G100extreme

Yes its true... Why don't ask, but I'm into the electronics... I'm looking for a 096 with a length of loom (+ connectors) and the TCM if anyone has one- ideally for a 4cyl block, although I could hack the VR6 bellhousing off... I've come up with a whacky way of overiding the lockup feature between gearchanges, which in effect gives you a really fast launch. Way faster than with a manual. I've done some expirements already in another car, so now I just need the hardware. Anyone got a spare 096 going? Doesn't have to work, so long as it hasn't been completely 'lunched'. You name the price...! cheers, frank

About 1.005kJ/kgK @20 degrees C (293K) I'm doubtful wether this would work. Peltiers drain a pretty large amount of power. when used to cool cpu chips 300W is not uncommon. I suspect you'd need a pretty large device to cool the volume of air we're talking about here, to the point where the power drain renders your efforts pointless. I am surprised to hear they use them on aircraft though. Perhaps here the available power outputs make it more worthwhile, as the fractioanl power drain is almost negligeable? It takes a (admittedly relatively small) Peltier about 30mins to temperature stabilise a diode laser to around 17C (so only around a +5C temperature gradient) in ambient conditions, so I don't think a system whereby you activate the Peltier only at WOT would be that effective either. I dunno. Colling chips is very different to cooling engines! Thnx big ted. So if the mass of 1L of air at ambient is about 1g, 1500L works out at 1.5kg. Mmmm, ok so I guess that is about 1500W per minute. Yup that wont work... and that's to drop the temp by just a single degree. Dropping it by say 30C would be lots... I guess using liquid nitrogen may be more effective... :shock: I guess this shows how much energy is released when you burn all the fuel. Its only when you convert from HP to kW, you start to appreciate how much power it takes to move a car... -frank

Ah yes those were the days.... That was when an engine had to produce power. The best we ever managed from a 1.5L N/A (Fiat engine) was about 200... but with lots of mods (and lots of blown headgaskets). And that was at about 7500RPM. Those old 1.5 F1 engines used to rev up to about 25k didn't they. It was the old problem of having too large a combustion chamber for the burn time available. Micheal May from Jaguar solved that one back in the 80's. Smaller chambers, higher compression with the chmaber just under the exhaust valves. Mind you I guess its obvious really- thats why you now get 2.5L V8s. Smaller pots, lower burn time, higher revs, more power... Half a litre cylinders are now considered too large to burn quickly/completely at 6000 RPM. I guess the old aero style engines with twin plugs is possible. I never studied what happens when two flame fronts "collide"... Actually there's that new style plug that has gas jets built in, to distribute the flame more evenly. Dunno much about them though. -f

well, although the 4cyl VW/audi bottom end is pretty much bullet proof the 16v head is not a masterpiece for performance, although it is generally acknowledged that you can get 170bhp from an ABF (mk3 16v) quite easily without wild cams or major headwork. I think the minor improvements over the 6A/9A Corrado/Passat/Audi 80 2.0 16v plus the fully electronic fuel injection does produce a good improvement. The golf G60 Limited was an 1800 16v with a G60, but only 210bhp, difficult to get the G60 charger to last very long at the higher revs it needs to spin to get more power than that and the charger is just not really big enough for larger engines. David. I guess that's why you'd need a G100 or similar :D -frank PS, I wonder what is the theoretical limit you could get out of a standard 2L block before it went pop... Anyone done any experiments with dynos out there? Perhaps 10kRPM and 500HP? Mmmm that would be interesting... You need 4WD and some very high gearing...

I hadn't heard about this... Is this true? Or did they just up the RPM to get the extra, or was it across the band? What is the difference mechanically? The basic 16V is a superb engine, which is why the 2L block is used in so many variations. If it is possible to get 170+ out of the standard normally aspirated engine, then with a G60, the power available would be obscene. I mean with such a lightweight engine, with all that power... Hang on didn't VW make a golf with that spec... :) but like only about 75 cars or something- worth quite a bit now... G60Jay, what are you running? A VR6 4motion system (chipped?)? -f

On the subjecto of charge cooling to increase usable oxygen to burn... I've been playing with one of those peltier (TEC) cooling devices- put 12V in, and you basically get cold out- no moving parts. I wonder how efficient it would be to get a stack of them, bolted to a large headsink, after the intercooler, and then chill down the air to really cold, like -10 or something... The specific heat capacity of air is fairly low, so i don't think the power demand would be that high- only a marginal load on the alternator (and I guess you could switch on only for WOT). If the density of the air could be increased by only say 10%, that would probably give an extra 10% more power... without doing the maths (similar to what they do on military aircraf jets engines). Ok, so at 6000 RPM at WOT, assuming no losses on a 4 cyl 2L engine, that would be 6000/60 is 100 per sec. For 4 stroke 100/2 =50 cylinder sucks per sec. Each cyl is 0.5L gives 50 X 0.5 is 25 litres of air a second (or X 60 1.5 cubic metres of air a minute.... Anyone know the specific heat capacity of air at normal pressure...? :lol: Thoughts anyone? -f

