Jon, the point you are overlooking is that you are thinking of the spark you have seen at low revs. As you say the standard coil produces a perfectly adequate firelighter. However, at 5000 rpm there roughly a tenth of the time between discharges for the coil to build a nice stable field. Up there the spark can be quite weedy. The quality of a coil will affect the speed at which it can build it's field and the stronger the field the greater the power generated when it collapses. You have 3 times the problem on a V12 which is why <!--EZCODE LINK START--><a href="
http://www.vintageperformance.com/" target="top">pertronix</a><!--EZCODE LINK END--> (Aldon in the UK) rate their coils by cylinder.<br>
<br>
Needed for normal daily driving? Probably not but this is a fast road engine thread. Scott has the best possible proof of the benefit.<br>
<br>
Tin
<p>1978 <!--EZCODE LINK START--><a href="
http://www.triumphowners.com/704">Dolomite Sprint</a><!--EZCODE LINK END--> Blue, a bit tetley. - Current daily drive.<br>
1972 <!--EZCODE LINK START--><a href="
http://www.triumphowners.com/754">Spitfire IV</a><!--EZCODE LINK END--> No name, in bits.<br>
1968 <!--EZCODE LINK START--><a href="
http://www.triumphowners.com/705">GT6 II</a><!--EZCODE LINK END--> Little blue, nice!<br>
1973 <!--EZCODE LINK START--><a href="
http://www.triumphowners.com/755">Dolomite Sprint</a><!--EZCODE LINK END--> VA41, seriously tetley.<br>
1980 <!--EZCODE LINK START--><a href="
http://www.triumphowners.com/864">Dolomite 1500HL</a><!--EZCODE LINK END--> Orange, really quite tidy.</p><i></i>