[F87source]

Originally Posted by AmuroRay

M135i/M235i
https://www.supersprint.com/ww-en/bm...-hp-2013-.aspx

OEM:
Claimed data:
Horsepower 319,9 Hp @ 5800 rpm
Torque 450 Nm @ 1300-4500 rpm

Actual data:
Horsepower 319,9 Hp @ 6250 rpm
Torque 462,5 Nm @ 3140 rpm

vs

Supersprint:
- Centre Pipe 988613
- Rear exhaust Right O100 + Left O100 988624

Actual data:
Horsepower 330,9 Hp @ 6080 rpm
Torque 469 Nm @ 2770 rpm




Vs


Supersprint:
- Downpipe kit + Metallic catalytic converter (100 CPSI) 988521
- Front pipe 988612
- Centre pipe 988613
- Rear exhaust Right O100 - Left O100 988624

Actual data:
Horsepower 347,9 Hp @ 6010 rpm
Torque 486,2 Nm @ 2980 rpm

They all included the rear exhaust systems as well, none of them were mid pipe or front pipe alone.

[AmuroRay]

Originally Posted by F87source

They all included the rear exhaust systems as well, none of them were mid pipe or front pipe alone.

Super Sprint claims almost 50hp (this is measured at the engine, based on the drivetrain loss recorded at the dyno) for their exhaust system, with only 30hp or so being attributed to the downpipe:



The mufflers does jack all for gains:

[F87source]

Originally Posted by AmuroRay

Super Sprint claims almost 50hp (this is measured at the engine, based on the drivetrain loss recorded at the dyno) for their exhaust system, with only 30hp or so being attributed to the downpipe:



The mufflers does jack all for gains:

Very interesting, what is the diameter of the stock m235i mid pipe?

Claims of crank horse power doesn't mean anything because you can't accurately calculate drivetrain loss. The only important number is the before and after wheel horse power measurement.

[AmuroRay]

Originally Posted by F87source

Very interesting, what is the diameter of the stock m235i mid pipe?

Claims of crank horse power doesn't mean anything because you can't accurately calculate drivetrain loss. The only important number is the before and after wheel horse power measurement.

It is measured at the wheel (Radleistung the blue line, means "wheel output") but they use the rollers to figure out resistance and calculate engine horsepower from it.
If you look at the results I posted previously, they have the claimed power and compare it against their dyno measured power.

SuperSprint diameter is 80mm, AWE is 76mm

[sqwinny]

The bottleneck for thr n55 and most f30 cars lies in the downpipe and resonators. The m235 is a true 3” ID but smooshed for clearance past the downpipe and expands again for the resonator + muffler. I have f30 n55 resonator as I was going to put it into my exhaust setup to get rid of the small drone between 2600-2700 at 75-85 mph or so

[F87source]

Originally Posted by AmuroRay

It is measured at the wheel (Radleistung the blue line, means "wheel output") but they use the rollers to figure out resistance and calculate engine horsepower from it.
If you look at the results I posted previously, they have the claimed power and compare it against their dyno measured power.

Exhaust diameter is 80mm

That doesn't even make sense, how do you calculate drive train loss via resistance from the rollers, that's impossible. You can only estimate drivetrain loss, the only way to truly calculate it is to measure it with an engine dyno and compare the results to a standard roller dyno.

[AmuroRay]

Originally Posted by F87source

That doesn't even make sense, how do you calculate drive train loss via resistance from the rollers, that's impossible. You can only estimate drivetrain loss, the only way to truly calculate it is to measure it with an engine dyno and compare the results to a standard roller dyno.

