Hardkore

i know that there has been some discussion on this before, but it seems like my stage 1+ has lost some kick with the hitachi cp's. engine does seem smoother in general tho. i'm gonna stick my old cp's on and see if there is really any difference. may just be my imagination (but i don't think so).

diagnosticator1

That is, if the ignition timing is correct, and the spark is not weak, there is no way the Hitachi coils will result in less engine output when used as replacements for the OEM coils. Particularly, considering the "smoother overall" engine running qualities often reported. The two effects are not technically compatible. For example, if there was a decrease in spark energy or other property with the Hitachi coils, that was responsible for the alleged loss of engine performance, then, there would not also be an improvement in engine smoothness at the same time.
Some relevant logs of measuring block data would be interesting in comparison.

DenverNoob

revisions, so the spark through the plug is not as strong. many people on BT setups have had to revert back to the OEM stock solution as a result of this....although to the best of my knowledge this was not an issue through the k04 setups.

IIRC the change to higher output coils was to increase efficiency and help get the ULEV rating the b6 1.8t enjoyed.

MikTip

Mines a 2004 as well. Maybe something with the 2004's?<ul><li><a href="https://forums.audiworld.com/a4gen2/msgs/1042958.phtml">https://forums.audiworld.com/a4gen2/msgs/1042958.phtml</a</li></ul>

diagnosticator1

total spark energy, is not consistant with the specifications of the coils published by the manufacturers. Specifically, the Hitachi type coilpack, has a maximum rated secondary output of ~40 KV, compared to the rated secondary output of the pencil style coils, at ~30 KV. And comparing the physical layout and size of the secondary coils used, it should be clearly apparent that the Hitachi style design has a larger magnetic cross section compared to the Bremi pencil style coilpacks. The difference in secondary coil dimensional size and orientation is consistant with the higher secondary coil output capability of the Hitachi designs output specifications.
There are no known references describing the Bremi pencil style coilpack design as having any unique ULEV emissions related functional capability, and the technical reference explaining the design changes made to the prior LEV certified 1.8T, resulting in the ULEV compliant AMB, do not mention any ignition coilpack design or performance related changes required or implemented to achieve ULEV compliance.

DenverNoob

i never really researched the CPs myself as i have nothad a significant enough problem to do so...i just picked that up along the way reading a bit on the forums...

much like the missnomers about other stuff...it appears that is the same.


(in apple speak...im moving that info into my trash...hehe)

Mrkrad

if you don't have hitachi's you can lemmiwinks -3 degrees to get smoother too

diagnosticator1

You are right on about that. ...

Hardkore

gonna try the MikTip route and see what happens.

kevinr

couldn't help myself on that one bud... j/k you're an asset to all the forums you frequent.