I've always found that when the air temp goes up (on a fuel injected car) the power drops. More space between all the air molecules means less molecules of air to burn for a measured volume of charge (hot air is less dense, which is why hot air balloons work). This usually means less power... Heard of an intercooler? its to get around that problem. :) frank

That graph doesn't make sense... :? At low RPMs, the two lines should almost meet if it is a real plot. Think about it... The only thing that should change is at the top end, with the curve being steeper between 2 and 4000 RPMs. uh! hang on a minute- what else has been done to this beast? The graph looks about right for a compressor forced induction engine, where the pulley was changed... or perhaps the exhaust tubes or cam dwell...? Let us into the secret. -frank

Whilst sipping on an iced glass of Bailey's... Merry Xmas to y'all. I have got to agree... It is true. Manufacturers do spend a fortune on getting the map just right for ALL power profiles. Putting in a box between a sensor and the ECU does basically change the position on the map. Think about the poor old engine designer for a sec. If you designed an engine, you would want it to run as well as you could possibly get. Just like when we modify our Corrados, we want the very best we can get out of the car. This means for economy, emissions, smoothness, and power. Marketing department want to be able to brag about the maximum power, whilst being really economical and clean, for the greenies out there. Lots of people make 2L 4 cylinder engines, so the power per litre is a good measuring stick to use. The average nowadays is about 67hp/L. That is the absolute maximum that the power plant can generate at WOT, given the cam profile is setup for low revs and regular driving. Each engine is designed to produce as much power as it is possibly is able to generate. If I didn't map an engine out to produce the maximum it could produce, I wouldn't be doing my job right... Do you see what I mean- It makes sense for a manufacturer to tune an engine to produce the highest possible power per litre. As to control emissions- use a big low restriction cat. Noise- a low restriction silencer, with resonance box and tuned pipes. Economy- select cam, compression ratio, combustion cylinder shape, timing profile, EGR, running temperature, mixture profile etc for every possible circumstance, at every RPM. Most ECUs now have over 1Mbyte/word worth of 16 or 32 bit memory locations (all filled) to cover every possible permutation of engine running condition. Think about it. Well over a million possible lookups for any sensor reading. Its mind blowing really. In that way engine manufacturers can guarantee max power for their engine. People keep going on about that mass produced engines are not really that precise, and by remapping an engine you get more power. Put it this way, the journals on your crank were mass produced to an accuracy of around 0.02mm. :shock: That is accurate- a hair is about ten times bigger. The particles of carbon and metal suspended in oil are the smallest part of your engine, which is why that oil needs to be kept clean. A car engine is a very precise machine. It never used to be though... which is why blueprinting used to be so popular. Production engineers take great pride in being able to mass produce a precision machine. They keep bragging about it, even to the extent VW TV ads are featuring men in white coats showing their obsession with how precise their little design works :) Isn't it just great! (ok so they usually wear blue coats...) -f

Did you have a "before" printout, so you can compare before and after...? The main reason remaps run smoother is because the ignition is usually retarded a bit and the mixture is richened up a tad. You'll find there wont be any power difference, but the excess fuel hanging around will mean there'll be no possible 'lean out' problems, making it feel like the engine responds faster when not being loaded up. It gives the impression there is more power... In hot weather you may even notice a loss in power. COld starting maybe easier in really cold conditions. What you need is one of those portable mixture analysers rigged up to your O2 (lambda) sensor, to measure the mix as it comes out of the engine. I guess most after market chips (haven't tested them) allow for more breathing mods, and richen up the mix to compensate. Saying that though, the difference is only really noticable at WOT, as the ECU will try and keep the mix just right at medium throttles using the feedback signal you get from the O2 sensor. The easiest way to avoid chipping the car and using the original engine designers map (where they spent over a billion doing it) is to fool the computer into thinking that the mixture is too lean, by placing a little black box between the O2 sensor output and the input to the ECU. You can get a normal, economy and power switch type that does more or less the same thing that re chipping achieves. It simply leans out, connects through or richens up the mix. -f

Yeah ok, (writing with a grin...) Back to the main subject again... so now you all understand why chipping a normal unmodified engine wont make any difference... :) Anyone from AMD like to comment? :wink: -frank (So I must be an engineer...)

Here are the answers you've been waiting for... Yes most people got them right! There must be some professionals on this board as one or two of those questions are not generally things that people will discover without a real engine dyno system, and experience in design engine/fuel management systems. I think we can all go out and buy ourselves a beer! 8) Answers after each question...

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

How the hell did G60Jay find the space to fit all that under the bonnet? I guess the PIC says it all. Can't beat that cross flow head. I now understand why some people go for 4WD. All that power through 2 wheels... yeah ok. Its a bit like the americans with their 5.7L V8's and then they just wheel spin all the way up to 100kph. (ok so they do have a lot of fun getting there...) 8) G60JAY, you get my vote just for the sheer audacity for attempting such a conversion. -f

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