That's exactly what it's doing - it's calculating the expected drivetrain loss based off inputed factors (green line) - a lot of dynos do this, including MAHA dynos (this one) and DynoDynamics dynos like what Evolve uses.

edit:

https://rennlist.com/forums/gt4-spyd...o-experts.html

[F87source]

Originally Posted by AmuroRay

That's exactly what it's doing - it's calculating the expected drivetrain loss based off inputed factors (green line) - a lot of dynos do this, including MAHA dynos (this one) and DynoDynamics dynos like what Evolve uses.

edit:

https://rennlist.com/forums/gt4-spyd...o-experts.html

And that's going to be an estimated drivetrain loss because it's impossible to determine drivetrain loss when your only measurement is done at the wheels. And therefore the crank horsepower numbers are mostly meaningless.

[AmuroRay]

AGA cable fix in.

[F87source]

Originally Posted by AmuroRay

AGA cable fix in.

Getting close!

Can't wait to see the results!

[AmuroRay]

I picked up my car today - she's all buttoned up and drives wonderfully. I haven't been able to push it yet, as I was carrying a passenger and the roads weren't open enough.

However, I'll say the VRSF Race intercooler is FANTASTIC. IATs can go as low as 5F over ambient, and I've held <10F during some lower gear pulls. During low speed cruising, I saw as high as 15-20F, but I stepped on the pedal and it immediately dropped down to around less 10F or less. It was 89-90F out according to my display, so this IAT control was welcome.

Also - Zero Lag.

As for the tune - I can't really gather anything from it yet. While it was hot and sunny this afternoon, it's already raining out - so data logging will have to wait

[Kiddvegas]

Originally Posted by AmuroRay

I picked up my car today - she's all buttoned up and drives wonderfully. I haven't been able to push it yet, as I was carrying a passenger and the roads weren't open enough.

However, I'll say the VRSF Race intercooler is FANTASTIC. IATs can go as low as 5F over ambient, and I've held <10F during some lower gear pulls. During low speed cruising, I saw as high as 15-20F, but I stepped on the pedal and it immediately dropped down to around less 10F or less. It was 89-90F out according to my display, so this IAT control was welcome.

Also - Zero Lag.

As for the tune - I can't really gather anything from it yet. While it was hot and sunny this afternoon, it's already raining out - so data logging will have to wait

Makes me wonder if my CTS stepped one will be worth it, or sell it and get the bigger core.

[AmuroRay]

Originally Posted by Kiddvegas

Makes me wonder if my CTS stepped one will be worth it, or sell it and get the bigger core.

Depends on your plans - I have high ambient temperatures and plan on doing more track days - so I felt it was worth it. The little CTS will not hold up in those situations.

[F87source]

Originally Posted by AmuroRay

Depends on your plans - I have high ambient temperatures and plan on doing more track days - so I felt it was worth it. The little CTS will not hold up in those situations.

If you want to track then you don't want the largest intercooler, you have to sacrifice iats for coolant temps. Because a large intercooler blocks too much air flow and causes coolant temps to spike, and on these cars coolant temp is a huge issue with how small the radiator is.

So my advice is to run a high enough octane (ethanol mix) that high iats won't be a problem. Then potentially run water injection to help suppress iats.

[AmuroRay]

Originally Posted by F87source

If you want to track then you don't want the largest intercooler, you have to sacrifice iats for coolant temps. Because a large intercooler blocks too much air flow and causes coolant temps to spike, and on these cars coolant temp is a huge issue with how small the radiator is.

So my advice is to run a high enough octane (ethanol mix) that high iats won't be a problem. Then potentially run water injection to help suppress iats.

I don't believe this at all - the only person who recorded an issue was Zm2, and the Evo 3 is 3" taller than the next tallest intercooler. My Race is basically occupying space in front of the crash brace - there is nothing to block.

[ZM2]

Let’s expand on the IC/track topic over here: https://f87.bimmerpost.com/forums/sh....php?t=2024707

I still don’t know the best approach. Another guy I know running a Stg 2 tune, full CSF cooling pack, and the ER IC had coolant temp issues (IATs were fine), as well.

[F87source]

Originally Posted by AmuroRay

I don't believe this at all - the only person who recorded an issue was Zm2, and the Evo 3 is 3" taller than the next tallest intercooler. My Race is basically occupying space in front of the crash brace - there is nothing to block.

