Nissan LMP1 Discussion

[Articus]

Originally Posted by miatanut

But in 8MJ class, most of the braking was coming from the energy recovery. In 2MJ, most of the braking comes from the brakes. On the 8MJ plan, the back brakes were hardly going to do anything, and the front weren't doing much. In 2MJ class, both brakes have a lot of work to do.

Well yes but comparatively speaking, the rear brakes cannot do as much as they would in say the Audi because the Nissan already has a larger forward weight bias. The load on the rear axle is already reduced because of layout, then when you add the load transfer to front under braking, you will reach lockup on rear axle at a lower brake pressure. And if the Nissan is low drag/low downforce, the problem is exacerbated.

[miatanut]

Originally Posted by Articus

Well yes but comparatively speaking, the rear brakes cannot do as much as they would in say the Audi because the Nissan already has a larger forward weight bias. The load on the rear axle is already reduced because of layout, then when you add the load transfer to front under braking, you will reach lockup on rear axle at a lower brake pressure. And if the Nissan is low drag/low downforce, the problem is exacerbated.

I agree, but the point I'm trying to make is with an 8MJ hybrid system, for this design on the rear, motorcycle brakes would probably have been enough friction brakes to make it through 24H, or maybe 24H with one pad change during the night. Go to 2MJ and they have to go to "real" brakes of some sort. On the front, before and after a change from 8MJ to 2MJ, there is an even bigger change in brake load.

I'm afraid we are looking at a classic Chaparral. If it works, it will completely dominate. But, due to so many new ideas and a lack of development time to refine them, the thing as likely as not will break and finish last or darn near last.

[YorkshireLad]

Originally Posted by Articus

Well yes but comparatively speaking, the rear brakes cannot do as much as they would in say the Audi because the Nissan already has a larger forward weight bias. The load on the rear axle is already reduced because of layout, then when you add the load transfer to front under braking, you will reach lockup on rear axle at a lower brake pressure. And if the Nissan is low drag/low downforce, the problem is exacerbated.

Surely if it's going to be that biased, this thing will be a nightmare in the braking zones.

It will squirrel worse than the GTE cars, with the back end unpredictably moving from side to side. Or is that big wing put things in order but as the car reduced speed that wing will have less affect on helping to keep that car in line.

Reading the above comments, IF true this car has just been a nightmare, with bens head on the chopping board and nissan ready to become a laughing stock.

[Mike E]

Nissan driver line ups confirmed:

Gene, Chilton, Mardenborough
Pla, Krumm, Tincknell

http://sportscar365.com/lemans/wec/n...river-lineups/

[rdjones]

We now know who will drive which car:-

Max Chilton and Marc Gené will share the wheel of the #23 NISMO with Jann Mardenborough.

The second car will be driven by Michael Krumm, Harry Tincknell and Olivier Pla.

[miatanut]

Originally Posted by YorkshireLad

Surely if it's going to be that biased, this thing will be a nightmare in the braking zones.

It will squirrel worse than the GTE cars, with the back end unpredictably moving from side to side. Or is that big wing put things in order but as the car reduced speed that wing will have less affect on helping to keep that car in line.

Reading the above comments, IF true this car has just been a nightmare, with bens head on the chopping board and nissan ready to become a laughing stock.

They presumably went into this knowing the performance under braking would be a lot like a FWD touring car.

A bit exciting at times!

[CyberMotor]

How much can those long through body channels be tuned to provide different loads of DF? Or, possibly, the back brakes can be used in the first part of a braking cycle when at speed while they do have some downforce? Then when the forward bias dip begins, the braking is fully transferred to the front as the bias changes? Theoretically thinking here and not any of this can be done.

[MyNameIsNigel]

Originally Posted by MulsanneMike

Yes, the LAUNCH car certainly had 16s. But the images from testing show vastly different front wheel diameters being tested. Most certainly still 16s on the rear but probably 18s on the front. And I hinted at this back in January that there were concerns the KERS didn't provide enough braking potential.

