0.659 5th Gear Upgrade Report
Firsty, my thanks to Mike for doing such a professional job and for his hospitality and patience answering my basic (not to me) questions about the A2.
With a mapped 75 my expectations were that I would end up with a 4 gear box with overdrive that would suit the high amount of motorway driving I usually do. What I found was that I still had a 5 speed box - i.e the step between 4th & 5th is not too big. Sure you need to change up at higher revs, so will have to adapt the way I drive the car, but the gains of driving at higher speed with lower revs make it a much better car to drive, it feels a more powerful car on the motorway. The only problem is that you are tempted to drive faster because the car is smoothly driving along at 70mph approx 2,200 rpm which is right in the power sweet spot so the meerest touches on the accelerator and you are up to 85mph and beyond.
Is the car quieter - YES, but not a major reason to have this done.
What about MPG? Well at the moment the jury is out. Let me explain
I had planned to compare the mpg on the way up to Mike with the return journey over the same route, but the traffic gods were against me as the TMC directed me A21/M25 West/M40/M6 etc and on the way back across the peaks/M1/M25 East/A21. So the only comparable part of the route was A21 but again the conditions were different (time of day, traffic etc) so it was not an exact comparison.
On the way up the A21 is a mix of A roads and dual carriageway and I averaged 58mph (roads were clear at 3am) and achieved vis DIS 59mpg. When I hit the motorway I set the cruise to 70mph and before hitting traffic south of Manchester achieved 57mpg.
On the way back I tried to start measuring from the M1 but could not use cruise due to traffic and there are big sections of 50mph avg speed checks, so I resorted to measuring over short distances. At 70mph, I was getting around 59/60mpg which was disapointing as i was not using cruise (that tends to return poorer mpg figs). In the 50mph sections I was getting about 66mpg, which was lower than expected. I then hit the M25 carpark, so stopped all measuring until the return stretch of the A21 where I achieved 70mpg (compared to 58mpg on the way up). This figure was of course much better. So from these figures you could say that at the start there was marginal improvement, then the figs got worse, then they got better. The bottom line is that this was not an accurate enough test and also I think there will be an element of the gearbox settling down.
In summary, not sure if the mpg saving will be that significant and if you rarely use a motorway I would say this upgrade is not for you but if you do regularly travel at 60mph and over then this is a dynamic upgrade that will enhance your A2 experience.
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