Chipping a normal motor will make no difference...

[G100extreme 0]

Ok, I've been having this debate with someone about how if you take a factory standard lump and chip it, you wont get any more power. Ok so there are conditions. Keep the revs under 5000, and same air induction system, fuel and injectors. Basically change nothing except the chip.

 

Here's my theory...

 

The ECU will always try and keep a correct burn for a specific manifold plenum pressure, based on what it is seeing on the lambda sensor. If you run rich, you'll see marginally more power but say bye bye to any economy. If you mess with the ignition timing (assuming the fuel or compression ratio have been not changed), the knock sensor will simply retard the timing back to just below knock.

 

So in a nutshell, keeping the mixture stoiciometric, the fuel the same, and the induction pressure the same, there isn't much a chip can do to get any more power at low (normal) RPMs, at wide open throttle (WOT). Having the chip add more fuel at WOT wont achieve much, except poorer economy...

 

Ok, so if you go above the normal rev limiter, then of course it is possible to get more power, as there is more fuel/air throughput. But still it is only apparent if you are at WOT.

 

Am I completely mad, or does any of this make any sense??!?! :roll:

 

-frank

[exturbo2003 0]

on a standard engine:- knock sensor= back up protection

lambda sensor=reads oxygen in the exhaust

now on a modded chip you can program the ecu to use the knock sensor all the time rather then having limits of which the knock sensor will back up.

as for oxygen readings these wont change but how the map in the ecu responds can. they are mathamatical equations so all you have to do is chang the equation slightly.

you can still get good fuel econemy if its mapped well. some engines are better then others for this a s they have more sensors and you havent stated a particular engine.

manufacturers have to have econamy and emissions to deal with as wella as a broad range of fuels and a lot of times differant country's so a ron from 91 -97 where as a chip can specify a fuel to use ie 98 ron and be mapped to suit.

when my escort turbo was standard it returned 24 mpg average when it was chipped it made 28 average and 30bhp more :D

hope this gives you reason to debate

[samm_cvr6 0]

Surely it is more important what engine you are chipping? N/A are the least receptive to chipping and PD/Common rails with intercoolers are the most receptive. Like you say, I'm sure if you were running say an induction air filter with s/s exhaust or something similar, the benefits of a chip would be enhanced as you can get a faster flowing air thru the car.

[CoxyLaad 0]

also I dont think the ECU pays any attention to the lambda probe at WOT.

 

it only uses it at part throttle as part of its closed loop running cycle

[G100extreme 0]

To get more power, you need to push more volume through the engine... At WOT, the injectors are dumping just the right amount of fuel to give you max power (as set by the engineers at VDub). No new chip can make any difference to that!? (I'm assuming the ignition timing is just right for the fuel). You could almost say that at WOT, you have the equivalent of a diesel engine. The only thing that makes a difference is the amount of fuel and the moment it ignites.

 

A chip will not change the volume through the cylinders. That is limited by cylinder capacity and flow restrictions (at a particular RPM).

 

True- on a turbine or compressor assisted engine, the chip may allow higher boost at lower RPMs (if there is an electronically programmable wastegate or dump valve), which would give more power.

 

To get more power, either:

A) get a bigger engine (or increase its throughput capacity somehow, by boring, milling and flowing)

B) increase the RPMs (just like with F1 and motorbike motors)

or both :)

 

-frank

[Kevin Bacon 5]

Ring AmD and tell them all that then.... I would love to hear what they have to say about their £350 chipping servicing being a complete farce and a waste of time :lol:

[Scott 0]

To get more power, you need to push more volume through the engine... At WOT, the injectors are dumping just the right amount of fuel to give you max power (as set by the engineers at VDub). No new chip can make any difference to that!? (I'm assuming the ignition timing is just right for the fuel). You could almost say that at WOT, you have the equivalent of a diesel engine. The only thing that makes a difference is the amount of fuel and the moment it ignites.

