[miksebik]

Hi,
we have F30 335i with PS2 and supporting mods. Fuel is straight petrol. The intercooler is Wagner competition stg.2. We dynoed around 490HP so far, but the high temps are limiting advance in high rpms.

For some weird reason we are seeing unusually high IATs:

outside: 70F
cruising, normal driving, speed up to 100kmh: 104-110F
WOT on 5th (street): 90F at start, going to 126F.
WOT on 5th (dyno): 92F going to 135(140)F

My E92 335i is going around 8C degrees above ambient when cruising..

The intake tube itself is very hot (sure, it is in engine bay), but still.. this cannot be normal. Whats going on?

[ZM2]

It’s the IC. The Wagner Comp 2 can’t keep up with a tuned N55 under load.

I’m only ~425whp and would see IATs hit 160F on hot summer track days, and could see temps 50F above ambient after several back to back street 3-4-5 pulls.

So, I retrofitted the Evo3 Comp to my M2: https://f87.bimmerpost.com/forums/sh....php?t=1727351

[AmuroRay]

IC is too small, you’ll want to upgrade to the VRSF Race or Wagner Evo 3.

[miksebik]

OK, that sounds good. My tuner (Motiv) recommended this VRSF. Also we have an option to get a do88 intercooler, but it shows only 5C better temps after a pull than Wagner stg2.
From what I read/you say.. it looks like the VRSF RACE.
Thanks guys.

[AmuroRay]

Originally Posted by miksebik

OK, that sounds good. My tuner (Motiv) recommended this VRSF. Also we have an option to get a do88 intercooler, but it shows only 5C better temps after a pull than Wagner stg2.
From what I read/you say.. it looks like the VRSF RACE.
Thanks guys.

Great choice, and yeah the Do88 would still be too small. Do some before and after logs when you get it

[Munchi435i]

I've been running my wagner Evo comp 2 for a few years and don't have those kinds of high IAT's. But I'm also running ethanol mix so that might also play a part in cooling lol.

I'll be dyno tuning my car next Saturday and we shall see how my wagner holds up. Maybe I need to upgrade to wagner comp 3???!

[thejeremyman9]

Originally Posted by Munchi435i

I've been running my wagner Evo comp 2 for a few years and don't have those kinds of high IAT's. But I'm also running ethanol mix so that might also play a part in cooling lol.

I'll be dyno tuning my car next Saturday and we shall see how my wagner holds up. Maybe I need to upgrade to wagner comp 3???!

The ethanol has no impact on IATs. The N55 is a DI engine.

But yeah the IAT rise on the dyno will be interesting.

[ZM2]

Originally Posted by thejeremyman9

The ethanol has no impact on IATs. The N55 is a DI engine.

But yeah the IAT rise on the dyno will be interesting.

True, but it keeps power up and pulls less timing with high IATs.

Since we all have air to air intercooling it’s pretty much a given that there’s no way to keep IATs below 100-105F on a hot summer track day, and timing will be pulled on pump gas even with the best IC on the market. That’s my main reason for doing a half 93/E85 tune, so I don’t have to pay $10/gal for race gas and there’s little power loss when IATs go over 100F.

So far, IATs drop to 10-12F above ambient on the first pull with my Evo3, and maxes out at around 25F above ambient—but, that’s with a ridiculous amount of back to back 3-4-5 pulls and hard braking in between. Results on track should be similar—we’ll see!

[Munchi435i]

Originally Posted by ZM2

True, but it keeps power up and pulls less timing with high IATs.

Since we all have air to air intercooling it’s pretty much a given that there’s no way to keep IATs below 100-105F on a hot summer track day, and timing will be pulled on pump gas even with the best IC on the market. That’s my main reason for doing a half 93/E85 tune, so I don’t have to pay $10/gal for race gas and there’s little power loss when IATs go over 100F.

So far, IATs drop to 10-12F above ambient on the first pull with my Evo3, and maxes out at around 25F above ambient—but, that’s with a ridiculous amount of back to back 3-4-5 pulls and hard braking in between. Results on track should be similar—we’ll see!

