture what numbers are we talking about? The coils I linked seem to be able to handle extremely rich fuel mixtures (I'm not sure about lean as TTT didn't really tell me if he tested 'em there) without issue.

When the plug is fouled do you see a decrease in performance? I would think that continually firing when the plug is carbon fouled would just result in additional fouling becoming present on the plug leading to the same effect as the HEI just later on in the plug lifetime.

MPG's; I would think would be more indicative of driving style rather than spark energy, but if you have data to support it than so be it.

[My5ABaby]

So...

Budget: LS1 or LS2
Midrange: 034
$$$: CDI

?

Originally Posted by RICE RACING

Though it can be painful, especially if you go full anal like I did

Fixed.

[RICE RACING]

You know when you petrol foul a plug, the car will misfire is bad enough at light cruise, your EGT will go up and it mostly happens on the trailing spark plug as the fuel easily gets trapped in behind the blind plug hole.

it's a catch 22 you run the right heat range for full power and if you cruise it too much or have not enough load you will foul a plug, this is mostly the reason the CD was instituted @ mazda for competition engines, anyone running a Peripheral Port will tell you that who has lived with one as a daily (I did for about 7 years) but back then was ghetto spec and could not afford SFA let alone a don mega CD set up.

On a lean fuel setting 15:1 or weaker you will see the CD will fire better and more consistently compared to Inductive, all round I say my experience is its a better system of ignition, but again like all good things it costs ca$h.

[TitaniumTT]

Originally Posted by RICE RACING

Power is just one side.

The others are (and these are tangible effects) is firing of the plug when it is fouled (allows you to use racing heat range at all times), Ability to fire all kinds of mixtures (heavy fuel and lean fuel). Better fuel economy (I have noticed this on CD Ignition).

Just some more things to think about. Though it can be expensive, especially if you go full anal like I did

Soooooo, what are you saying?

Originally Posted by My5ABaby

So...

Budget: LS1 or LS2
Midrange: 034
$$$: CDI

Budget = stock. LS1 coils are crap.. I wet fouled one after 15 minutes of idling after a rebuild. Haven't had a chance to test the LS2's yet. Don't think they'll compare to the QuickSilver coils though.

Just to clarify, the "034" coils aren't 034 coils. They're QuickSilver coils. QuickSilver being a division of Mercury Marine. The coils come off of their 150hp+ OptiMax outboards.. iirc....

Originally Posted by RICE RACING

You know when you petrol foul a plug, the car will misfire is bad enough at light cruise, your EGT will go up and it mostly happens on the trailing spark plug as the fuel easily gets trapped in behind the blind plug hole.

it's a catch 22 you run the right heat range for full power and if you cruise it too much or have not enough load you will foul a plug, this is mostly the reason the CD was instituted @ mazda for competition engines, anyone running a Peripheral Port will tell you that who has lived with one as a daily (I did for about 7 years) but back then was ghetto spec and could not afford SFA let alone a don mega CD set up.

On a lean fuel setting 15:1 or weaker you will see the CD will fire better and more consistently compared to Inductive, all round I say my experience is its a better system of ignition, but again like all good things it costs ca$h.

Good info here...

[vex]

Originally Posted by vex

I have that article too as well as a few others. "Recent Technology Development of High-Powered Rotary Engine at Mazda." SAE 841017, 1984. Do you by chance have 900036, 912479, 940309, and 950454? I couldn't find those when I looked.

I'm not sure about everyone else, but I don't know if I could justify the increase in price from an HEI to a CDI for the 7.88 HP increase at 8000 RPM. For a race, shop, or similar type setup of course, but looking strictly at the numbers; that's a lot of money for a small amount of HP.

Fixed