25th July, 2002 - I'm currently using Bosch which seem to be fine. I have been disappointed with Halfords own brand in the past. The issue here is primarily the accurate positioning of the filament in the parabolic reflector. In fact only the dip filament is at the point of focus; the reflector then produces a beam of parallel light that is acted upon by the numerous prismatic elements built into the lens glass. Because obviously only one filament can be at the true point of focus. The main beam filament throws light out in a much less controlled way; this is obviously no great concern, for practical purposes, but it is very helpful if this axial filament is truly on the axis of the reflector. The main beam then goes in the right direction, when the dip is correctly aligned; the only adjustment you have. With this in mind, you can see that the physically larger filament of higher power bulbs must be further away from the point of focus; and therefore less controlled by the lens elements. Jon.

25th July, 2002 - The headlight wiring is protected by a 7.5 amp fuse. The wiring itself is 14/0.30mm; this rated at 8.75 amps max. A 90W filament draws 7.5 amps. It is clear Porsche allowed a reasonable amount of 'head room' so the wiring itself didn't cause a voltage drop to the filament. Going beyond this wattage (90W) will certainly cause the wiring to heat, negating the light gain and heating the wiring dangerously also. I would urge anyone to check their wiring very carefully with the standard bulbs in, before up rating the bulbs. As any problem here (that may be prompting the replacement) will only be exacerbated with bigger filaments. Secondly, if you must fit the larger bulbs, check that the wiring to them doesn't get warm after a few minuets use. If it does, you have gone too far! A decade ago, I lived in the middle of no-ware, and fitted 100/90W bulbs, along with a custom HD loom, relays and fuse box. I noticed people only flashed me when the headlight lenses got dirty. I concluded the layer of dried salt and road dirt diffused the well focussed light. This scattered light then caused oncoming traffic a problem. Having investigated the question of high wattage bulbs in some detail both theoretically and experimentally (see my previous posts), my recommendations are simple. 1, replace your headlamp units if they are at all 'iffy'. 2, make sure your cars system voltage is up to scratch. 3, minimise any voltage drop to the filaments. 4, fit standard wattage, high quality, NON blue xenon bulbs. This will give you good lights. It will also improve your cars charging and starting; and will work within the design parameters of your car. And not blind anyone. Or you can just slap in some cheap high wattage bulbs and pretend physics doesn’t apply to you. The choice is yours, Jon. 944 List

PIAA bulbs are DEFINITELY MUCH BRIGHTER although still standard (thus legal) 60/55W.
Phone Bob at A-PP 01706-347357. Part No EWC1.
Extract from my e-mail dated 16-10-00:- The correct ones for us are the 60/55W H4 EWC1 which gives an equivalent light of 110/100W bulbs but with identical current consumption. Price is :- EWC1 £40.96 pr (incl post) +vat.
Apparently he's never had a faulty one returned in over 12 months of supplying them! There are others (even brighter) he does but they're not legal!! - Dave B - 19th Nov, 2000

PIAA bulbs - I fitted a pair of these a while back, and was pleased with the results. However, did anyone read Autoexpress this week? They did a test of a gazillion bulbs and guess what - the PIAA Super Whites, as fitted by yours truly and no doubt many of you, came last of 43...... Andy B
One point to note - the bulbs under test were H7 ... I don't know about anyone else, but I certainly fitted the H4 bulbs and have not been disappointed with the improvement in light generated by the bulb over the standard fitment bulbs. Is there a difference between H4 and H7 ? Has anyone tried the Philips ? - David K - 2nd Feb, 2001

I fitted the H4s to our 4x4 as well as the porker they are the best I have used. Haven't tried the Phillips. Michael R - 6th Feb, 2001

I also fitted the 60/55W H4 EWC1 bulbs and am very impressed with them. So much so that I even changed my fogs for theirs as well (ECB1). H7 bulbs are a totally different fitting. Interested to hear if anyone has fitted the Philips ones? Knowing Autoexpress whom I am not very impressed with, they probably tested 24V bulbs from PIAA?? - Dave B - 7th Feb, 2001

PIAA EWC1 headlamp bulbs @ £54.52 pr.
ECB1 front fog bulbs @ £35.96 pr. A-PP (Bob on 01706-347357) sales@a-pp.com - Dave B