French AutoHebdo magazine are reporting that Nissan were indeed running with 18'' rims at the front and 16'' rims at the rear. AutoHebdo further speculate that the larger rims and brake discs at the front may suggest that Nissan might be contemplating to ultimately run in one of the two lowest ERS classes.

AutoHebdo also claim that the technical issue that put an end to the Sebring tests related to weaknesses in the attachment between the front of the tub and the engine.

[TF110]

Yes it was said to be an engine mount issue.

[MyNameIsNigel]

Originally Posted by TF110

Yes it was said to be an engine mount issue.

That's very unfortunate as this may require some redesign of the front-end part of the tub, probably one of the items with the longest lead time. I hope they can modify or strengthen the tub as AutoHebdo report that the tubs for the two other cars were already in the process of being manufactured...

[ger80]

Maybe they can integrate an aluminium front bulkhead like Marrussia has in the F1 cars? Much easier to modify ...

[wdave0]

Originally Posted by miatanut

LOOK! Off in the distance! Is that a couple flywheels I see, to go along with the flywheel drivetrain?

You would think that when somebody came up with that, they would decide to not even show it to their client because it is an obviously absurd solution, and the real answer was to go back to the drawing board.

Actually, that's the time warp mechanism that makes any possibility of success.

[Maelochs]

Have to admit i am a little disappointed in Ben Bowlby--or Nissan, not sure if the design was off or a good design was constructed badly, but I didn't expect fundamental problems ... like the engine falling out.

[wdave0]

Originally Posted by Maelochs

Have to admit i am a little disappointed in Ben Bowlby--or Nissan, not sure if the design was off or a good design was constructed badly, but I didn't expect fundamental problems ... like the engine falling out.

Actually seems to be an exercise in poor judgment - to expect to create such a radical device in less than normal time with less than magnificent budget and then expect to be successful with it asks for problems.

[TF110]

Lets just wait until the season starts. Maybe theyll pull it off and contest for the podium at certain rounds. I think Spa should be good for their concept. But a place like cota probably wont let their car shine.

[Articus]

If one things is certain, building a sportscar is very difficult. Something we take for granted because of how easy Audi, Porsche, Toyota make it look.

The HPD coupe and the Strakka-Dome are examples of things unraveling at manufacturers who you just didn't expect to have these problems. It would not surprise if Nissan doesn't become strong until next year.

[Trebor123]

Originally Posted by MyNameIsNigel

French AutoHebdo magazine are reporting that Nissan were indeed running with 18'' rims at the front and 16'' rims at the rear. AutoHebdo further speculate that the larger rims and brake discs at the front may suggest that Nissan might be contemplating to ultimately run in one of the two lowest ERS classes.

But didn't last year's Toyota, in the 6 MJ category, also run on 18" rims? Once the rim can accommodate the required size of brake disc (maximum 15") and caliper, then there are other design factors involved in the rim diameter/sidewall height decision. The rear wheels and tyres on the Nissan are unique in size but 18" front wheel diameter is common in LMP1.

[philipp]

Originally Posted by TF110

Lets just wait until the season starts. Maybe theyll pull it off and contest for the podium at certain rounds. I think Spa should be good for their concept. But a place like cota probably wont let their car shine.

I don't think the Nissan will shine this year. They just don't have enough time.

Maybe they will show their straightline potencial in Le Mans, but I think that's gona be all for 2015.

hope I'm wrong.....

[TF110]

Originally Posted by philipp

I don't think the Nissan will shine this year. They just don't have enough time.

Maybe they will show their straightline potencial in Le Mans, but I think that's gona be all for 2015.

hope I'm wrong.....

In terms of top speed, thats how I mean for it to "shine". Spa, Fuji, China, Le Mans are tracks where the concept of their's should show its potential (if it works).

