Lights and Boxes

This edition I want to deal with a couple of tech subjects that I get a lot of questions about: auxiliary lights and gearboxes.

Lights

One of the first things I observed when I became a rally fan was that rallyists got to use waaaay cooler lights than the rest of us did. You may not believe this, but I wanted to get into rally in part because I wanted to get the cool lights.

My Mitsubishi Evo carries six auxiliary lights: two pencil spots and two driving lights on the hood pod, and two “cornering pods” on the bumper, each with one fog-type light. Pencils are designed to give maximum long-range light, drivings to light up the road for quite a long distance, and cornering lights actually shoot off the bumper at up to 30ْْ to the sides so that when you’re sliding sideways you have something shooting down the road.

I use twin-filiament PIAA 80 Racings for the spots and the cornering lights – these have the advantage of using H4 bulbs and so can be switched to low beams with a sharp cutoff in the event of dust or fog. For the driving lights I use Hella 4000 HIDs which give a very white light and complement the relatively yellow light of the PIAA 135/90w H4s – I don’t actually like having all HIDs as the white light doesn’t give as much texture as the normal halogens, although they are very bright.

Aside from what I personally use, I can give you some advice as to what to use on your own car, for the street or for motorsport. In the first place, round lights are always optically superior to rectangular or square ones. The fact that a bulb is in the centre means that maximum diffusion is achieved with a round pattern. Yellow bulbs and lenses are a thing of the past and should be avoided – there are now better ways to prevent glare in fog. As far a single filament halogen bulbs are concerned, H2s are superior to H3s and H1s as the filament is linear rather than lateral, so the reflector gets the filament in profile and has more source light area to disperse. H4s are bifilament and are very good if you can afford one of the few auxiliary lights that use them: the PIAA 80 Racing, one of the IPFs, and the Cibie BiOscar.

HIDs are powerful, take lots of current to fire but little current to burn, give a very white light, and are high beam only. Of course they’re expensive – a proper pair of auxiliary HIDs are at least $1000 a pair. I like them as a complement to other lights but I don’t think they’re strictly necessary – consider all other options before opting for these.

New technology uses the reflectors of the light rather than the lens to disperse the light – you’ve seen this on the headlights of recent road cars that have clear lenses and computer-designed reflectors instead of complex lenses. There is no doubt that this is a better way to get the maximum amount of light the maximum distance down the road. But for wash lighting near the front of the car I still prefer dispersion by the lens, which is to say I still prefer traditional white “fog” lights as cornering lights. For driving or pencil beams you can consider clear lenses with computer-designed reflectors.

The key in having a group of auxiliary lights is in having a portfolio of beam patterns. If you can have only two lights I recommend one driving and one fog (I know that sounds weird, but that was the standard in the 1960s, for good reason). If four lights, then two driving and two fog. If six lights, then two pencil, two driving, and two fog. Always make sure they’re beamed properly, and are switched with the high beams so you can turn them off and not blind oncoming traffic. Keep in mind that there are maximum candlepower restrictions in the various provinces – don’t break the law with your aux lights.

Gearboxes:

A normal synchromesh gearbox works well enough for normal driving on normal roads. Gears are cut on a helical angle to give them more surface contact area and to allow them to take up with each other on an angle for quiet operation. Cone synchros allow the gearbox shafts to be rotating at different speeds and equalize on shifting so that shifts are smooth even without double-clutching and rev matching. And ratios are spread out enough so that top gear gives fuel-efficient cruising but the lower gears are sporting enough around town.

Everything that a street gearbox is, a proper racing gearbox is not. Instead of cone synchros, a racing gearbox has simple “dog” tabs that lock into the next gear like the treads on your boots lock into the mud. There is absolutely no resistance to shifting – not only can you click from gear to gear in no time at all, but you don’t even need to use the clutch. This is a great advantage when left-foot braking into difficult corners, as you can just run down through the gears while keeping your left foot on the brake and rev-matching with your right foot. But the downside is that you can’t be at all slow on the shift or the shafts will begin to idle and you’ll have to crash it into gear. Also, if you’re idling on the start line (or anywhere) with your foot off the clutch and you happen to bump the gear lever, there’s nothing stopping the gearbox from engaging and you’ll soon have a stalled engine and perhaps a broken gearbox.

Dog rings, by their nature, engage by wearing, and so every couple of events you’ll have to rebuild the box. Budget maybe $500 in parts per rebuild, not counting the hours to remove/replace and open/close the box. Of course, against a $15,000 purchase price, that doesn’t seem so bad….

Our ‘boxes also use straight-cut gears which are noisier but stronger, and more closely-spaced ratios with a lower top speed than a standard street ‘box. We need more gears to keep the engine in its most powerful range on all the twisty roads, and on only a few occasions do we get to keep our foot in the throttle until we hit absolute top speed.