You forget that these intercoolers press right up against the radiator (technically the ac condenser) or are right there in that region, when the suction fan pulls for more air the intercooler will be right there blocking clean air flow and transferring extra heat.


But that's the simplistic answer, if you look at it from an air flow perspective the m2 has a fairly good ducting system from the factory. It takes all the air from the lower inlet and expands that outwards to a larger volume while ducting that to the radiator and intercooler. This expansion drops the air speed and increases air pressure which is very vital because higher pressure allows better air flow through radiator cores, and the lower speed allows better thermal exchange. This is the principle behind race car ducting - the expansion.

When you shove a massive intercooler there, that expansion no longer takes place and all the air ducted to the radiator now has to go through an intercooler. So yes it's absolutely blocking air flow to the radiator, because the duct can't channel air there anymore.


This is effectively what the stock m2 duct is doing:

Here's what the duct looks like:
https://www.ecstuning.com/b-genuine-...r/51748062165/


It takes all the air from the center opening and tries to expand that and duct it to both the radiator and the intercooler. It can't do that if a giant intercooler is in the way.

The duct itself is also "ok", it could be so much better if it was a single solid piece of carbon or plastic or metal, with really good flow attachment - like a diffuser.

[AmuroRay]

Originally Posted by ZM2

Let’s expand on the IC/track topic over here: https://f87.bimmerpost.com/forums/sh....php?t=2024707

I still don’t know the best approach. Another guy I know running a Stg 2 tune, full CSF cooling pack, and the ER IC had coolant temp issues (IATs were fine), as well.

Well, I'm a non M - So I'm not going to be apples to apples because I don't have the same ducting.

[AmuroRay]

The issue Zm3 is likely having is the DCT cooler and tall intercooler are blocking airflow to his radiator - there is no cooler there on my car.

[ZM2]

Originally Posted by AmuroRay

The issue Zm3 is likely having is the DCT cooler and tall intercooler are blocking airflow to his radiator - there is no cooler there on my car.

I’m running the stock DCT cooler and instead, a larger DCT pan, but I know 6MT guys with the same issue.

It’s all about the larger aftermarket IC’s blocking air to the radiator on tuned cars. That’s where you run into coolant temp issues on hot track days.

I’m fine with IATs 40F above ambient on hot track days since I’m running E50, but IDK which IC is best to have at least that much control over IAT on a 480whp car while keeping as much airflow to the radiator, or if both are even possible.

Hence my thought for the smallest IC that has decent IAT control and blocks the least amount of airflow, and I can supplement with simple, non-tune dependent water injection if needed.

[AmuroRay]

Originally Posted by ZM2

I’m running the stock DCT cooler and a larger DCT pan, but I know 6MT guys with the same issue.

It’s all about the larger aftermarket IC’s blocking air to the radiator on tuned cars. That’s where you run into coolant temp issues on hot track days.

I’m fine with IATs 40F above ambient on hot track days since I’m running E50, but IDK which IC is best to have at least that much control over IAT on a 480whp car while keeping as much airflow to the radiator, or if both are even possible.

Hence my thought for the smallest IC that has decent IAT control and blocks the least amount of airflow, and I can supplement with simple, non-tune dependent water injection if needed.

I just don't see how that's possible

Look how much space you have available:


Vs


Ooof. Sorry for the low quality picture - I was in the garage with low light.
But according to this video -

All they removed was the front duct that just ducted small intercooler. The top of the intercooler was (and is) still sealed, at least on my car.

[ZM2]

Originally Posted by AmuroRay

I just don't see how that's possible

Look how much space you have available:


Vs


Ooof. Sorry for the low quality picture - I was in the garage with low light.
But according to this video -

All they removed was the front duct that just ducted small intercooler. The top of the intercooler was (and is) still sealed, at least on my car.

Well, it’s very possible bc it’s happening.