This is what a stage 2 1.4TSI truthfully makes

[chuckb]

Have to agree though, 6 posts, all in this thread and most are argumentative, is this what's known as a troll? Or is it someone else registered in a different name

Ah the game is afoot Watson!

Trollage!

 

[phil_monk31]

there is another JKM dyno day in August and I will attend again along with mOrk who will be there with his cupra. he has stage one with sps so we will be able to gauge a much more accurate reading on the power gains between stock, stage 1 and stage 2 IRRISPECTIVE of what the numbers say. it will be about the gains and this is really what myself and Sy are interested in.

Il be there mate

 

[vRSy]

as JC said and as i have said in many many posts. gains are what matters which is why i always say before and after runs are what people need to do. I specifically asked my tuner to do this for mine as i hate quoting figures without seeing the original curve. Its also why i got an indendant dyno result when stock prior to the map and have gone to JKM since the map to confirm. all the dyno results i have correspond as expected, so im 100% happy my car is running as i and my tuner expected.

Just want to point out this thread wasnt about revo bashing, it was highlighting how these two seperate tuners stage 2 maps were practically identical in performance, running well but running way off of the 'quoted 230hp'. I dont doubt if i was to head up the road to AMD or even better superchips id make a further 20hp easily. But hey ho, im not figure chasing.

You also have to be realistic as well. What matters is power to weight. Personally i think the performance of my car (213hp/1200kg=177.5hp/ton) marginally better than my octavia when i was running the stage 2 on there (262hp/1470kg= 178hp/ton), which sort of makes sense looking at the power to weight figures of both (figures both from JKM). The DSG probably helps to give it the advantage as well. but it isnt as quick (once rolling) as my stage 3 octavia vRS was (275hp/1470kg= 187hp/ton)

So just by basing it on the performance comparison to my last car i had estimated it to around the 210hp margin anyway

 

[dera]

Sorry i guess my english are bad, but when u say compressor u mean the actual compressor of the car or the propeller of the turbine? If you are reffering to the actuall compressor then it is disengaged after 3,5k rpm because the mechanical door closes at that point so the air is only coming in from the intake.

If you mention to the turbine how do u estimate the amount of rpm when you do not know the AFR, Advance, Ambient Temperature and so on? Even if you knew how many grams of air i have coming in you still wouldnt be able to give an good estimate of the cars power.

I disagree that the most efficient way to measure power is weight and terminal speed @ 1/4 mile. You do realise the amount of parameters (tyres, suspenions,wind, track). Imagine 2 identical cars, every single setting same apart from one having lets say a gearbox from a diesel car, the difference between these 2 cars would be atleast 3-4cars distance. Would you say the 2nd one has more power or it spreads the same power better and requires at least 1gear change less hence ending up faster.

I guess you are proffesional in tuning, so could you be more specific on what settings you run your remaps, AFR,Advance, Boost pressure, Abs throttle position(all the way to the limiter)

Just to clarify, I mean the compressor wheel of the turbocharger. That is the wheel that compresses intake air, and gets its power from the turbine wheel that is rotated by exhaust gasses.
You can think of it as a wing on airflow, where it creates high pressure and low pressure areas. It also has an angle of attack to the intake airflow, and when the angle of attack increases too much, the compressor stalls.
Very basic thing about aerodynamics and wings is that a wing always stalls at the same angle of attack. The angle of attack is dependant of the intake air mass/speed and compressors rotational speed. Thats why turbocharger manufacturers produce compressor maps.

Thats also why there's a limit of how much air a compressor wheel can produce, because eventually it will stall. You can have a very powerful N/A engine where the turbocharger does only harm, because the compressor is fully stalled just by the amount of air inhaled by the engine (well, that would mean you'd have a 12-litre marine diesel and a K03 but just to give you an idea what I mean).

I do not have to "estimate" the rpm, its actually mapped in the ECU by OEM engineers. There is a map in the ECU where its told how fast the turbocharger rotates at certain airflow and engine rpm. To achieve enough airflow to reach 230hp, you're overspeeding the turbine way beyond its original specified rpm range. MED17 ECU's have a surprisingly complicated physics model to control the chargers.

