RS7 APR stage 2, Peak Horsepower too low on DYNO, Anyone experience this? Suggestions

[RS7Boss]

Hello Members,

I recently got APR Downpipes and an APR stage 2 tune put in my car. 2017 Rs7 Prestige with 25k miles on it. No other modifications, car had never been tuned before. Car felt immediately faster from the start. Dragy Numbers went from 11.55 down to 11.14 on the 1/4 miles. When I dyno'd my car the power was way short. See Dyno Below. On the Mustang Dynometer, Peak Torque went from 457 to 652 Lb ft. of torque. But the Peak HP only went from 502 AWHP to 542 AWHP. Has anyone experienced this? And if so what are some suggestions to get my horsepower up.

I contacted APR and sent them my Logs they requested and they are looking at them to see what might be the issue. They had said everything looked good but that the intake air temp was high at 70 celcius or about 158 degrees farenheit. Said that I might need to upgrade my heat exchanger. They asked me to take my car back to to the DYNO for the 3rd time and log while on the dyno and resend them the results. I will most likely spend more money to do this, but even if they find out whats wrong, they really won't be doing anything.

I am well within my right to return the tune, and am thinking about doing that if we don't get this sorted out. What would you guys do? any better tuning/ custom tuning solutions? Would getting a different tune solve this issue?

Thanks in advance, Dyno Below,
- Spencer

IMG_3773.jpg

[IowaRS7]

The APR tune is strong but pretty aggressive. If I take temps were that high you likely had timing pull and reduced boost which would result in less peak HP. Mustang dynos also readmlow to begin with. Dynos in high ambient heat and poor air flow are known for seeing high intake temps as well. Better test is to log out in the open road with adequate airflow to see if intake temps are still an issue or if timing is still getting pulled at all.


Sent from my iPhone using Audizine

[kebabman]

Return the APR tune and buy a DS1 from www.dynospectrum.com. The OTS tunes are very solid, and you can log at ridiculous speeds if you need to get the car dialed in further, all the stages are free and open so you can view and edit them yourself. Oh and it’s $1299 so you can keep the $2000 price difference for something else.

[Chris Morales]

Why is anyone still buying APR tunes for this platform? Make them give you your money back and buy the DS1.

[NardoRS7]

It’s 2020 and people are still using dynos to measure gains

[Chris Morales]

Well in fairness he did a dragy run too and only saw an 11.1. It would be more telling to know the trap speed. Some freak stock RS7s have done 11.2 in ideal conditions.


Sent from my iPhone using Audizine

[RS7Boss]

Well in fairness he did a dragy run to and only saw an 11.1. It would be more telling to know the trap speed. Some freak stock RS7s have done 11.2 in ideal conditions.


Sent from my iPhone using Audizine

Hi Chris,

Thank you for your input. My before tune and downpipes run best was 11.52s @ 119.02 MPH while the after Tune and DP time best was 11.11 @124.05 mph. The increase does seem more significant than a 40 whp increase would suggest right?

[Chris Morales]

Definitely more than 40 hp, but don’t worry about the dyno. Even if you’re on 91 octane, it should be a bit quicker. Are you at elevation? Are you sure you’re engaging AMAX?


Sent from my iPhone using Audizine

[Hofahome]

11.1 for a stage 2 RS7 seems slow and corroborates your low hp on the dyno. My bet is that IATs are affecting your power but you need to log


Sent from my iPhone using Tapatalk

[NardoRS7]

Hi Chris,

Thank you for your input. My before tune and downpipes run best was 11.52s @ 119.02 MPH while the after Tune and DP time best was 11.11 @124.05 mph. The increase does seem more significant than a 40 whp increase would suggest right?

My car went 11.2 @ 122mph stock and 10.9 at 128mph on apr stage 2, so the gains are similar.

[Hofahome]

I thought Stg 2 RS7s typically run mid to low 10’s?


Sent from my iPhone using Tapatalk

[IowaRS7]

Really depends on altitude though too, need more info. I still wouldn’t worry about the dyno. It doesn’t represent really road conditions. Poor airflow could easily hinder the dyno results.


Sent from my iPhone using Audizine

[NardoRS7]

I thought Stg 2 RS7s typically run mid to low 10’s?


Sent from my iPhone using Tapatalk

On race gas they run low to mid 10s. On pump gas (93 octane in my runs), mid to high 10s

[Hofahome]

On race gas they run low to mid 10s. On pump gas (93 octane in my runs), mid to high 10s

Ahhh. Thanks!


Sent from my iPhone using Tapatalk

[Wkraus]

Return the canned tune, buy the ds1, then add a custom tune and go e85. You’ll be set for anything you want to do! With the money you wasted on the marketing companies tune your can buy the tune, the tcu tune, a custom tune, and the parts to go e85 I’m thinking. And have the car perform or act any way you want it to I had them lengthen my pops to 1.5 seconds, and have the boost come in hard at low rpm as I like the sledgehammer feel! Please dump apr. Nobody is wasting that kind of money anymore with such a better option now. I was an apr guy for many cars. Never again.

