Giving it some thought, I think a turbo is a great idea and probably the way of getting the inlet manifold to work really well. The speed of "stuff" increases with pressure, so any important tuned effects are lowered in frequency, or required lengths become shorter.
I was yapping to a guy who used to race an 850 short stroke (50mm crank) and it used to rev to something like 14000. The problem was that it did about 6mpg. He had a pretty highly developed head on it, it was some kind of 8 port as well....may have been a howley SOHC....I forget.
That kind of shaped my approach to the A series. Big engines were always expensive and ultimately limited....it was better to make the most out of shorter stroke things. I started on Morris Minors with a David Vizard book I got at a bootsale. I never had an engine come to bits on me, it was always a case of putting in a longer cam, bigger carbs and lowering the final drive. I was about 19 and picked up a 1275 engine out of a racing midget. I put the backplate and flywheel of the 803 Morris Minor on it (what a fool) and used the standard magic wand box (Morris Minor S2). That had twin 1/3/4 carbs, needles off something at the scrapyard which I tuned with a file. If I was doing anything but going dead ahead, it would break traction in 3rd gear (standard road wheels -sleeper!) After I crashed it, the engine went into an Austin A35. That had midget brakes and a 4.7 back axle (I think). It was bloody mad. It was in fact stupidly dangerous. It accellerated like a superbike and handled like a fairground ride. I didn't get into tuning suspension until minis, a while after.
Anyway, the minis went along a similar route....get a big bore engine and make it swallow as much air and fuel as I could. The 1430 I have wears a full on race cam and it's purpose is to make the mini go as fast as it will. It's a road going racing car.
I suppose the 970 engine is something that if built properly has the potential to really make the most out of it's capacity. I think it can be tuned to be the most credible of all the A Series Engines. If I had one, I would look at bi-charging it. Supercharging is great, but you are losing about 25hp at full whack, if you were to blow through a supercharger with a turbo, you'd make the dP a positive figure, which would mean that it took a negligible amount of power to spin it. When the supercharger is sucking, you can have a flap open so the intake turbine isn't a resistance.
There seem to be a few schools of remaining mini-ers
1. The restorers. Put it back as it left the factory....put on a normal carb, remove the weber box and bucket seats.
2. The wallet-racers. Pay £3k for a swiftune gearbox and KAD another £20k for something which could be beaten by a Focus ST.
3. The classic mini tinkerers and shed developers. The people who are bodging various cylinder heads onto various blocks and achieving outcomes in excess of some of 2.
I have a good mate who was in mini racing in the beginning. He said they had a 59 mini with 2 engines, the road engine for driving to work and the race engine which was so mad, it needed to be tow started. Another one of his chums had the radiator in the passenger door with a kenlowe fan blowing it....I think their weber was in the cabin and another (who worked at ST) had a cabin blower (marshall rootes) in the footwell. The engine oil used to periodically be diluted with petrol!!! Mike stopped mini racing as Vita pretty much had "£10k to spend on an engine, whereas we got ours at the scrapyard and built it on mums coffee table"
It's saddening that this insane spike in mini prices have pretty much killed off the 3rd type of mini racer. I barely see minis anymore, it used to be awesome, parking up and having to explain the ins and outs of my car to enthusiasts.
You owe it to the remaining "type 3 enthusiasts" to make it rev to 11,000 and make people say "what the hell has that got in it? a bike engine!" and then you can explain how it has 130hp per litre and how this is derived.