Intake air mass is a very good indication of the produced engine power. It seems you think this the wrong way round. If your AFR is off, your engine wont breath properly and thus gives less air massflow. Same with ignition. On a charged engine, you might end up having alot of boost but not that much airflow. Boost isnt even that important as you should know, mass airflow is what counts, because thats the used amount of air, and more you use air, the more you produce power.

As you know, ignition/AFR control is easy on these cars, power stays almost constant between 11.0-12.5:1, EGT changes by about 50C (still should be less than 950C on WOT run through 4th), ignition has bigger effect on EGT, running less than 14deg at redline starts to increase EGT quickly to over 1000C, and at 6000rpm it wont take 20deg even with 100RON and 11:1 AFR. All these assuming roughly ISA conditions.

About your 1/4 mile comment, you forgot I said trap speed not ET. You can have the same trap speed with 5 car lenghts difference. Try it...

Its sad people think I'm a troll, I can assure you I'm not.

 

[skeat12]

Ah the game is afoot Watson!

Trollage!

Think i'll go with the anonymous theory now

Just to clarify, I mean the compressor wheel of the turbocharger. That is the wheel that compresses intake air, and gets its power from the turbine wheel that is rotated by exhaust gasses.
You can think of it as a wing on airflow, where it creates high pressure and low pressure areas. It also has an angle of attack to the intake airflow, and when the angle of attack increases too much, the compressor stalls.
Very basic thing about aerodynamics and wings is that a wing always stalls at the same angle of attack. The angle of attack is dependant of the intake air mass/speed and compressors rotational speed. Thats why turbocharger manufacturers produce compressor maps.

Thats also why there's a limit of how much air a compressor wheel can produce, because eventually it will stall. You can have a very powerful N/A engine where the turbocharger does only harm, because the compressor is fully stalled just by the amount of air inhaled by the engine (well, that would mean you'd have a 12-litre marine diesel and a K03 but just to give you an idea what I mean).

I do not have to "estimate" the rpm, its actually mapped in the ECU by OEM engineers. There is a map in the ECU where its told how fast the turbocharger rotates at certain airflow and engine rpm. To achieve enough airflow to reach 230hp, you're overspeeding the turbine way beyond its original specified rpm range. MED17 ECU's have a surprisingly complicated physics model to control the chargers.

Intake air mass is a very good indication of the produced engine power. It seems you think this the wrong way round. If your AFR is off, your engine wont breath properly and thus gives less air massflow. Same with ignition. On a charged engine, you might end up having alot of boost but not that much airflow. Boost isnt even that important as you should know, mass airflow is what counts, because thats the used amount of air, and more you use air, the more you produce power.

As you know, ignition/AFR control is easy on these cars, power stays almost constant between 11.0-12.5:1, EGT changes by about 50C (still should be less than 950C on WOT run through 4th), ignition has bigger effect on EGT, running less than 14deg at redline starts to increase EGT quickly to over 1000C, and at 6000rpm it wont take 20deg even with 100RON and 11:1 AFR. All these assuming roughly ISA conditions.

About your 1/4 mile comment, you forgot I said trap speed not ET. You can have the same trap speed with 5 car lenghts difference. Try it...

Its sad people think I'm a troll, I can assure you I'm not.

My head hurts

 

[dera]

Actually, lets just do some maths.

Lets assume, and I'll round values up a bit just to keep things simple...

Engine capacity is 1400cc.
HP target is 230hp
Max rpm shall be lets say 6500
ISA conditions, intake air temps very low 25C at full sing.
AFR 11.5:1

Lets even make this more easy, lets assume engine VE is 95%, and BSFC is very low 0.55.

Now we calculate airflow to reach 230hp. Formula for that is Wa = Hp*AFR*BSFC/60

Wa = 230 * 11.5 * 0,55/60 = 24,24 lb/min of air. 183 grams per second, so we are a bit optimistic here. Anyway...

Then we calculate the MAP required for that:

map = (Wa * R * (460+Tiat)) / (VE * rpm/2 * Engine capacity in cubic inches, 85,43CI)

R = gas constant, 639,6, Tiat is intake air temp (in F), rpm is rpm, VE = our 95% Volumetric Efficiency.

