Dan Rogers 750 Roadsports MX5 Snetterton

750MC – Snetterton

Qualifying 5th (18th Overall) | Race 6th (18th Overall)

Since last round at Donington Park, I’ve improved on the aerodynamics as planned. This is just as well as Snetterton is a fast track which favours cars with higher top speeds. So there’s new slim wing mirrors, and the old quarter glass windows have been ditched in favour of some custom made Lexan polycarbonate items that hopefully will reduce wind turbulence. The rear deck section has also been filled with vinyl to try to reduce the parachute affect I believed it was having.

Did it all work?

Hard to say for definite but comparing back to last year, we are +5mph quicker at the end of the straight, and that’s probably a combination of other recent changes too. There was dramatically less wind buffeting from where I was sat, and I think the camera is picking up less wind noise and has more exhaust note instead. That’s not a definitive result of progress, but it’s an indication that things have improved!

Qualifying was close

Positions changed on the last lap of qualifying, with 3rd & 4th places both improving so when I thought I’d improved enough on my final lap – I hadn’t quite done enough. Still, we were 0.9 seconds off pole with a 2:16.6, and I was happy with that as it was the fastest lap of Snetterton I’d ever logged. More impressively, it was 7 seconds  than the cars running in the MX-5 Championship on the day (which was the spec of my car before we started the engine upgrades a few years ago). Full results here

Opening lap was hectic

As ever, best to let the video do the talking here. I got a bit boxed in on the start but managed to pull off a couple of moves around the outside to gain places back. Ultimately straight line pace hindered my ability to maintain those positions which is a bit frustrating but there you go – every car has different strengths and weaknesses depending on the track.

After the race

In a way, this is where things got interesting. We were weighed and then asked to go to the dyno. 750 Motor Club try to dyno all the cars in the Roadsports at least once a season to ensure that everyone is within the power to weight ratio for their class. Our class (C) is 200hp at the flywheel per tonne, measured without the driver in the car. The Mazda weighed in at 860kg which means we had a maximum power figure of 172hp if we were to remain ‘legal’.

On the day the car produced 158.5hp which was quite a lot lower than we thought based on it producing 167.5hp on our usual dyno. But I see this as good news, because providing we can unlock that power from the engine without spending a fortune, there’s another 13hp which we’re losing out on compared to the others.

Time to read up on ways to get more power, and also think about some further aero changes including a front splitter / undertray in the 2 month gap we now have in the calendar until Brands Hatch.

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