BMW 330e BTCC : Inside WSR's Touring Car challenger
Welcome to The Race Bay and indeed welcome to some race bays! Now, here on this channel we love talking about motorsport engineering And where better to do some filming than here at West Surrey Racing Sixteen-times British Touring Car Champions And we're here to talk about the BMW 330e This is BMW's famous 3-Series as most of us know it It's a nice, practical car for the executive on the move Fitted out with fine leather upholstery and all electronic gadgets Which makes for some fantastic road cars, but these aren't road cars, these are race cars These are cars built up specially for the British Touring Car Championship And we're going to have a deep dive to look under the skin of these race cars. So now, we're down in the race bays, and joined by Dick Bennetts Dick, thank you for inviting us to the factory today Fascinating setup here. Huge wealth of history in Touring Cars. Yes, we've been doing it for a few years, we moved from British Formula 3 to British Touring Cars in 1996. We initially started with the Works Ford Supertourer and then we switched to the Hondas then we switched to MG Rover when the regulations changed and then when the rules changed again we switched to BMW's Super 2000 E90 and we won our first championship in 2009 with Colin Turkington.
We've been with BMWs ever since, from 2017 on we've been assisted with BMW by BMW UK. Here we have one that you've made earlier, as they say. Take us through the process of building a Touring Car from scratch What is the initial building block, what in terms of the chassis do you get from BMW? The regulations, the BTCC regulations you must run a production shell, you must run production doors, you must run production bonnet and boot then every car on the grid has a similar sub-frame front and rear. The shells we get from Munich, we have one here, then there's a lot of work prepping them.
They have to have an FIA safety cage, that is designed by WSR (West Surrey Racing) to FIA regulations We used to build all our own shells here, but it is more cost-efficient now... we have a company WPMS (Willie Poole MotorSport) He builds our shells to our drawings, so that's his professional business. We used to have fabricators full time, but with so many control parts now it's hard to justify having those fabricators employed all year Ok, so that will then get you effectively a body in white with the rollcage now we're talking rollcage in touring cars, it's not just there for protection it actually forms the chassis, the strength of the car itself Yes it's quite crucial we make it as light as we can, obviously, within the regulations These aren't crash-tested with the rollcage, but that's all done with computer simulation by the FIA, isn't it? Yes, the FIA and Motorsport UK, we have to submit our drawings to them they run it through a simulation program, computerised, and "yes or no". Also, this current 3-series BMW is a very strong chassis itself, we're quite impressed how good it is.
And then you start the fit-out, and, well, we'll talk about the sub-frames in the engine separately but in terms of the driver's "office", the driver has got a really unusual seating position they are really far back, I don't even think my seat goes that far back on my saloon car. What was the thinking in terms of the driving position? It's all to do with weight distribution and C of G (centre of gravity) We try to get the drivers as low as we can, but also we get them back as far as we can There's a regulation; furthest-most point of the front seat, it is not allowed to go beyond the rear squab - we have it right within a millimetre of that. The regulations also with the rollcage, the B-pillar cage here, We have that back 2 degrees to allow us to get the seat back further That's the FIA regulation, so everything is taken to the limit of the regs. Because the BMW road car is actually 50/50, we try and achieve that with the race car Up till we went to hybrid we were achieving 50/50. Now we're 1-1.5% over.
Another job this winter is to try and get it back to 50/50 the regulations change quite often to not help us! Moving onto the driver controls, obviously the steering wheel gets brought right back and the dashboard almost disappears now in terms of what you would have brought across you in front of your executive BMW now you just have a small dash display Yes, the steering column is all bespoke made for us, but designed by us It also has a collapsible column in case you have a big front-on accident The steering wheel is nothing as complicated as Formula 1, but it is much more complicated than what it was 2 years ago because now the BTCC regulations, we have to run hybrid, so there's several buttons on there, all to do with the Cosworth Hybrid System. They have a display here which is for the gear lights, for gear shift we have another Cosworth panel... It's all Cosworth equipment, all the cars have to run the same system. Driver safety-wise, we have the nets, we've always had the net here, but now in the last 2 years we've had to put a net in the middle as well You'll be able to see later there's the hybrid battery in there, which alone is 27 kilos. The whole hybrid kit alone is about 60 kilos in weight, so most of that lives where the passenger normally sits. And that's your job for the winter. Going back to the summer, driver comfort, obviously they've got a lovely comfy seat there
I see a big hole in the back of the seat, is that ventilation? Yes, that's for driver cooling, some drivers like the cooling into their helmet, some have them into their lower seat Some have a fan blowing on their face, so it depends on each driver what they prefer And the British Summer of course (laughs) Yeah, occasionally, but we did have a couple of hot races, but generally… we’ll probably need heaters at Brands Hatch So that's the shell and everything inside with the driver, lets go now and have a look at the front of the car with the sub-frames and the suspension So, Dick, we've now got the complete front of the car sat on a trolley in front of us Obviously now the standard BMW wouldn't be like this, and in fact going back in history, touring cars wouldn't have been like this either. So why have we switched to a sub-frame now? In the early days when we ran the E90, that was very much a production BMW, BMW engine. Now since the rules changed in 2012 to NGTC we called it (New Generation Touring Car), the agreement was then to equalise cars Some road cars are easier to be made into a race car than others. So every car on the grid now, no matter whether it's front wheel drive or rear wheel drive has to run the same front and rear sub-frame. RML are the people who produce them for TOCA, and they do the wishbones, uprights, sub-frames, steering rack Brakes are all AP as well, so the sub-frames are a crucial part. You're not allowed to change anything here But it's how you design your shell to hold the sub-frame is an important part as well.
