Dyno results : please show yours !

[French Frie]

Here we are... we've discussed several time about stock outputs of the supercharged 3.5, and few seem to be surprised by the rumor that it is said to produce less than the official 345hp (din), but rather from 320 to 330hp, depending on  .

So, I think it would be useful to collect and gather all the dyno tests, with stock of modified engines, on Exige V6 (or Evora S S1), just to compare and know what we're talking about, as honestly as possible  ...

This not a matter of showing who's got the biggest , and I know there may be some differences between rolling roads, but it is a good start to talk about real figures, and also to know what upgrades offer !

So, as promised,  I tested my car yesterday, and will do it again, on the same rolling road, when the EX370 kit will be fitted... I chose to use an independant workshop (ie not the one that will fit the kit), that way it has no interest in proving the upgrade is worthwhile . 

The rolling road used was a Cartec (from a Snap On division), able to manage 4wd and up to 1200hp, so it should be ok  ... outside temp was 7°c, pressure was 1009mBar (those two factors are corrected by the Din norm to 20°c and 1015mBar). After fighting a bit to attach the car, they started to center the car and heating a bit the tires by rolling the car gently on the dyno... DPM was in OFF mode, and IPS in Manual. 

They struggled a bit as tires were still too cold and were slippering a bit on rollers, then they started a run "for real", in 5th... but at the top of range, the car hit the roadster's speed limiter  ! I 've forgotten to tell them about this 233 kph limit ... to be honest, that was the first time it was reached on my car, because even on the Hunaudieres during Le Mans Classic, I only reach 230 kph (on speedo) !

another run in 4th, with same parameters... I was a bit anxious, having told to the guy that I was expecting between 320 and 325 hp, but wasn't sure about how the IPS would reduce the output ! He answered he was quite confident it will reach this target, at least, by looking how the car was running... then the result came : 307 hp at the wheels, and 335 at the flywheel, transmission losses calculated  by braking the rollers when idling down ! Corrected , it makes 329,3 hp... so once again, we're in the often verified zone of 320/330hp, helped here by a quite cold weather (even if corrected by the dyno)!

what is interesting is that it is now a good start to see how it will be improved by tuning. I hope the EX370 kit can be fitted this week, and then it will dynoed once again. The other point is that he told me that the flat curve after 6000 rpm is not "normal", and may be related to ECU or TCU control, and that result could have been better if the curve has continued... please remember IPS cars are limited to 6750 rpm. Transmission losses are also quite low, which is a good news regarding the automatic and its converter (giving some high losses is often a "trick" for tuners to improve the flywheel numbers) !

I think it would be a good idea to add to this post all the other dyno result we can find, to settle a library... I found by searching on the forum that @Freejack dynoed his LF1 once, and found 330hp as well...

 

 

[Bravo73]

MY11 Evora S.

The blue line is stock. 316FHP.

The red and orange lines are with a KT switchable backbox fitted (valve open & valve closed). 318FHP. 

[TheKevlarKid]

Swindon tuned engine from GTE

[French Frie]

Edit : Freejack numbers were exactly 332 hp and 383 Nm  ...

Another dyno chart, from a friend of mine... stock engine, and always the 330hp barrier  :

 

[NW76]

I have to dig out mine ... will be interesting to see where you are after the EX370 Kit is installed ...

[French Frie]

You want my guesstimate ? It will give the 25 more hp claimed by KT, so I'll end (I hope !) around 350/355hp, which is my goal, just to have to official output I've paid for  ! Maybe a bit more if we can break this 6,000 rpm flat curve, maybe a bit less if TCU assumes  there's already enough torque for the gearbox... anyway, I let you know  !

 

Edited January 15, 2017 by French Frie
Spelling

[NW76]

Your flat curve looks strange ... almost like it's limited electronically... mine definitely didn't look flat ...

[NW76]

So - found mine:

1) After EX460 Upgrade:

 

2) Before and after in 1 Chart (the lower lines same color are before):

[Seriouslylotus]

I am no expert on rolling road etc et however there is something fundamentally wrong with the data being posted gents.

We have some graphs here from fundamentally the same engine but the cross over between torque and horse power are varied to say the least

Should they not all be similar????

Look at the graphs and see what I mean

we have cross over points of  about 3750rpm, 4200rpm, 5250rpm 5600rpm and 6800 rpm.

Something isn't right IMHO.

Any one have the experience and skills to explain why they are so very very different even taking into consideration the higher powered variants I would expect the cross over points to be similar not wildly different.

