Chip Questions

[ozzycupra]

How do chips produce extra performance ie, HP etc (NA engines)?

One thing I'm a little concerned about is that some claim the same if not better fuel economy. If they are using less fuel then surely the engine is made to run leaner! To me this means hotter operating temps especially if running at high revs consistently.

Any info or views would be appreciated.

[max_torque]

Chips don't produce extra power on NA engines!

Once and engine is mapped to LBT and MBT or det limit thats that - assumming the original calibration is correct. maybe once you could get a small improvement by optimising the manufacturers cal, but these days with adaptives and active knock control the std cal will be as good as it gets.

BUT if you change something that increases (or decreases!) airflow into the engine then you will need to reoptimise the calibration to suit. So a chip may allow other mod such as exhaust /airfilter to add power

The only time i have heard of any real power gains is when marketing have been involved, ie BMW 325 and 323, same 2.5 litre engine, 323 is detuned in calibration, hence fitting a 2.5 ecu or chip releases 25 bhp! (or buy an Bentely Arnarge Red label for £150k and buy a Black label ecu for £500 and save £38k! on the extra 60bhp!)

[Cupramax]

I would have to disagree. The gains wont be anywhere near as big as a turbo's car but there are gains to be had. From the factory cars are setup for so many environmental factors that there are bound to be some improvements to be made at the detrement to economy.

Look at Amd's site for example. Although they specialise in forced induction systems they also manage to get improvements on normally aspirated cars.

These two for example.....

http://www.auto-amd.com/mk38.asp
http://www.auto-amd.com/mk316.asp

[max_torque]

What are the improvememts measured on?

My dyno cell at work cost over £1 million, controls all temps and pressures to better than 1kpa and 1 degK, is calibrated every week, and i use iso 1585 correction factor (Uk homologation std for NA engines) and i only quote power to + or - 2%) (3bhp out of 150 bhp)

(on our chassis rolls (£5 million climatically controlled) i use + or - 5% after 10 tests for repeatability and 10% for a one off)

So it makes me laugh when people claim improvements of 1 or 2 or 3 bhp!

I would love to see a series of vehicle accels under controlled conditions with industry standard measurement (ie Datron, or Vbox etc) for a NA car run std then chipped - you will find you are wasting your money!)

[Cupramax]

Originally posted by max_torque
What are the improvememts measured on?



Their 4wd rolling road....

[max_torque]

We'll be generous then and call that + or - 5% at the wheels and say + or - 10% at the flyheel then.

which is 15bhp on a 150bhp car, rather more than the improvement a chip would demonstate on an na engine.

QED.

[Cupramax]

I'll let you argue that with them then, false claims and all that....

[Cupramax]

Just looking back through the thread I think you may have closed your own argument somewhat re the BMW 323/325 cenario. What proof have you got that manufacturers dont detune their cars for emisions/economy reasons? hence allowing tuning companies to modify these parameters for a more performance orientated tune.

[max_torque]

My proof is the fact that i'm the guy that does the manufactures calibration!

(i'm a senior calibration engineer at Prodrive currently having spent last 6 years at Cosworth, and i've cal'd a lot of cars from MGF's to Astons to Bentleys, VW's Audis)

Old cars are certainly easier to find gains on - as they didn't have the current level of intelegent ECU's so there had to be a "safety" margin left on spark timing and fuelling to account for all production tollerances - this is no longer the case with adaptive systems)

[Cupramax]

Calm down,...:flame: Your not the only person who knows anything about cars. I'm not questioning what you do or what you know. The examples I gave were of older cars i.e. 10 year old technology.

[ibizacupra]

There is an element of de-tuning as exhibited by the New Mini and its Cooper version. Only a software revision away from Cooper Power from a Mini One I understand. Serially programmed also... no opening up of the ECU to upgrade.

Bill

[ozzycupra]

Take a look at this data sheet. For a 1999 16V GTI Cuprasport. How can one believe a 16kw increase?

Datasheet for Seat Ibiza 16V GTI Cuprasport (http://www.powerchipgroup.com/gfx/datasheets/Sea0004.pdf)

I can't believe that the engine is that detuned to allow for a possible increase of 16kw.

Maybe they are considering that if you modify your airbox with a K&N replacement filter or kit, exhaust and the use of 98RON fuel exclusively AND with their chip you will gain the 16kw.

Anyway, would be interested what you have to say about it.

Thanks

[Wilko]

Max-torque.
I would say that you are probably right, but if a N/A car is recalibrated after breathing modifications, and optimised for 98ron fuel then some gains should be possible.
There are also some N/A cars that are detuned (software). Rover do 3 different power versions of there V6 2.5l in various MG's. Are you trying to tell me that this is more than software changes?
VW offer 150 and 180HP versions of the 1.8T which are purely software changes. OK they're turbo's but this adds weight to the marketing argument.
Some N/A engines are noticably lower in power than others of similar capacity. Most 2.0L engines produced 135-140HP and similar torque figures. Recently manufacturers have been producing 2.0l engines with 170HP by improving breathing at higher revs. The Torque has been improved slightly, but as you know this is limited by engine size. VW group produce a 2.0l engine with 115HP (125lb/ft). This fits into their engine range between the 1.6 and 1.8T. Are you argueing that VW have built an old fashioned engine with crap breathing etc, or is it more likely that it is software restricted. In the passat the same engine produces 130HP.
I agree that acceleration runs are more accurate than RR's, but on the same RR on the same day improvements of 20HP at the wheels have been seen on a simple rechip of this vw engine. Owners also say the car feele noticably faster (as you would expect).
Basicly the gains to be had without other modifications are minimal (as you say). But there are instances where manufacturers limit certain engines for marketing reasons

[Dormouse]

Hmmm...

