DAVE ON DYNOS, ELECTRIC PARKBRAKES, STRINGING YOU ON

Iwent to a dyno day last weekend. Run by a car club I’m kind of, sort of, loosely associated with (as in, I’m not a member, but I know a handful of blokes who are). It was staged at a big, flash, spotless, shiny-floor workshop of a major race-prep shop.

Now, I’ll be right up front here: I don’t really like dynos. I don’t like standing anywhere near them, especially when there’s six litres of angry, supercharged mayhem strapped to the rollers.

I’ve seen what happens when a clutch or flywheel explodes and, frankly, I don’t want to be anywhere near it. Fortunately, in this case, the day was run by a team of people who understood safety and while there was plenty of space to see what was going on, none of us civilians got to close to the action.

The other thing I’m not mad about when it comes to dynos is the savagery they dish out on a car. I’ve seen too many videos of cars coming off those stupid, single-roller dynos the Americans tend to favour. Likewise, I don’t enjoy the thought of my engine going from full load at redline to zero load when the operator steps off the gas at the end of the run. Ever heard of rod-stretch? It’s enough to give a tappet-head nightmares.

Again, though, the mob we were dealing with on the weekend had all those bases covered. For a start, the dyno is the much safer, double-roller variety which not only reduces massively the chance of the car stepping off, but also ensures the car is always centred on the rollers. And it seemed to me that once the run was done, the dyno decelerated the engine a bit more gradually than simply the equivalent of stomping on the clutch like it was doing a plug-chop.

It was also illustrated to me exactly why you would use a dyno. Okay, we were just there to see who had bragging rights at the next club meeting, and who was going to have to shout the bar for having the most feeble output. But one of my mates stuck his electronically-injected later-model engine (In an Anglia 105E, but you get the idea) on the rollers and cranked out a pretty good figure. Pretty good, but not stellar.

And that’s because the engine didn’t want to rev out to its full 7500rpm. Instead, it started to lean out at about 6500, leading the dyno operator to pull the pin at that point. This is what I’m talking about. Because the operator could see exactly what was going on with mixtures and what-not, he was able to cut the run short to avoid any damage.

So while I was once inclined to do things the old fashioned way using a deserted stretch of road (or, God’s dyno as I like to call it) I have to admit that in the same situation, I’d have revved the car hard in a lean-mixture situation. And maybe damaged something or even blown the thing to smithereens. Thing is, this car has been on the road for a few years now, and this was its first dyno run, so my buddy has been driving it around with it leaning out at the top end for thousands of kliks.

This revelation comes a few weeks after I strapped the RA40 to the dyno for a tune. I wasn’t real happy about it, but now I’m much more comfortable with the thought. And it’ll go back on the rollers when it goes back for the final fiddles on the twin Solex carbys.

For the moment, though, I’ve been having a tweak at home and the results are actually pretty promising. There’s still a small flat spot off idle, but now that I’ve fixed the monster vacuum leak, the thing is much happier. Most recently I’ve wound the mixtures in to roughly where they should be and managed to synchronise the two carbs pretty accurately. And the little orange nugget is fairly flying. Relatively speaking.

Actually, that’s another thing I’ve had to put into perspective. Once upon a time, the 18RG was the last word in Toyota performance; nothing could touch it, especially not in its class at Bathurst. Nowadays, of course, it wouldn’t see which way a hot-hatch went, but it’s still quick to the point of being entertaining. Which in my book, is just on fast enough.