[RS7Boss]

Return the canned tune, buy the ds1, then add a custom tune and go e85. You’ll be set for anything you want to do! With the money you wasted on the marketing companies tune your can buy the tune, the tcu tune, a custom tune, and the parts to go e85 I’m thinking. And have the car perform or act any way you want it to I had them lengthen my pops to 1.5 seconds, and have the boost come in hard at low rpm as I like the sledgehammer feel! Please dump apr. Nobody is wasting that kind of money anymore with such a better option now. I was an apr guy for many cars. Never again.

Thanks for the input guys! I am going to dump the APR and go DS1 looks like and just use the stage 1 tune until I can get a custom tune. That seems to be the way to go. What are the power gains for E85 on the DS1 over 91 pump gas?

I currently have APR down pipes. Is it highly recommended that I get the SRM Long Intake to go with the APR downpipes for a stage 2 custom Tune? Who is the best Tuner to get a custom Tune? I live in San Jose California, and wouldn't it be best to get a custom Tuner to tune me directly on a Dyno , as opposed to someone in Europe where I just send my logs in?

Thanks for the advice

[kebabman]

Thanks for the input guys! I am going to dump the APR and go DS1 looks like and just use the stage 1 tune until I can get a custom tune. That seems to be the way to go. What are the power gains for E85 on the DS1 over 91 pump gas?

I currently have APR down pipes. Is it highly recommended that I get the SRM Long Intake to go with the APR downpipes for a stage 2 custom Tune? Who is the best Tuner to get a custom Tune? I live in San Jose California, and wouldn't it be best to get a custom Tuner to tune me directly on a Dyno , as opposed to someone in Europe where I just send my logs in?

Thanks for the advice

You will likely be able to run stage 2 with just the downpipes and RS inlets, but you’ll need to log to be sure. Ethanol adds a lot of power over 91, can be 100hp depending on the tune and adequate fuel system performance. Not sure exactly what the gains are on OTS but it’s a blend map from E10-50 so it’ll be a sliding scale, above E50 it just runs the ethanol maps. On an RS7 generally without any upgrades to the LPFP you won’t get much above E45-50. Again it’s a case of increasing incrementally and logging though until you see the fuel pressures start to crash under load.

Custom tuning on a dyno is the fastest way for sure, you can get someone familiar with DS1 (SRT, Vency @ Madness Motorsport, Roman Katsev, Boosted Euro) to live tune remotely working in tandem with a local tuner - one of the really nice things about DS1 is it allows calibration changes while the vehicle is running without re-flashing - but road tuning by sending logs and getting revised files also works pretty well, it’s just a lot slower process.

[VinnysS4]

You will likely be able to run stage 2 with just the downpipes and RS inlets, but you’ll need to log to be sure. Ethanol adds a lot of power over 91, can be 100hp depending on the tune and adequate fuel system performance. Not sure exactly what the gains are on OTS but it’s a blend map from E10-50 so it’ll be a sliding scale, above E50 it just runs the ethanol maps. On an RS7 generally without any upgrades to the LPFP you won’t get much above E45-50. Again it’s a case of increasing incrementally and logging though until you see the fuel pressures start to crash under load.

Custom tuning on a dyno is the fastest way for sure, you can get someone familiar with DS1 (SRT, Vency @ Madness Motorsport, Roman Katsev, Boosted Euro) to live tune remotely working in tandem with a local tuner - one of the really nice things about DS1 is it allows calibration changes while the vehicle is running without re-flashing - but road tuning by sending logs and getting revised files also works pretty well, it’s just a lot slower process.

Love this info!


Sent from my iPhone using Tapatalk

[RS7Boss]

You will likely be able to run stage 2 with just the downpipes and RS inlets, but you’ll need to log to be sure. Ethanol adds a lot of power over 91, can be 100hp depending on the tune and adequate fuel system performance. Not sure exactly what the gains are on OTS but it’s a blend map from E10-50 so it’ll be a sliding scale, above E50 it just runs the ethanol maps. On an RS7 generally without any upgrades to the LPFP you won’t get much above E45-50. Again it’s a case of increasing incrementally and logging though until you see the fuel pressures start to crash under load.

Custom tuning on a dyno is the fastest way for sure, you can get someone familiar with DS1 (SRT, Vency @ Madness Motorsport, Roman Katsev, Boosted Euro) to live tune remotely working in tandem with a local tuner - one of the really nice things about DS1 is it allows calibration changes while the vehicle is running without re-flashing - but road tuning by sending logs and getting revised files also works pretty well, it’s just a lot slower process.

Thanks for the info! I returned the tune and ordered a DS1 and RSM intake. So I will be running the OTS Stage 2 for now, then will try to Tune my car with one of the recommended DS1 dealers.

My IAT temps seem to be the reason why my car is heat soaking and losing power. Can anyone recommend some cooling options for my car? I only plan to go stage 2 for now.

[John@DEADBEEF_DynoSp]

Have a chat with SRM re cooling. Water methanol injection is also amazing on this platform. Proper dyno cooling fans also help. An enclosed cell with fans that draw from outside and cover large parts of the front of the car with huge volumes of air then good extraction allows more representative dyno testing. Log charge temp on the road and see how it compares. If you do not run all the boost your charge temps will also be better.