APR Stage 1 Impressions

[Internexus]

That's an assumption at this point, we don't know what APR is doing, and I doubt they will tell us. But since people are also reporting improved gas mileage, it is improbable that they are simply "dump[ing] in more fuel".

Tuning fuel maps for heavy load WOT and cruising loads are two entirely different worlds...

 

[PRND[S]]

True. But engine temperature is going to be determined by partial load behavior unless you're at the track. Running fairly lean at partial load should result in higher engine and oil temperature, which is not what people are reporting.

 

[Internexus]

False, running a leaner air/fuel mixture at partial load will not yield the same higher temperatures under heavy load. The overall cylinder pressure is greatly reduced at lighter loads seeing as how there is negligible levels of boost being produced, and as I stated previously timing also plays a role in engine temperatures, advancing timing increases cylinder pressure and therefore would raise engine temperature.

This is all fairly standard tuning knowledge that can be demonstrated with even crude technology such as a carbureted V8 from the 60's let alone the finite engine management capabilities of today.

 

[Geomets]

The fuel actually play a coolant role in the combustion chamber. It absorbs heat, then (with the help of the spark plugs) ignite. Arin has said in another forum (I think) that their software tuned differently the cooling map of the engine (it is electronically controlled in the EA888 gen3)

 

[joema2]

That's an assumption at this point, we don't know what APR is doing, and I doubt they will tell us. But since people are also reporting improved gas mileage, it is improbable that they are simply "dump[ing] in more fuel".

They are absolutely adding more fuel. It is impossible to get major power increases without doing this. The energy for that power increase must come from somewhere. Gasoline has 114,000 BTUs (33,410 watt hours) per gallon. To get more mechanical power out, you have to add more chemical energy in.

They are not doing this all the time and may even have exploited other inefficiencies at part throttle to improve gas mileage. However in the area on the hp graph between stock and APR output, they are definitely adding more fuel.

Regarding reported gas mileage, if people are not manually calculating their mileage from gallons consumed vs miles covered, their numbers may not be accurate. The info system's indicated average mileage does not necessarily reflect real-world numbers, especially on a modified vehicle.

 

[Feralys]

I don't see how the onboard MPG will be inaccurate. They simply divide the amount of miles divided by gasoline consumed. I heard from SixSpeeder that his city MPG went down but highway MPG went up.

 

[PRND[S]]

The ECU has a very good idea of how much fuel is being used at any moment in time since it controls the amount of fuel going through each injector precisely. The only thing that would throw the MPG figure off is if the tire size changed and wasn't adjusted, but that shouldn't be an issue for anyone comparing their OEM vs. Stage 1 fuel consumption.

 

[Feralys]

The ECU has a very good idea of how much fuel is being used at any moment in time since it controls the amount of fuel going through each injector precisely. The only thing that would throw the MPG figure off is if the tire size changed and wasn't adjusted, but that shouldn't be an issue for anyone comparing their OEM vs. Stage 1 fuel consumption.

My thought process exactly. So another question I have is Multi-Port-Injection. I was looking at the differences between US and European models and it seems like we're missing that specific hardware. Then I looked into it some more, it seems like MPI helps prevent carbon build up on cars when idling or making small commutes... I fear we may have carbon build up issues.

And to be more relevant with the post's original question, I read some tuning articles and it made me even more confused how APR can get more MPG with just changing the Software side of things. http://www.fuelsaver-mpg.com/tuning-for-mileage

EDIT: Also.. I heard running lean ratios will increase car temperatures and lead to overheating of valves/melting pistons. I don't know, but most people that tune recommend running a richer ratio compared to lean ratios. If APR is getting more MPG by making the engine run "lean" then how come people are experiencing both increased MPG, significant increase in HP/Torque, and lower engine oil temps. Everything APR is claiming seems to go against the laws of physics to me, but then again there must be more than meets the eye(haha transformers quote). Arin or someone from APR, please chime in!

 

[Internexus]

My thought process exactly. So another question I have is Multi-Port-Injection. I was looking at the differences between US and European models and it seems like we're missing that specific hardware. Then I looked into it some more, it seems like MPI helps prevent carbon build up on cars when idling or making small commutes... I fear we may have carbon build up issues.

And to be more relevant with the post's original question, I read some tuning articles and it made me even more confused how APR can get more MPG with just changing the Software side of things. http://www.fuelsaver-mpg.com/tuning-for-mileage

EDIT: Also.. I heard running lean ratios will increase car temperatures and lead to overheating of valves/melting pistons. I don't know, but most people that tune recommend running a richer ratio compared to lean ratios. If APR is getting more MPG by making the engine run "lean" then how come people are experiencing both increased MPG, significant increase in HP/Torque, and lower engine oil temps. Everything APR is claiming seems to go against the laws of physics to me, but then again there must be more than meets the eye(haha transformers quote). Arin or someone from APR, please chime in!