Okay, so we've obviously got a whole range of production cars racing now, in the British Touring Car Championship, all very different structurally inside but it's not that the sub-frame actually attaches to the front of the body shell that's had maybe bits cut off it, it's actually connecting to an extension of the rollcage Rollcage, yes and that's one of the crucial design parts we do, is the stiffness of it all when it's installed to make sure it's doing what we want it to do, and what proves it to me or to us is that when you make a small adjustment, some people think a touring car's not like a single seater, but trust me, we can change the ride height 2 millimetres, 1 degree of wing, 0.2 degrees of camber and the car is better or worse Wow and that's due to the stiffness package of the whole installation. And that's also due to the fact that although this is a standard sub-frame, there's a lot of adjustability for the suspension geometry. Obviously you're running Rear Wheel Drive, slightly different weight distribution to the Front Wheel Drive cars but it's all quite different, it's all super secret stuff as well? There are a lot of permutations within the geometries, from roll centres to dives and squats and camber change so yeah, that's quite a crucial part on how good a touring car works.
and it's fascinating that touring cars now, as effectively given, the front and rear sub-frames are identical it's obviously modified slightly so that you can get your different orientation of engine and we'll go and have a look at one of the rear sub-frames in a moment as well Yes, we're north-south being a BMW - the production road car - is north-south the packaging from the front of the sub-frame forward is all down to us; the radiator positioning, although it's tied to regulation as well, the intercooler positioning and all the ducting at the front is all WSR-designed. Okay, and we were speaking earlier about the intercooler which you can see stacked above here, now that is a spec part to a degree, isn't it? Yes, the actual core of the intercooler is a control part, so every car on the grid again has the same core, but then it's down to each team to how they install it, so the end tanks are designed by us. Again just showing how the standardisation just makes this sport so competitive and affordable at the same time Yes, it's... here, for example, is a separate water system for the LTR with a pump each side, We have three separate water systems on the car, now we have one for the engine, then we have a completely separate system here for cooling the EV motor which is in the bellhousing in our car, and then this one is a separate system to cool the hybrid battery, so it's quite complicated now, getting everything packaged and working. So you have little tiny radiators fed off the ducting at the front Yes, we call them an LTR (Low Temperature Radiator) Ah, I see and that's again a mandatory TOCA part and every car has to carry two of them.
Ok, so this is the front, let's just go and have a wander over and have a look at one of the rear sub-frames as well Yes So we're now at the other end of the car, this is the rear sub-frame, and again, this would be exactly the same if it were a front-wheel drive, obviously, except for the differential Yes, again every car has to run the same sub-frame but being rear wheel drive, BMW tradition, we carry the diff here again, it's like front-wheel drive, it's an X-trac part, very good gearbox I must say, very good. in the old days when we ran touring cars, you used to have to take the diff apart to do preload, now you can do it with a little spanner and you can adjust the preload Is that the little spring… Yeah there we go, down there So that's it! And that makes life a lot easier It does make it a lot easier! So, looking at some of the architecture, you've got double wishbone suspension, with the pushrods set up, these are spec dampers? Yeah, every car again, they're Penske dampers, but each team is allowed to develop them, but only with homologated parts so you have, I think, a selection of about four different pistons, and the shims varying from next-to-nothing through to whatever-you-want And with so many spec parts, this and the suspension geometry is where you start to find the magic in setting the car up, isn't it? It's how you set your dampers, how you get your suspension geometry working Correct, dampers are quite crucial, and Steve, our Chief Technician, he's been developing dampers. We are running one of the four cars with a slightly different spec, we are testing The other three are running, which is again new for 2023, a different spec to what we ran in 2022. As the tyre from Goodyear changed their spec, that affects how the dampers work, so we are tuning the dampers to suit a tyre, and also the different track surfaces Something else on there, which I hope you can just see at the very back here - nothing to do with suspension - At the back you have the air jack, and you have those on the rollcage inside the cockpit at the front? Yeah, two at the front, one at the back, so when you do a pit stop... ... nothing like the speed of F1, but if we change wheels in a race - because also we're restricted on the amount of people who're allowed to do pit stops - we do a hot pit stop in about... full wheel change... in practicing we do it in about 17 seconds but in reality it's about 22-23 seconds. Which is still massively impressive with such a big vehicle and with a limited number of people.