I always thought that factory engines were slightly detuned for crapo eastern bloc stylee fuel etc.

I also thought that factory cars were designed to run quitely, smoothly and fuel efficently across the whole rev range (as far as possible at higher revs)

for these two reasons I believe that there is always room for a bit of remapping to move the power bands and fuel injection timings. not alot i'll grant. I recon in the realms of 5-7% is a good baseline figure.

Dor.

[ibizacupra]

Consider this input.

How many years ago did 1.4 engines produce around 60bhp or so from a good motor.

These days we see in excess of 100bhp.

The major difference?

Modern engine management systems.
Making the most of what you get.

(emissions tests would be the most restricitve element for car manufacturers on their quest for power vs ecconomy vs emissions etc etc)

regards
Bill

[RichardBW]

Just to give an example to keep the argument going.
The 1.4 Arosa for instance has a 75 and a 100bhp version. Same basic engine with different cams and software giving the different states of tune.

To try and tune a standard 75bhp with software alone is a complete waste of time. We have tried;)

[Cupramax]

Hi Richard.

Would be interested to see what mines putting out now as its loosened up quiet a bit. The power seems to come in a lot quicker now. Time for some decent tyres v soon as these P Zero's are crap! They seem to be very poor traction wise even in the dry.

[mark sheerin]

Car ECU's are ,I have heard ,specifically tuned to provide the best mpg and noise and emmisions for govt tests...therefore by ignoring the need to meet these criteria aftermarket allows more performance from the engine even in it wastes more fuel or makes more emmissions.

[edc]

Originally posted by GtiT

VW offer 150 and 180HP versions of the 1.8T which are purely software changes. OK they're turbo's but this adds weight to the marketing argument.

Is it only a software change? No upping of the boost, bigger turbo, larger manifold, different fueling, different internals...?

Originally posted by GtiT

Recently manufacturers have been producing 2.0l engines with 170HP by improving breathing at higher revs. The Torque has been improved slightly, but as you know this is limited by engine size. VW group produce a 2.0l engine with 115HP (125lb/ft). This fits into their engine range between the 1.6 and 1.8T. Are you argueing that VW have built an old fashioned engine with crap breathing etc, or is it more likely that it is software restricted. In the passat the same engine produces 130HP.

Modern engines have more bits and bobs (technical term) than their older counterparts. VVT etc etc, you'd expet improvement with all the R&D thta's done wouldn't you?

The 2.0 engine is quite old in comparison to the 1.8T, they didn't build it crap, it's just they could make the 1.8T 'better'. Howis it my 2.0 manages 150bhp (allegedly)?

[mark sheerin]

The 2.0 litre vw engine 115bhp is 8v the passat is 16v.

the 8v is a long stroke motor

the 16v is short stroke.

long strokes produce more torque


short strokes are able to rev faster.

generally a shorter stroke motor will produce more bhp because its high revving ability will allow shorter gearing and therefore give more mechanical advantage.

[max_torque]

"Car ECU's are ,I have heard ,specifically tuned to provide the best mpg and noise and emmisions for govt tests...therefore by ignoring the need to meet these criteria aftermarket allows more performance from the engine even in it wastes more fuel or makes more emmissions"

That maybe true, but the emmsions area in terms of engine speed and load is nowhere near the full load line. A typical road load model for emmisions testing will only require the dyno to absorb 7kW at a steady 70mph. not very close to max performance for a modern 100Kw or more engine!

What this means is you can calibrate an engine to perform well both for emmsions and for power. In fact many emmisions improving factors also help power, ie, high compression ratio, low friction, high engine volumetric efficency etc.

When we calibrate a new engine, it will spend maybe 6 to 10 months on an engine dyno doing base mapping for power and emmsions. We will optimise everything (inc varriable cam timing, torque reserve, varriable intake, fuelling ignition, knock control the works!)

BUT at WOT it will be running the best fueling for max power and an igniton timing within 2% of detonation / MBT (systems without knock control) or MBT / det limit for knock controlled systems.

Engines with a long stroke produce good torque at low speed because the longer crank stroke produces a greater turning moment when the piston is halfway down the bore, more leverage if you like. However this long stroke increases maximum piston speed (and accel) as piston has to travel further in a given time. For durability issues this limits max engine speed, and for any given capacity engine the longer the stroke the smaller the bore, hence the smaller the valves, limiting peak airflow and power. These factors are reversed for a short stroke engine. As power is effectlively Torque times Speed the faster you can rev the more power you make.

[Dormouse]

How many years ago did 1.4 engines produce around 60bhp or so from a good motor.

These days we see in excess of 100bhp.

The major difference?

Umnnnn an extra 8 valves?

Dor.