[YorkshireLad]

Haven't they changed brands of callipers...

Originaly they were running an alu coloured calliper and in recent photos I've seen AP racing.

[hcl123]

Originally Posted by TF110

In terms of top speed, thats how I mean for it to "shine". Spa, Fuji, China, Le Mans are tracks where the concept of their's should show its potential (if it works).

Well i don't thing they will shine in top speed either.

Sure the car does seems to have the 'aeros' of a greater speeder, but:

If they opt as rumored for 2MJ, due to technical difficulties, it will be very weak on launching power for a petrol engine, simply not enough 'torque' for a petrol engine most specially at lower revs ( electric motors are unbeatable at torque... instantaneous torque... and all other contenders are 4Mj or higher)

Then there is the brakes... or their system is as good or better than Toyota's, in virtue of having smaller and less potent 'disc brakes', counting on the 'regenerative braking power' as an extraordinary auxiliary... or they will be faced with the need to start braking earlier after a long straight (exactly where top speeds are achieved), adding the fact of the front config, the balance must be very good and cornering speed also very high ( at the best) for this 'earlier braking need' not being exacerbated...

If they solve the technical difficulties of the hybrid system, and if they solve the *balance* issues of all the systems... they can be a contender... but i can't see that in 2015...

[Articus]

If Nissan is planning on running 2MJ, I wouldn't think the car would be hot in a straightline either.

Once I got to seeing some photos of the new Porsche, Audi, and rumours about the Toyota laptime improvement I realized that the nissan program this year will be could just be fun and games (they way they went about the program has been great fun but, the competition appears to be on another level and it's too much to ask of Nissan as a first year program (Porsche atleast had recent prototype experience).

Bowlby may be eating words very quickly. He would only hope that his war of words pushed another competitor(s) into using a certain batch of titanium connecting rods.

[TME45]

Originally Posted by TF110

In terms of top speed, thats how I mean for it to "shine". Spa, Fuji, China, Le Mans are tracks where the concept of their's should show its potential (if it works).

I think Le Mans is the best place for them, this concept is not only talking about top speed, but low drag, it make better fuel consumption, it will have more advantage in a longer race, like the 24H.

[cokata]

Originally Posted by hcl123

Well i don't thing they will shine in top speed either.

Sure the car does seems to have the 'aeros' of a greater speeder, but:

If they opt as rumored for 2MJ, due to technical difficulties, it will be very weak on launching power for a petrol engine, simply not enough 'torque' for a petrol engine most specially at lower revs ( electric motors are unbeatable at torque... instantaneous torque... and all other contenders are 4Mj or higher)

Then there is the brakes... or their system is as good or better than Toyota's, in virtue of having smaller and less potent 'disc brakes', counting on the 'regenerative braking power' as an extraordinary auxiliary... or they will be faced with the need to start braking earlier after a long straight (exactly where top speeds are achieved), adding the fact of the front config, the balance must be very good and cornering speed also very high ( at the best) for this 'earlier braking need' not being exacerbated...

If they solve the technical difficulties of the hybrid system, and if they solve the *balance* issues of all the systems... they can be a contender... but i can't see that in 2015...

Engine torque alone is meaningless, what matters is the torque that reaches the wheels. Disels have more torque, but need to run longer gears than petrols. This is why we measure engine power in bhp or kw, torque alone doesn't give you the whole picture.

[pirenzo]

I'd love to see this work (mainly because I was a Panoz fan years ago and love the whole front engine thing) but it all looks a leap too far.

Lots of you seem to think that if not this year, then 2016 will be the year. I disagree. If the basic concept doesn't work this year, it won't work any year.

From what I understand, the design depends on this front aero through-tunnel business and a very powerful hybrid system to offset the loss of overall tire potential (created by the uneven weight distribution). So if these two systems don't deliver, they won't claw back the disadvantage of the weight/tire set-up, let alone gain something extra. Time will tell I guess...