Diesels in the BTCC

[sosidge]

Could someone tell me the differences in the regulations that have allowed the diesel cars to outperform the petrol cars in the BTCC?

As far as I know engine capacity is the same, obviously the diesels have turbos, but what about air restrictors, fuel ratings, weight etc.?

 

[markoos]

Heres a brief outline of the regs-
http://www.btcc.net/html/regulations.php
click top right regulations pdf gives a more thorough outline.

 

[ZBOYD]

They haven't outperformed the petrol's though, in fact they have been on the back foot at most of the rounds so far this year.

Snetterton went in their favour last weekend mainly because of the long straights and lack of slow bends where the extra power and torque gives them them a slight advantage at pulling away.

I think at Oulton Park you'll find them struggling more with the extra weight they carry over their front wheels compared to the petrol cars.

The diesels are built and race to the FIA Super 2000 diesel regulations, these are the rules and regulations that TOCA (ie the people who run the BTCC) say the Diesel Super 2000 class cars must adhere too.

If you want some light reading material the full regs can be found here - FIA S2000D tech regs - CLICKY

The Leon's run as follows:

Maximum power: approx 270 PS.
Maximum torque: 440 nm.

Base weight: 1150kgs (including driver) as far as I am aware in accordance with the regulation. Upto 45Kgs of success ballast can be added to this over the course of a weekend.

The fuel is monitored and supplied as TOCA controlled fuel.

BTCC Sporting Regulations Basic -CLICKY

BTCC Sporting Regulations - More in-depth - CLICKY

 

[nickleon44]

You might like to take a look at this article in Touring CarTimes (a great site for touring car racing news, BTW) -
http://www.touringcartimes.com/columns.php?id=5

 

[sosidge]

Well, the masochist in me actually quite likes reading all those technical docs on the FIA website (I understand your vices so much better now Max!).

Obviously SEAT have gone diesel for a reason, partly PR, but surely they know there is an advantage in the cars, WTCC performances show that, maybe the UK tracks/drivers aren't able to exploit it. I don't know.

The most interesting thing to me was that the original FIA regs included a 1.5 times multiplier for turbodiesel equivalency - ie just under 1.4 litre engines would have been required. I assume a little pressure from the diesel lobby let them run 2 litres instead. The multiplier for petrol with forced induction is 1.7 - a short stroke VW 1.4 TFSI could be amusing!

As far as I can tell, the diesels run approximately 30kg heavier, have a 35mm restrictor on the turbo intake, and have much looser restrictions on internal engine modifications.

I wish SEAT still ran petrol though - racing is about performance, Diesel doesn't perform unless the rules are skewed in its favour.

 

[m0rk]

actually SEAT had to drop the flat floor & aero package to make the diesel less competitive

they've not really been skewed, unless you consider the same has been done for petrol engines

 

[MarkE]

As far as I can tell, the diesels run approximately 30kg heavier, have a 35mm restrictor on the turbo intake, and have much looser restrictions on internal engine modifications.

I wish SEAT still ran petrol though - racing is about performance, Diesel doesn't perform unless the rules are skewed in its favour.

Heavier base weight (with the same size brakes) and an inlet restrictor are skewing the rules in favour of the diesel?

 

[sosidge]

Heavier base weight (with the same size brakes) and an inlet restrictor are skewing the rules in favour of the diesel?

Yes, they have a turbo.

 

[ZBOYD]

The rules are skewed far more in the WTCC. As a result they piss about so much changing things, that they go from one round to the next not really knowing what to expect from Petrol or Diesel.

However in the BTCC, TOCA have stayed pretty much loyal to the first brief of the regulations. The performance of the SEAT in the BTCC has been pretty fair so far. It had a good advantage at Snetterton and will likely have that advantage at Silverstone too. But the slower circuits seem to favour the petrols much more.

The fact TOCA don't arse about so much with the rules and giving one car more power, or one car better aero or less weight means it all pans out as it should. The SEAT certainly don't dominate, if that were the case why is a Vauxhall leading the championship.

As for why they are dominant in the WTCC, ask the FIA. Don't confuse the two championships. TOCA may use the FIA's S2000D regs as a basis, but they don't subscribe to all this tinkering that takes place.

The diesels are very much a PR marketing exercise on SEAT's front. Motorsport has had to change, it's about selling cars for the Manufacturers' just as it always was. But the bottomless pits of money that so excited us in the 90s has dried up with the motor industry having to radically change to compete. Just like any other business they need to satisfy the penny pinchers it's worth while.

SEAT are not the all conquering company in comparison to Vauxhall/GM and the might of BMW in the WTCC. If they are to remain in top flight motorsport it needs to be affordable, successful and worthwhile for them.

Sadly diesel's may not be sexy like petrol engines but its all about market forces at the end of the day.

I would much rather SEAT be competing, than watching Vauxhall race itself.

 

[JasonP06]

They haven't outperformed the petrol's though, in fact they have been on the back foot at most of the rounds so far this year.

Obviously having wrote it on the 16th it was before Oulton but for the second consecutive time, and forgetting for a moment to bog ourselves down in the complexities of technical side, fact is for whatever reason, though in terms of pace the diesels are getting better and better, something is adversley affected the reliability particularly in both the second and final races of the day. I am wondering if it is something to do with the compatibility of the diesel engine with the reliability because I don't believe SEAT had this much problem with reliability last year - when they ran petrol.

