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Look I found my dyno from my emergency pump gas tune. This is on a Junkyard 1995 VW golf 2l 8v engine(a $105 junk yard engine). It has very little low end timing and this was with about 10 dyno pulls. This engine has 115hp at the crankshaft and in this dyno it made over 300 hp at the wheels. This engine would last a looooong time like this.

Yes obviously.
But without a proper stand alone TUNABLE engine management system, it would just run stupid rich everywhere with much larger injectors.

What some here seem to be claiming, is a stock late model engine can be doubled in power by doing nothing else except bolting on a turbo.
Good luck with that.

????

I don't think anyone on this list would think that. Now I'm on a couple of others where they do.

Actually you can buy kits for the 8v VW engine thats in my rabbit that increase by 150%. It does come with bigger injectors and a chip that remaps the ecu.

That is almost a three and a half times increase in torque and power.
Say 115Hp flywheel to 396 Hp flywheel (1.2 x 300 RWHP)
So induction pressure rises from 1 atmosphere to only 2.36 atmospheres (20 psi boost)
An absolute pressure increases of x 2.36.

How do you explain a 3.44 air density density increase that would be required to do that ?
Even with an impossible 100% efficient intercooler you will still get only get a 2.36 density increase.
Sorry I don't believe you, the figures just don't add up.

Whatever that engine is on that dyno developing 300 Hp with 20 psi boost, it is not a boosted stock 115Hp VW engine.

Far too many guys claim vast power increases without figuring the rpm, and air density, and fuel flow required to do it.

It is not difficult to spot the fakes, so don't even bother to try.

The car is my car. It did.You can believe whatever you want to believe but this is done every day.Here is my timeslip.

Sorry, I still don't believe a three and a half times power increase from a completely dead stock factory engine at stock RPM.

The trouble with turbocharged engines that make lots more power than stock is that they come on boost quite quickly ..meaning they rev faster..so in a very light car that is so much more apparent ,meaning it can be a handful to drive ,especially when grip is at a minimum.Im a huge fan of turbo cars but for me it needs to be 4wd and have sticky rubber or really your just going to spin the wheels .Now i know you guys are going to say that boost can be controlled but in the real world as it increases you need to decrease throttle ,or like i say it wheelspins,ive gone with the all alloy 2007 vq35hr engine from a 350z as it makes 306 hp stock and revs to 7500 ,it has variable cam timing on both intake and exaust and weighs 320lbs .The reason i went with this is that to get a 4cyl engine to do all and have a very flat torque curve would cost moonbeams,im not marketing for nissan im just explaining the benefits of modern technology that can be fitted to a 7 and be very easy to drive,and not require anything more than the stock ecu ,it will also take a beating for a good 150 000 miles ,also look at the weight of turbo engines with all the add ons and the fact that you need to squeeze all that into a very small car.I paid $1500 for a rolled over 48000 mile car ,it was missing alot of stuff that the owner parted out but i got the engine, 6 speed transmission,rear suspension with viscious lsd ,fuel tank ..i will use the stock pump ,ecu,all the wiring,master clutch and brake cylinders and lots more misc bits ,id look around at whats available .I see on your dyno graph that in the space of 2500 rpm you tripled the power ,that type of increase would be un driveable in a 7 .
wayne-o

Its all about what a engine is designed to do from the factory and how close you can push them to the knock threshold. The 115 hp is made to keep granny happy. The engine in question for instance has very short piston skirts (this is ultimately the death of these engines under boost as well). If you increase the timing advance they start to make alot of noise with the piston skirts slapping the piston walls. They also make another 8-10hp. From the factory they are also designed to be able to run on whatever you put in the tank.

There is only one thing that matters and thats the knock threshold. The closer you get to that the more power you make. If you go past it you make less power (or worse). My system was well designed and it shows in the output on the dyno and the track.The turbo is fairly large and is efficient at the boost pressures im running and the power level I am at. A smaller turbo would introduce more heat into the combustion chamber at the same boost level and this would lower the knock threshold as well as have less density (because its heated). This is why most stock small displacement 1.8-2l engines make between 200 and 300hp. As the story goes the ones with the larger turbos make more power. I have a larger turbo then they do so I make more power.

The stock compression ratio on my engine is 10-1. Most of the new turbo cars have compression ratios of between 9.5-1 and 10.5-1. This has to do with more engine management capability (starting to see a trend here). It is all in the tune. And just FYI,that 303whp on my car was a quick tune and the bottom end sucks because of this. It needs timing badly under 3000rpm.

This is true but,again engine management comes to the rescue. My engine management also controls my boost pressure (power level) and can be programmed to apply it however I choose to do so. My system right now runs a maximum boost in each gear and will run different percentages of the maximum boost by throttle position. There are many different boost control schemes to do other things as well but what I am doing is very similar to what the newer Audis,and EVOs do with their factory management (yes I also have anti-lag launch control ).

Please explain this then.

As shown on the above dyno sheet, that engine makes about 110 Hp RWHP at only 3,200 rpm with zero boost.

Yet you claim that engine is factory rated at 115 flywheel Hp, absolutely flat out, dead stock normally aspirated.

Are you saying that the original factory four cylinder engine peaks out at only 3,200 rpm ???

I still don't believe what you are trying to claim here, the numbers just don't make any sense.

Modern engine management is a wondrous thing, but it still cannot defy physics or thermodynamics.

To increase power by three and a half times takes three and a half times the airflow. Increasing the induction pressure by two and a half times will not increase airflow three and a half times.

I can tell you for sure, the pressure required to flow air through anything, including a cylinder head, goes up SQUARE LAW. Doubling the flow, requires a differential pressure increase of four times.

A three and a half times increase of airflow requires a pressure increase of 3.5 x 3.5 = 12.25

To do that requires eleven point two atmospheres of boost or 164 psi of boost WITH NO TEMPERATURE INCREASE.

Good luck doing that with a 10:1 compression ratio on a gasoline engine.

Zero boost is more then a stock car can have at any RPM. I would expect more power at that point. Boost pressure is not exclusive to the mass of the air in the chamber

So what you are saying is that a n/a engine has to rev to approximately double to flow as much air as a turbo engine at zero boost to flow the same ???

So the n/a engine must have about only half atmospheric pressure available at full power ?
So max volumetric efficiency of an n/a engine flat out can never exceed 50%

What utter nonsense.

Im not going to argue with you about something that is done every day. Im not sure where your from but this is very common where I live. High HP small displacement engines are all over the place here.

Now. A boosted engine will always make more power (0 psi is boost).

So explain to me in slow detail exactly why a normally aspirated engine with atmospheric pressure in the induction, makes a whole lot less power than a turbo engine with atmospheric pressure in the induction.

You are talking total rubbish.