Carbon buildup isn't something that is going to happen overnight, nor should it become of any significance below 100,000 miles either. Have you ever seen the carbon buildup on performance engines with 150k? It's negligible at best.

Your question of how they are tuning for gas mileage vs not blowing the motor is something I answered above. Think of your engine, now think of the load on the engine on a scale of 0%-100%. With the 0% being off and 100% being wide open throttle. What you are reading of melting pistons and running a tad more rich is when you are at 100%, when you are cruising on the highway you maybe at 35% load. That means that the strain on the engine is significantly less than what's occurring at 100% and you can run leaner fuel mixtures because of this.

There are countless articles and forum posts (not on this forum) on engine management tuning on the internet and there are also books you can look into. Both of them are great ways to help wrap your mind around what is going on with a motor and how you can tune to your own needs. Furthermore you can take your new found knowledge, download engine management software like AEM's EMS for example (http://aemelectronics.com/files/software/AEMPro_3.23R9.exe) and pick a random vehicles startup map and start dinking around with it. You will blow your own mind with confusion and just how in depth engine management truly is, google is your friend!

 

[joema2]

I don't see how the onboard MPG will be inaccurate. They simply divide the amount of miles divided by gasoline consumed. I heard from SixSpeeder that his city MPG went down but highway MPG went up.

If you manually divide your miles driven by fill-up gallons, you may see a significant difference vs what the car reports. Just today I made a long highway trip and the car reported 31.1 mpg, whereas the actual true mpg was 29.7. Other times I have seen a 3 mpg difference.

It seems after APR stage 1 the car's estimated mileage is optimistically high vs the actual real-world mileage. I have seen that same effect on previous cars with ECU tuning.

 

[Capkapak]

Does anyone have further updates on the 1st into 2nd gear jerks considering the DSG issues we've been hearing on the DQ200 although the GTI has the DQ250?

 

[joema2]

I experienced no 1st to 2nd gear jerks in my Mk7 GTI when stock, and none when on APR stage 1. *After* shifting into 2nd, APR reduces torque limiting. Combined with increasing rpm and turbo boost, that can produce a surge of power, but it's not a jerk when shifting.

 

[Arin@APR]

My thought process exactly. So another question I have is Multi-Port-Injection. I was looking at the differences between US and European models and it seems like we're missing that specific hardware. Then I looked into it some more, it seems like MPI helps prevent carbon build up on cars when idling or making small commutes... I fear we may have carbon build up issues.

And to be more relevant with the post's original question, I read some tuning articles and it made me even more confused how APR can get more MPG with just changing the Software side of things. http://www.fuelsaver-mpg.com/tuning-for-mileage

EDIT: Also.. I heard running lean ratios will increase car temperatures and lead to overheating of valves/melting pistons. I don't know, but most people that tune recommend running a richer ratio compared to lean ratios. If APR is getting more MPG by making the engine run "lean" then how come people are experiencing both increased MPG, significant increase in HP/Torque, and lower engine oil temps. Everything APR is claiming seems to go against the laws of physics to me, but then again there must be more than meets the eye(haha transformers quote). Arin or someone from APR, please chime in!

There's a couple way to get better MPGs. At cruise we can increase ignition advance to make more power with less fuel. We can also alter the air fuel ratio. The factory runs really lean and hot for most of the time at lambda 1. This uses little fuel, but when it gets too hot (usually quickly) it jumps to a really rich air fuel ratio to cool it down and in doing so, it uses a lot of fuel. We took a different approach which results in more power without getting so hot.

 

[Craigy1]

Iv had revo stage 1 on my mk7 gti for week or so and it's crazy ! Way more power and dsg gear changes are like they were before. There is a lot more wheel spin from 1 st to 4th gear especially in wet conditions. 320 bhp Approx and is a must for any gti owner and is well worth the money.

 

[GoTime1]

Iv had revo stage 1 on my mk7 gti for week or so and it's crazy ! Way more power and dsg gear changes are like they were before. There is a lot more wheel spin from 1 st to 4th gear especially in wet conditions. 320 bhp Approx and is a must for any gti owner and is well worth the money.

To be fair a stock car would spin in 4th gear through wet conditions.
Dyno your car please. Would love to see the revo graph