HERE<\/a>), it was running a generic engine map, which, because I did not know any better, I figured was fine.
\nBut it was not fine.<\/p>\nI learned this after running it on APL Performance\u2019s high-end dyno.<\/p>\n
Not all dynotuners or dynos are the same. This was something else I didn\u2019t know.<\/p>\n
Most dynos are economy-based units. Cheap and cheerful 500kg concrete drums which the back wheel turns while a computer makes calculations, and a tuner presses its keys searching for the right air-fuel mixture for the engine map. Most of them shove a single sensor into the exhaust pipe and take their readings from there. Of course, those readings are a combination of what all of the cylinders are emitting.<\/p>\n
Proper dynotuning means taking readings from each individual cylinder and adjusting stuff from there.<\/p>\n
APL does proper dynotuning. Its dyno is a high-end custom-built scientific extravaganza full of magnets, fans, and climate control which takes measurements every 1000th of a second. Adam also told me lots of other technical stuff, which is what happens when engineers talk about the stuff only they understand, but I understood very little of it.<\/p>\n
He also told me that: \u201cWe do a a dynotune, not a dyno show.\u201d<\/p>\n
That kinda stuck in my head.<\/p>\n
The first run, to see what was what, revealed the donk was running rich in places and lean in other places. It went up and down like a junkie\u2019s heartbeat.<\/p>\n
What the graph needed to show was a consistent and even path through the rev-range. What it was showing was peaks and troughs.<\/p>\n
\u201cThis is bad?\u201d I asked.
\n\u201cIt\u2019s great if you only ride at 3622rpm all the time,\u201d Adam replied.<\/p>\n
\u201cWhat would have happened if I took it to the drags?\u201d
\n\u201cYou would have got a few runs, then it could well have shit itself because it\u2019s not being fuelled properly.\u201d<\/p>\n
\u201cYou can fix this?\u201d
\n\u201cI can fix this.\u201d
\nAnd so he did. Here’s the video<\/p>\n