Okay, so now we're going to want to go away and talk about the next thing which attaches to the front here, which is the engine and the gearbox. Now we're at the sharp end of the car again, the sub-frame is in, the engine is in, and Dick, we've got a bare engine here to have a look at. Now, British Touring Car Championship has always been about production engines, what can do you to run an engine in the championship at the moment? You're correct, the rules are that it has to be a 2-litre production engine, which this is. We use the BMW B48 model engine, which is a fantastic road car engine, but also it's made a fantastic race engine. The regulations are 2-litre, but you could use an engine from 1.6, I think, up to 2.4, within the family, but this actual engine we use is a 2 litre production turbo engine So it makes a very good basis, it uses production BMW valves, cylinder head, production crankshaft.
NBE (Neil Brown Engineering) developed the engine so they've got racing rods in it, racing pistons, and valve springs. We actually use the road car fly-by-wire throttle body as well The oil system is all BMW, it has an electric water pump which is BMW, so the majority of it is a BMW road engine. And those are regulations that limit what you can do. Now, I can remember Touring Car engines used to be absolutely down on the floor of the car, this is raised up, and it still has a wet sump, why would the engine be so high up in a race car? It's actually the current regulations, the engine has to be as per your road car, and I've actually been campaigning for dry sump.
I used to build race engines, but the regulations are that it has to be a wet sump, so that's quite a lot of work for the engine builder because of oil surge problems; they're going so fast through corners. Yes, it is sitting in the chassis, but what you're talking about is a Super Touring which was a fantastic engineering exercise for designers. I used to love it, but the budgets just got out of control, whereas now the budgets are controlled to a level where it makes the racing better. Another thing that's fixed is the cam lift, and you're running your dedicated Neil Brown Cams? Yes, there is a maximum regulation of 11mm valve lift, and NBE designed the cam shift to be 11mm valve lift, so everything is done to the limit of the regulations. Compression ratio is fixed at 11 to 1. In the Super Touring days, I believe one of our engines was up at around 14 to 1.
it's done now, we can get through a whole season on one engine, so we do about 5,000 to 5,500 kilometres per season. And again, as we've spoken so much about specification parts, such as the turbocharger, and also you have a limit on how different all these engines are apart, because, again, you can have your road car engine, you can have a specific- TOCA, yes -touring car engine as well, and they're all within a few horsepower of each other Yes, TOCA - the organisers - they flow test all the engines before you run them, on the inlet side, to check how much air gets in. They determine your boost level for your turbo, and it's pretty accurate, they get it pretty close. Sometimes different teams have a little bit of a gripe about it, but generally like last weekend at Silverstone, in qualifying, there were four cars within four hundredths of a second (0.040s)
and they were all different make chassis, so... …It's working! And they run on control tyres, so that helps as well. Some meetings we have a Soft tyre, generally the Medium compound, and then places like Thruxton we have to run the Hard compound tyre for safety. Yep, ok, so that's the power unit. What kind of headline performance figures are we talking about for this? I can't divulge that! [BOTH LAUGH] It's a very good engine, we believe all the engines are within 5 horsepower of each other, NBE don't give us dyno sheets. They build them, dyno them, but we think most engines are up around the 390 horsepower mark now. Wow!
Ok, so, we've actually got the engine backwards; you're looking at the back of the engine that would then go back along the car, so you can see the clutch there. Now, it's not just a combustion engine, is it? There's also the hybrid system which Cosworth has now introduced. On the clutch, that's another control part, it's a carbon clutch from AP, very good clutch As you say, behind that, for the last two years we've been running hybrid so for a rear wheel drive, the EV motor is actually in the bellhousing, on a front wheel drive it's separate to the gearbox and under the bonnet.
Ours is much harder to get in and out if we have any issues, we used to have some temperature problems with it. Now we've resolved them by using 3D printed little cooling ducts on that, so it's been great. We have a technical alliance with Midlands 3D, and they've been producing a lot of 3D printed parts for us, which has been fantastic with the speed you have to develop new parts. And then leading back on from that, within that bellhousing you were talking about, is the sequential gearbox, which oddly, is the same for the front wheel drive and the rear wheel drive, in essence, even though they're very different installations.
Yes, it's an Xtrac from Newbury, fantastic company producing it the gear ratios are virtually identical whether front wheel drive or rear wheel drive. TOCA can then monitor to keep accurate - they can log in and see what speeds, what gears you've got in, because we have to homologate what ratios we're running. We have to hand a form in on Saturday, if we change the ratios on Saturday night, we have to inform TOCA.
We use the longitudinal 6-speed Xtrac, everyone is 6-speed sequential, with a gear lever still There have been discussions on paddle shift, but the regulations are that we still have a gear lever. Excellent, and that then drives through to the drive shaft to the rear sub-frame that we were speaking about earlier Yes, the propshaft, I know that some sports cars run a carbon propshaft, but we're not allowed to, it has to be a steel propshaft, again we have an outside company make it to our specification. In the early days of running turbo we had a few propshaft failures because of the extra torque and power, so we've had to up the diameter and the gauge of the propshaft to cope with the power And development is continuing, fantastic Yes So that's what goes into making a championship leading British Touring Car! Many thanks to Dick Bennetts and the team, and some of the ex-drivers here at West Surrey Racing. Hope you've enjoyed this video here on the The Race Bay, and come back for many more!
2023-11-22 10:58