 

A chip will not change the volume through the cylinders. That is limited by cylinder capacity and flow restrictions (at a particular RPM).

 

True- on a turbine or compressor assisted engine, the chip may allow higher boost at lower RPMs (if there is an electronically programmable wastegate or dump valve), which would give more power.

 

To get more power, either:

A) get a bigger engine (or increase its throughput capacity somehow, by boring, milling and flowing)

B) increase the RPMs (just like with F1 and motorbike motors)

or both :)

 

-frank

 

But your sticking to the basics - you are ignoring the fact that manufacturers design the chip for the engine on a mass produced basis. They also as mentioned have to factor mpg / emissions / etc to keep the general public happy and in some cases run a slighty detuned chip to ensure 100% reliability (eg diesels)... I have also known some manufactuers deliberately detune some engines to prevent them from showing up their flag ship models...

 

In most cases if not all - a chip designed for a specific engine by an aftermarket manufactuer with no other mods WILL gain 'some' power as although you are right in that the flow characteristics will not change but the ability of the aftermarket chip tuners is to maximise all values to develop more power.... even given the general scenerio that you wont gain much power from doing this without mods.

[dr_mat 0]

All possibly true. But then you have to ask - is it worth the money? It's quite time consuming and therefore expensive getting someone to chip your car. If all you gain is a tiny bit of driveability and maybe a couple of bhp for your three-four hundred notes, is it worth it? On a turbo engine you'll get big gains pretty much all the time, but on a N/A engine it's questionable whether it's worth it at all. IMHO not. I had to have mine done to protect the engine from lean running with the Schrick installed, but that's the only reason I would have considered it.

[davidwort 0]

Ring AmD and tell them all that then.... I would love to hear what they have to say about their £350 chipping servicing being a complete farce and a waste of time :lol:

 

interesting this, depends on the engine management system capability I guess, I'm sure my NA golf IV 16v would benefit, just from the throttle response alone (somtimes I wonder if it's ever going to pull away at roundabouts!), but that's an emissions friendly flly-by-wire throttle.

I've no doubt that you can get loads more from chipping a turbo, but on a lot of NA cars 350 quid may not get you much of an improvement as some systems are pretty good already and even adaptive to driving style. There's always going to be some room for improvement when considering a custom map, just don't think it's the first 350 quid I would spend on a car. I'd imagine you would need days of testing at different temperatures and atmospheric pressures to get a really accurate custom map, I think AMD and the like start with a basic 'performance' map and then just tweak bits of it to suit a particular car on the rollers, certainly better than an off the shelf ' performance' chip that is just substituting the manufacturers best compromise for someone elses guesswork, hence the overfuelling, pinking mess that quite a lot of people end up with.

 

David.

[dr_mat 0]

Interestingly, considering Kev's comment above, in a previous thread we've already heard that Vince@Stealth doesn't reckon it's worth chipping standard VRs. That does imply that AMD are taking your money for nowt... ;)

But then if you really want to spend money, no doubt any of the tuners will help you out. AMD will go that one step further and give you a RR print out showing an EXACTLY 10bhp performance increase which, interestingly, all comes from the "rolling resistance" calculation... :roll:

All my own opinion! ;)

[dr_mat 0]

** - But then I should point out that the VR has a pretty advanced engine management system, particularly compared to the 16v/G60 cars, so maybe there's more benefit to be had on the less advanced ECUs.

[samm_cvr6 0]

do AMD charge a standard rate for chipping all cars? I know superchips charge more for chipping turbos. Just wondering as if they do charge a standard rate then it would make it much more cost effective to chip a VR rather than a valver. I would probably make a chip my 3rd mod if I was going down that route after air filter and exhaust, makes more sense IMO. Turbos also seem to benefit more from air filters and exhausts. I've heard crazy figures like 40bhp increase with a full exhaust system on a Scoobie.

