After again raising the ante in ignition systems, it's again apparent there is no such thing as too much ignition.

From another list, where I posted the results:


While I just got my latest experiment running, it looks like DIS, does in fact leave something on the table.....

In quick reveiw for those just tuning in:
I updated my car to use the later Quick Start Igntion system, which uses the Type II coils.
Then I installed an ACCEL 300 CD module on each of the coils.
When I added the CD modules, I had to add some more fuel to maintain the same AFR's.

Today, I finished installing 6 of the GM *E* (mid 90's V8 TBI) series of ignition coils, with a ACCEL 300 module running each coil. For the moment, the coils are being fired in pairs.. The *gain* is that there is no/ or potential wasted spark energy.

With the additon of the Quick start, starting has always been rather quick, and now it's even quicker. It's almost hard to believe how short the cranking period is. With temps in the mid 50's, and having rained this morning, the roads are way to slick to do any serious high throttle opening testing, but it's obvious things are better. My tune has always been a little lean down low, in an effort to get the best MPG, so to *stage* I always had to go to a *fast idle* to leave quickly. Now, I can just crack the gas from idle, and the car pulls away crisply, and without hesitation.

*Response* wise, this set-up, slightly beats the CNP setup I ran (that used the late GM CNP individual coils).

I still have to cut up some plugs, and play with the timing to optimize things, but so far, it seems to be a very worthwhile modification. Trouble is the weather's due to turn cold again......

As far as going to the 6 coils. I bought the coils from a local junkyard, for $30. The CD modules were off of eBay, and ran from $50 to $75. Then there was the cost of new plug wires. I also had a bracket welded up, to hold the coils, but a friend did that for nada. I'd guess I have $400 in it all together.

You can use any module for triggering the CDs, they don't draw much current to trigger (ie ~250 milliampes in the case of the ACCELs).

Results, include dropping the EGTs ~100 dF in cruise, and about 200dF in heavy loads.... I'm at a lose to explain why, but the proof is that it does.

 

How did you address spark timing though the calibration?


Maybe because you can now get away with more timing than before, and didn't find the "sweet spot" yet? Or just a more complete burn?

 

So far, I haven't changed the timing or fueling.

Hopefully I'll be able to run less timing, and run larger plug gaps. At the boost levels I run, the *norm* is closing the gaps down to .025". FWIW, at slightly lower levels, running the GM CNP coils, I was able to cut off the side electrodes, and run a .100" gap, at a signifigantly reduced amount of timing.