 

Answering my own question.....

 

It looks to me like its the scaling along the torque side of the graph!!!!!!!!!

Edited January 15, 2017 by Seriouslylotus

[French Frie]

@Seriouslylotus: yes it depends on the scale used, as well as the units used for torque ... to my knowlege, when exprimed in lbs/ft, the lines between torque and power should cross at 5250 rpm, IIRC, as power is the product of torque x rpm/5252... not the same for Nm, of course !

Edit : found the formula for torque in lb/in and for Nm : 

Power (HP) = Torque (lb.in) x Speed (RPM) / 63,025

Power (kW) = Torque (N.m) x Speed (RPM) / 9.5488

and 1 hp = 0.745699872 kW

 

 

[550superfast]

French Frie. Great thread, well done for starting.

I see from your chart your bhp is down from the Lotus claim, as you rightly observe. But if I read correctly your torque is actually up isn't it?

Lotus claim 295 lb/ft or 400NM. Yet you make 423NM or 312 lb/ft.

I think the torque needs to be discussed as well as the bhp figure.

[French Frie]

@550superfast: thanks Gary... it's faster to read than to write, when it's not your mother tongue  ! You're right about torque a bit higher than expected... and I assume that if it could be obtained to a higher rpm, it would have made more hp, regarding the relation between the two ! But it's not the first time I see a bit higher torque than specs, but less hp at the end... when Sport Auto (french mag) tests cars, it happens quite often ! It is a pity IPS is rpm limited ....

PS: i also think that higher torque may be the explaination vs the flat curve above 6K rpm ... TCU may regulate torque ! But we asked for his thoughts to Mr Komo-tec... let's see what he thinks about that !

Edited January 15, 2017 by French Frie

[geartox]

Very interesting topic. I should do this test. how much did you pay ?

[NW76]

I think it's around 150 EURs @ KT ... but I negotiated mine as part of the whole deal ... 

[French Frie]

@geartox: merci, Nicolas  ... in France, you should expect to pay between 100 and 150€ for a dyno test.

[NW76]

Just be carefull where you go ... you need a Dyno that also turns the front wheels, else you can forget the results, as the electronics will kick in even on DPM all off ...

[550superfast]

How so Norbert? The car is RWD, one click past Race disables everything.

What odd results would be seen and why?

[French Frie]

My experience differs ... the rolling road was a 4wheels one indeed, but front wheels didn't turn, and in DPM's OFF mode, it hasn't disturb anything, but as announced by the dyno guy, only turned the ABS tell light on  (which came off after few meters on "real" road) ...

[NW76]

Give KT a call ... if the front wheels dont turn you get the wrong results imho ... 20-30 Hps less ? ... seriously, I talked about it with Daniel when my car was on the Dyno and he even knew the figure of what it will have as a negative influence on measurement ... dont know anymore ... if it was 30 Hps though 

19 minutes ago, 550superfast said:

How so Norbert? The car is RWD, one click past Race disables everything.

What odd results would be seen and why?

There is a good explanation for it ... I just dont remember exactly what it was ... talked about it with Daniel from KT ... as he brought it up as one of the main reasons for wrong measurements with Lotus ... think it was electronics interfering even when all is off ...

[French Frie]

cool ! so my car is doing 360hp stock  ?? ok, thanks Norbert,  I'll have a check about that point ...

[550superfast]

I am not going to phone komotec to ask, you posted it up - just asking what the logic or reasoning is.

[NW76]

Sorry guys ... I do not exactly remember ... I just asked why the front wheels are even spinning, as it is a rear wheel drive car and then got the explanation...

[Bibs]

The Evora I took to a RR had the same issue. With the rear wheels at 170mph and the front wheels at 0mph the car had a real issue and limited the power, it thinks something terrible is happening! A powered RR which spins up the non-driven wheels was the answer.

[French Frie]

Norbert,  you're right  ! here's the (translated) answer of my workshop : 

"Bonjour Olivier, Oui. C'est vrai. Si les roues avants ne tournent pas, ça met le binôme ABS/ETC en défaut. Et l'ECU passe en mode dégradé, enrichit à mort et coupe avant le régime maxi.

hello Olivier, that's true. if front wheel don't spin, it makes ABS/ETC faulty, and then ECU goes in default mode, richening the mixture and cutting before max RPM."

so it may be the answer to my 6000 rpm flat curve ?

we learn every day ...

[550superfast]

Very interesting. 

How fast do the fronts need to be spun at?