[Henny 0]

just to throw another log into this fire...

 

I'd NEVER buy a standard "off the shelf" map chip for an engine... EVERY engine is different, even those built by the same person at the same time... If I wanted to chip a car, I'd get a custom chip written on a rolling road so that you KNOW that the chip is spot on for your engine and is producing the optimum power from the components you have... Any other "off the shelf" chip is going to have too many compromises and assumptions in the map burnt into it... :twisted:

[dr_mat 0]

do AMD charge a standard rate for chipping all cars?

 

Turbos also seem to benefit more from air filters and exhausts. I've heard crazy figures like 40bhp increase with a full exhaust system on a Scoobie.

 

It's a different price for each car. They charge IIRC £350 + VAT to chip a VR. Not very "cost effective" if you ask me..

 

And the chipping game is completely different for forced induction. You get your money's worth with forced induction chips!

[beavis 0]

just to throw another log into this fire...

 

I'd NEVER buy a standard "off the shelf" map chip for an engine... EVERY engine is different, even those built by the same person at the same time... If I wanted to chip a car, I'd get a custom chip written on a rolling road so that you KNOW that the chip is spot on for your engine and is producing the optimum power from the components you have... Any other "off the shelf" chip is going to have too many compromises and assumptions in the map burnt into it... :twisted:

 

True.. to an extent. On the other hand I've seen a few car mapped by muppets who have mapped around inherent problems that a car has. e.g. weak fuel pump and compensated by running a crazy injector duty cycle.

Custom maps need to be created by a operator who is conversent with the mechanics of the car to be mapped and the car that is being mapped is 100% functional before being mapped.

A map is as good as the person producing it, off the shelf or custom.

Assumption is used in custom maps also. The only map that will be 100% true is the line that is being adjusted at the time of mapping, the operator will adjust igntion advance and fueling with the car running for arguments sake 92'c water temp, 25'c inlet air temp at all the different load points for say 5psi of boost, but alll the other values afterwards in real world will be assumed. He will dial in a % correction for water temp, air temp etc etc etc which throws the custom theroy completly outta the window unless they have manipulated and mimiced all synarios of possible running conditions that the engine will operate under in everyday use...

This thread could be one of those ..lol

[Joe M 0]

So really the best way to map a car would be to drive it about with the operator in the passenger seat with his laptop instead of on a rolling road?

[pablo_vr6 0]

I'd NEVER buy a standard "off the shelf" map chip for an engine...

 

time for another log ;)

 

I bought an off the shelf chip for my fiat coupe turbo. all it does it remove boost cut in 1st and raise the fuelling map to 1.4bar. pure off the shelf one size fits all :)

 

Was only £100 too

[Kevin Bacon 5]

I've heard crazy figures like 40bhp increase with a full exhaust system on a Scoobie.

 

That is true, but only on some Scoobies, because the standard exhaust front pipes are half the size of the exhaust header output, so therefore fitting a fully open front pipe is where the power comes from, not so much the chip. Although there are gains to be had there too.

[pablo_vr6 0]

doesnt chipping just Up the boost? hence more hp?

[G100extreme 0]

Time to ask some basic questions to gauge the level of knowledge here.

I just had to add some logs to the fire... :wink:

 

Why are there different ratings for fuel octane?

What effect does changing the compression ratio have?

What effect does increasing cam dwell and overlap have?

Why do you need to advance the ignition as the RPM increases?

Why is it that longer exhaust manifolds/headers/extractors (or whatever you want to call them) increase power?

Why does water/steam injection help generate up to 20% more power?

Why do most fuel injectors run at 1.5ms pulses at idle no matter how big the cubic capacity of the engine?

Why do carburettors generate more power than injectors?

What is the point of the variable inlet plenums on the new VW engines?

Why can you sometimes get more torque by delaying the ignition timing?