So we have:

MAP = (24,24 * 639,6 * (460+77)) / (0,95 * 6500/2 * 85,43) = 31,56psi - atmospheric 14,7psi at sea level = 16,9psi = 1,16bar of boost at 6500rpm.

We'll assume VERY low pressure losses to the IC etc, normally standard systems at these airflow levels are 4-5psi, lets say 1psi here, so we need 17,9psi of boost now. Thats 1,23bar.

Now we just have to calculate the pressure ratio, which is output psi/intake psi, 31,56/14,7 = pressure ratio of 2,14. Didnt calculate any intake losses, usually they are about to 1psi with a good cold air intake kit.

So, plotting this pressure ratio and airflow on the compressor map (which unfortunately usually arent public...), but try it on an old K03 compressor map, and you'll see we are so beyond its capabilities its almost insane.

This is how these things actually are calculated, unfortunately I dont have the exact VE and BSFC for this engine, but based on that air mass, we're not too far off.

 

[vRSy]

Are you uk base, obviously your a tuner or a very good blagger lol so who are you working for and what's your opinion on the capabilities of the 1.4tsi with full stage 2+remap/IC/intake, decat tbe

 

[dera]

very good blagger

No need to blag, that was just a rough calculation of how unrealistic 230hp is from the standard turbo. There are alot of other variables as well to take into account, but its in the ballpark.

 

[VRSLOZ]

My head hurts

I'm with you

 

[jc_boc]

No need to blag, that was just a rough calculation of how unrealistic 230hp is from the standard turbo. There are alot of other variables as well to take into account, but its in the ballpark.

Still have not answered Sy's question mate. Are you a serious tuner and where are you based and what do you do for a living? Personally, you sound like a lecturer to me hehehehehehehhehe

 

[dera]

Still have not answered Sy's question mate. Are you a serious tuner and where are you based and what do you do for a living? Personally, you sound like a lecturer to me hehehehehehehhehe

I've been working full-time with OEM ECU's for just under 10 years now.
Not based in the UK.

Sorry for sounding like a lecturer. I'll just stick to yes and no from now on.

 

[GrDuDe_Cupra]

Actually, lets just do some maths.

Lets assume, and I'll round values up a bit just to keep things simple...

Engine capacity is 1400cc.
HP target is 230hp
Max rpm shall be lets say 6500
ISA conditions, intake air temps very low 25C at full sing.
AFR 11.5:1

Lets even make this more easy, lets assume engine VE is 95%, and BSFC is very low 0.55.

Now we calculate airflow to reach 230hp. Formula for that is Wa = Hp*AFR*BSFC/60

Wa = 230 * 11.5 * 0,55/60 = 24,24 lb/min of air. 183 grams per second, so we are a bit optimistic here. Anyway...

Then we calculate the MAP required for that:

map = (Wa * R * (460+Tiat)) / (VE * rpm/2 * Engine capacity in cubic inches, 85,43CI)

R = gas constant, 639,6, Tiat is intake air temp (in F), rpm is rpm, VE = our 95% Volumetric Efficiency.

So we have:

MAP = (24,24 * 639,6 * (460+77)) / (0,95 * 6500/2 * 85,43) = 31,56psi - atmospheric 14,7psi at sea level = 16,9psi = 1,16bar of boost at 6500rpm.

We'll assume VERY low pressure losses to the IC etc, normally standard systems at these airflow levels are 4-5psi, lets say 1psi here, so we need 17,9psi of boost now. Thats 1,23bar.

Now we just have to calculate the pressure ratio, which is output psi/intake psi, 31,56/14,7 = pressure ratio of 2,14. Didnt calculate any intake losses, usually they are about to 1psi with a good cold air intake kit.

So, plotting this pressure ratio and airflow on the compressor map (which unfortunately usually arent public...), but try it on an old K03 compressor map, and you'll see we are so beyond its capabilities its almost insane.

This is how these things actually are calculated, unfortunately I dont have the exact VE and BSFC for this engine, but based on that air mass, we're not too far off.