As much as it is hard to swallow, in the cold light of day, perhaps 50% of the outright dominance of VXR and their ability to maintain of a large margin in points and performances over SEAT for most of the season is to do with the constant issues that are dogging SEAT. Not just the errors made by Jase and DT but of other drivers (i.e Jackson on DT at Croft and Chilton on DT at Oulton), but also the issues the Leons are blighted with.

Watching yesterday on TV and the results on tsl the only ray of sunshine for the manufacturer is seeing their Independent entry, Adam Jones in the TAC petrol Leon draw level on 201pts with 2nd placed Mat Jackson.

 

[Moley RUFC]

Could someone tell me the differences in the regulations that have allowed the diesel cars to outperform the petrol cars in the BTCC?

As far as I know engine capacity is the same, obviously the diesels have turbos, but what about air restrictors, fuel ratings, weight etc.?

They have to make the engines out of straw and blue tak

 

[UncleFester]

Sadly diesel's may not be sexy like petrol engines but its all about market forces at the end of the day.

I would much rather SEAT be competing, than watching Vauxhall race itself.

I agree with the above with the exception of diesels not being 'sexy' once a car is going you can't tell a well tuned derv from a well tuned petrol, well only that the diesel has a louder exhaust note and smokes a little more.

It shouldn't matter what engine is under the bonnet and whilst it still does there will always be that 'second class citizen' view about diesels. Not that it particularly bothers me on the grand scheme of things but it's hardly an objective view, especially given that a good portion of us are diesel drivers - i didn't realise this made us 'unsexy'.

Given that we'll all be running around in alternative fueled cars within 20 years ( according to Mr Brown) anything that makes a noise around a track will be 'sexy' whether it be petrol or diesel. I didn't realise that motorsport had to be petrol based before it was considered a proper sport.

This is of course why every new Cupra owner would cry into their petrol tanks should SEAT ever be stupid enough to make a proper Cupra Tdi. Funnily enough, that's the only Cupra some of us would be happy to own - if competing ( and hopefully winning) in the BTCC / WTCC is what it takes for that to happen then roll on that

 

[ZBOYD]

My point was squarely directed at the diesel in the racing world. Road cars and the diesel versus petrol debate is something entirely different altogether.

On a race track I'm afraid the diesel engine carries with it somewhat of a stigma, even the all conquering Audi R10 has it's detractors. In motorsport circles they are not seen as being 'sexy' and sadly however you sugar coat it they are unpopular in the arena of motorsport.

Not that I don't want SEAT to succeed with the diesel, I do very much. It's looking likely that it will dominate this years FIA WTCC. However the BTCC team have had more than their fair share of misfortune and unreliability.

Diesel's in the marketplace well that's a different arguement all together as I say. Diesel's are popular because they are affordable and cost efficient to a certain extent! Someone such as myself who covers no more than 5000-6000 miles per year would say a diesel isn't really a neccessity. No doubting that modern diesels have performance to match their frugal savings. But it's not performance that can be measured on the same scale as the petrol engine, though the petrol engine will suck your wallet dry.

If my circumstances changed and I was travelling much more then the Cupra would be something i'd have to sacrifice no doubt.

However totally different subject that, and that's not what the thread is about.

 

[UncleFester]

Fair point Z - I didn't realise diesel still had such a stigma within motorsport circles, the R10 is lovely, not that i'd turn down either the R8 or the R10.In which case all we can hope for is that they sort out the unreliability issues - it's not as if their petrol counterparts were perfect out of the box in every race.

 

[warren_cox]

Have the WTCC cars been suffering similar issues to the BTCC cars. They run 2 races a day and you would think in testing these issues would bare themselves out.

I was fascinated to see SEAT were going TDi when the announcments broke. I immediately had visions of understeer, strained braked and excessive tyre wear but never assumed for a minute reliability issues would dog the ever reliable diesel lumps.

The petrol / diesel comparison is running a bit thin these days. Both engine types are now highly capable, and both have their pro's and cons. To be honest its horses for courses but I still love the sound of a V shaped petrol lump over any diesel as it sets your soul stirring. The diesels are brilliant (when they work), but you get an in camera shot in a BTCC Leon and there no real tune to it.

I'm glad SEAT persist with their racing, as without them I'd have no-one to support in BTCC. Watching the BTCC has been agony in the last few races with all the opportunities that have just blown away into the weeds. What a shame.

 

[Leonidas]

Wasn't the old 2.0 FSi petrol uprated lately. Adam jones car seemed to be able to hold off everything. Could SEAT sport UK might go back to petrol next year

 

[m0rk]

There's a high output TFSi engine available, but with a weight penalty

 

[Leonidas]

Does any1 run it ???

 

[m0rk]

Tom Coronel did in WTCC, but I don't think Adam does

 

[ZBOYD]

The petrol hasn't really been a great qualifier either. Jonesy did well in race 3 but it was only race 3 after a grid reversal that he was in firm contention. Its not really worked out for him at other circuits like Snetterton where the petrol Leon was well beaten.

If it wasn't for the terrible luck and this unknown misfire problem the diesel not only qualified better, in race 1 Plato left the field for dust. His pace in race 2 before the misfire developed, proved that full ballast wasn't troubling it too much either. At least in the early part of the race.

If they could nail down this terrible bout of unreliability, I doubt VX would have an answer to the performance of the diesel really.