Either will be fine. So cheaper is better. In fact,any 4 mitsi 4 cyl ignitor will work as we dont need to use a Tacho output.

I used a secondhand ignitor- not much ever goes wrong with them- so you could go second hand.

Yeah- the coils are so cheap, but work so well!

 

Sounds good... Maybe I'll see if the local junkyard has one... Now I just need to get the head back, and decide if I'm going to do drop in pistons/rods or not.

 

How would you guys rank this setup to the setup offered by Road Race Engineering. I kind of like the idea that it would appear more "stock" under the hood with the bolt in coils. How would this rank in terms of performance?

 

Guess it would come down to specs and price... and what you actually mean by "better". Hell, you can do the one in this thread for well under $200... and much lower depending on what you have access to. I mean I found the coils brand new at AutoZone for $24.99 a piece for Christ's sake.

Maybe monsta can add actual specs for the OE coils as I don't know their actual output.

In the end though, I'm a "bang for the buck"/do it yourself *****, and this is the shizz in that regard.

 

Can't sneak much past you can they . It's RHD .

Did you happen to see he resides in New Zealand????

 

The system you show is a CDI system conversion, compared to the stock wasted spark system.

The CDI systems that alot of the vendors are selling can run much higher HP levels than any wasted spark system.

The wasted spark COP systems that some vendors sell run out of steam @ 600whp just like the system I have put in my car.


Vendor Wasted-Spark systems
Pros:
Easy to install-(idiot proof)
Run well
Very tidy

Cons:
Relatively expensive
Limited in max power ability

Vendor CDI system
Pros:
Run well
Very well designed
Very Tidy
Exceptional power handling

Cons:
Have to sell your children to afford to pay for it
Can be a little harder to install because of extra ignition amplifier box


DIY/DSM wasted-spark
Pros:
Run well
Cheap

Cons:
Limited Max horsepower
Relatively difficult to install
Adds spark plugs leads



I was going to buy a Vendors Wasted-spark COP system (AMS) but as Im pretty clued up and a tight b@stard, I tried the DIY instaed, with good results.

So-
If youre a "Bolt-on" guy and like an easy install- get a vendor Wasted-spark COP

If youve got a turbo that sucks children off the sidewalk when you drive past- get a vendor CDI COP

If you like getting your hands dirty try my solution

 

Interesting looking coils. Do you have the actual primary and secondary resistance and inductance specs for them?

What sort of current were you getting during dwell at idle, and high RPM? Was it measured on car with the DSM ignitor?

There were a few issues I ran into when trying to find better than stock coils that were a good match for the built in limits of the DSM ignitor current capability, and the stock ECU dwell times. So I am curious how these rank in terms of all that stuff.

Did you paint the bracket the ignitor is mounted on? The bottom of the ignitor is a heatsink, and the ignitors have been known to fail when not properly heatsinked, although it isn't very common. They are pretty robust and you did get them to a cooler spot, but I'd put them directly on an aluminum bracket for the extra heat sinking, just to be safe.

 

I'd like to find specs on these too... however, I'm interested enough, and it is cheap enough that I'll probably give it a go regardless. The community REALLY, REALLY needs something like this, as EVERYTHING else is so damn expensive!

So I hope it really does deliver "more".

 

what do you guys think about the AEM Pencil Coils coupled with their Twin Fire Amplifier vs. the High end Ingitions out there?

 

Off topic. I'll leave it, but it needs to be answered/replied to in another thread or via PM's

 

The primary resistance is the same as a DSM coil (0.8ohms) and the primary coil inductance is 10% higher than dsm. The secondary resistance is 10Kohms. Your choice of ignition wires can greatly affect the actual secondary circuit resistance.

Dwell (charge time) is listed at <2.3ms. This is plenty fast enough to charge within the Ignitors current limit for the primary coil.

I have not tested the ACTUAL dwell time while running on my car.


I too was worried about the current limitations of the DSM ignitor. I needed to find a coil which didnt draw too much current that the ignitor couldnt handle, and still had plenty of time to charge within the ecus allowed dwell time.
I then had to find a coil that had excellent break voltage to be able to handle jumping the spark through the quite high resistance of a high powered combustion chamber.



Hope this helps guys

Aaron

 

Thanks Aaron.

Now you have me wondering about what wires to look for...

 

Interesting...always nice to have options.

 

you my friend just got put in my signature!

 

Are you sure the 0.8 ohms is the same as the DSM? I don't have my notes handy, but I recall it being slightly lower than that.

If the resistance is the same, and the coil primary inductance is slightly higher, it is PROBABLY going to result in taking a little longer time to get to the same current levels during dwell. If the resistance is higher, it would take even longer. The coil is storing more energy, but it takes longer to do it. And if it doesn't get to as high of a current, what you have to worry about is at high RPM. As the dwell time falls off, the current is going to fall off quicker. This is going to affect the voltage available to the plugs to start the spark, and could result in a coil that is great, until you get to high RPMs

The coil secondary resistance isn't a huge issue. Knowing secondary inductance is more important. That tells you the turns ratio of the coil. Did you get that info?

The resistance of the plug wires isn't really that important. You can potentially lose a few % here and there with them, but the IR losses through the plug wires are not anywhere near as important as getting the right coil.

The breakdown voltage isn't as big an issue as matching all the other specs. Most decent coils nowadays have that covered.

What does the 2.3ms dwell time mean, how do they spec that charge time? What current level do you get to in 2.3mS? What energy storage do you get in that period?

The energy is a function of the square of the current, so increasing current is more important than increasing inductance to get more energy. And usually adjusting one, adjusts the other in the opposite direction.

ETA:

With keeping the same resistance and more inductance, I really think this is going backwards from the direction you need to go with the coils. But testing will tell.