I am very happy the conversation is going this way, I have to admit that this is going beyond my knowledge and i dont want to look like an idiot pretending i know everything, i will discuss this with my mechanic today and i ll get back to you. Thanx for bothering writing all of the above!

 

[dera]

So just to simplify my earlier response:

Even with VERY optimal conditions (hardly any pressure losses, very low BSFC, very high VE and 25C IAT after IC) you STILL need that much airflow to reach that kind of power, which just isnt realistic.

Sy's and jcboc's figures seem realistic, but there isn't much left on that turbo before you're so much beyond its choke line its almost scary.
Based on my limited experience from Dyno Dynamics (only done maybe 50 runs on those), I would say Sy and jcboc both have about 180hp on the wheels, which DD turns into 210ish hp and Maha into 232hp...

 

[dera]

I am very happy the conversation is going this way, I have to admit that this is going beyond my knowledge and i dont want to look like an idiot pretending i know everything, i will discuss this with my mechanic today and i ll get back to you. Thanx for bothering writing all of the above!

In my opinion, the most important feature of a dyno (Maha LPS-series is a very good dyno) is repetability. That way you can see the effect of even the slightest changes. Dyno is a tool for engine tuning after all. Like Revo Kev said earlier, its all dyno lottery anyway. Sy's and jcboc's dyno results are comparable with themselves, but not with the Maha result. Comparing absolute figures from one dyno to another, especially with a "conventional" dyno like Maha to a Dyno Dynamics, which doesnt use DIN70020 correction, is a bit pointless.

Most conventional dynos overread.

The reason for this is when you strap the car down, you always increase resistance, which means the drivetrain losses measured at coastdown show too high readings, which makes the wheel->crank horsepower calculation incorrect.

To give an example of what this means, imagine pushing a car when there's 2 guys trying to push it down from the front at the same time. It requires more force than without those 2 guys.

Also the car hardly ever is 100% straight on the rollers, this force, again, causes excess drag which makes the coastdown measurement, again, incorrect.

For OEM purposes, they use laser alignment to have the car completely straight, and have special bars to keep the car lined up and "strapped down" without any downward force.

The comment I made about pushing the brake on coastdown is an old dyno operator joke, didnt mean you faked the graph by purpose!

Thats why, for me, your 180ish wheel hp is very close to the 210ish DD horsepower Sy and jcboc were seeing, and my original point was just to explain there isnt 20hp left to be had with just tweaking the software.

 

[jc_boc]

I never meant you sounded like a lecturer in a negative way mate, so please don't misunderstand my statement. It was merely meant in the way you describe everything with all the figures etc, would be like a lecturer did in a lecture hall (not that I have ever been to a lecture). So what about this other machine they use to check power where the wheel is taken off the car. Have no idea what it's called but some one was talking about it at the beginning of the thread I think.

 

[dera]

I never meant you sounded like a lecturer in a negative way mate, so please don't misunderstand my statement. It was merely meant in the way you describe everything with all the figures etc, would be like a lecturer did in a lecture hall (not that I have ever been to a lecture). So what about this other machine they use to check power where the wheel is taken off the car. Have no idea what it's called but some one was talking about it at the beginning of the thread I think.

No prob

The machine you describe is a so-called hub dyno, I think Rototest is the most common one in Europe, used that manymany times. It connects directly to the wheel hub eliminating the strapdown/car or wheel aligment inaccuracies. It does very accurate one-point measurements, but is not that good on producing power graphs, because it has no inertia. Modern ECU's dont like them much.

They are very nice when tuning a car, but I dont think their power graphs are that accurate over the whole RPM range. For example, boost spikes usually dont show on those dynos.

 

[jc_boc]

interesting, thanks for clearing that up for me mate.

 

[vRSy]

So in summary as the thread title said, this is exactly what stage 2 1.4tsi's truthfully make.

 

[Deleted member 49882]

Been an interesting read this whole thread ... amazing the level of knowledge and hands on experience some guys have. Wish I knew half of what some of these guys do ... oh, and had the money to do half the work on my car that they do lol

 

[Nutkin]

the pipe that goes around the engine looks very restrictive i wonder what the upgrade potential is here :/