 

:lol:

 

-frank

[pablo_vr6 0]

the bloke down the pub didnt tell me any of that!!!! :shock:

[Dan_Storm 0]

My C is standard apart from a K&N panel filter and an AMD remap. There was a definate improvement in power, throttle response and driveability. Fuel consumption also improved.

 

AMD's figures showed a 15bhp increase which I'm sceptical of (as others are with AMD's figures), but either way the car pulls better.

 

Something I've been wondering recently is can another company remap an AMD chip? E.G. say I fit a Schrick could/would Stealth remap an AMD chip?

[Kevin Bacon 5]

Time to ask some basic questions to gauge the level of knowledge here.

I just had to add some logs to the fire... :wink:

 

OK Sir Lancelot I accept your duel.......

 

Why are there different ratings for fuel octane?

 

Do you mean Research Octane Number (RON) or the more relevant to car engines Petroleum Octane Number (PON)? Unfortunately PON isn't used over here, but anyway it is the fuel's resistance to knocking. NA Engines with high CRs and FI engines can maximise their potential with high octane fuel as they can use more ignition advance.

Lower octanes suit lower spec engines with low CRs.

 

What effect does changing the compression ratio have?

 

More "squish", more engery released from the burn, more torque.

 

What effect does increasing cam dwell and overlap have?

 

God knows. Too much overlap on a FI engine is a bad thing though as all the boost goes out of the exhaust valves before they've had a chance to close!

 

Why do you need to advance the ignition as the RPM increases?

 

As the crank speeds up, the timing needs to be altered in order to maintain the correct burn. Obviously a crank spinning at 7000 rpm will present the piston crown to the combustion area a lot faster than it would at idle. I think that's right....sounded good anyway :-P

 

Why is it that longer exhaust manifolds/headers/extractors (or whatever you want to call them) increase power?

 

Something to do with pulling the exhaust out of the combustion chambers, speeds up gasflow and all that.

 

Why does water/steam injection help generate up to 20% more power?

 

Cools in the inlet charge. Denser inlet charge = more power. Water also contains oxygen and Hydrogen, so therefore more oxygen & hydrogren with a pinch more fuel = more power.

 

Why do most fuel injectors run at 1.5ms pulses at idle no matter how big the cubic capacity of the engine?

 

Dunno. Nice round number?

 

Why do carburettors generate more power than injectors?

 

Because they're big bad Mofos and you can't beat a big old Holley carb sitting on a V8 :lol: But err, dunno. But carbs ice up though, so no good in the winter.

 

What is the point of the variable inlet plenums on the new VW engines?

 

Longer inlet tract = more low down torque, shorter inlet tract = more power at the top end.

 

Why can you sometimes get more torque by delaying the ignition timing?

 

Because you say so :lol:

[dr_mat 0]

Carbs pump in more fuel, end of story. That's why the increase in power. Another reason is an engine on carbs is generally running without catalysts, so the exhaust is more free flowing. Well, with all that overfuelling going on, the cat would die pretty quick anyway. It's no mistake that every car ever built with a catalyst has electronic fuel injection.

[CoxyLaad 0]

Why do you need to advance the ignition as the RPM increases?

 

As the crank speeds up, the timing needs to be altered in order to maintain the correct burn. Obviously a crank spinning at 7000 rpm will present the piston crown to the combustion area a lot faster than it would at idle. I think that's right....sounded good anyway :-P

 

 

Just to add to this, if you think of it all in slow motion, the cylinder rises slowwwwllllllly toward the top of the piston compressing the mixture, The spark plug fires splatooosh! (or what ever a spark plug firing noise makes). The mixture does not then explode instantaeneously but spreads from the plug out over. As the revs increase (vrroooom) the spark plug has to fire earlier inorder for the mixture to be fully burnt at the right time.

 

Make sense?

 

This also explains higher compression, mixture is squashed closer together therefore burns quicker.

 

yes! top scientific explanation there

 

I thank you :D