My E40 fuel should cool the engine better compared to straight 93 octane. But I'm sure while dynoing my IAT's will rise significantly! I do not track my car and feel the wagner comp 2 will be sufficient even living in hot humid Florida weather. If it becomes an issue ill just add some meth for some additional cooling only.

[thejeremyman9]

Originally Posted by ZM2

True, but it keeps power up and pulls less timing with high IATs.

Since we all have air to air intercooling it’s pretty much a given that there’s no way to keep IATs below 100-105F on a hot summer track day, and timing will be pulled on pump gas even with the best IC on the market. That’s my main reason for doing a half 93/E85 tune, so I don’t have to pay $10/gal for race gas and there’s little power loss when IATs go over 100F.

So far, IATs drop to 10-12F above ambient on the first pull with my Evo3, and maxes out at around 25F above ambient—but, that’s with a ridiculous amount of back to back 3-4-5 pulls and hard braking in between. Results on track should be similar—we’ll see!

Yes i know, but the discussion here was specifically for IATs. I am an advocate for ethanol (and mixes) and run the E20 MHD map myself. I also run 50/50 91/E85 in my 3000gt and may eventually go full 85 once i have the fuel system to support it. In any case, ill never go back to pump gas, especially given how bad our 91 is in California and how many timing issues it causes. I even somewhat quantified that in my virtual dyno thread (substantial power loss from timing with same hardware, same tune, etc).

Originally Posted by Munchi435i

My E40 fuel should cool the engine better compared to straight 93 octane. But I'm sure while dynoing my IAT's will rise significantly! I do not track my car and feel the wagner comp 2 will be sufficient even living in hot humid Florida weather. If it becomes an issue ill just add some meth for some additional cooling only.

I mean... I guess you can say it burns cooler, but again i was just saying its not affecting IATs in any way.

[ZM2]

Originally Posted by Munchi435i

My E40 fuel should cool the engine better compared to straight 93 octane. But I'm sure while dynoing my IAT's will rise significantly! I do not track my car and feel the wagner comp 2 will be sufficient even living in hot humid Florida weather. If it becomes an issue ill just add some meth for some additional cooling only.

It does help with engine cooling some, but won’t be noticeable for your use case and only an E40 mix. Race cars that run full E85 see noticeable improvement.

The Evo2 is also fine for your use case. It’s just when you start pushing big HP or are tracking the N55 that you need one of the mega IC’s.

[ZM2]

Originally Posted by thejeremyman9

Yes i know, but the discussion here was specifically for IATs. I am an advocate for ethanol (and mixes) and run the E20 MHD map myself. I also run 50/50 91/E85 in my 3000gt and may eventually go full 85 once i have the fuel system to support it. In any case, ill never go back to pump gas, especially given how bad our 91 is in California and how many timing issues it causes. I even somewhat quantified that in my virtual dyno thread (substantial power loss from timing with same hardware, same tune, etc).



I mean... I guess you can say it burns cooler, but again i was just saying its not affecting IATs in any way.

I knew you knew, just helping to enlighten other folks.

[AmuroRay]

More boost and timing means it will run hotter. Get a proper IC, and or consider meth.

PS2 + Small IC = even on the street.

[lens]

Originally Posted by miksebik

Hi,
we have F30 335i with PS2 and supporting mods. Fuel is straight petrol. The intercooler is Wagner competition stg.2. We dynoed around 490HP so far, but the high temps are limiting advance in high rpms.

For some weird reason we are seeing unusually high IATs:

outside: 70F
cruising, normal driving, speed up to 100kmh: 104-110F
WOT on 5th (street): 90F at start, going to 126F.
WOT on 5th (dyno): 92F going to 135(140)F

My E92 335i is going around 8C degrees above ambient when cruising..

The intake tube itself is very hot (sure, it is in engine bay), but still.. this cannot be normal. Whats going on?

It depends on how much boost vs timing your tuner is doing as well, but it seems your FMIC can't keep up. I run the ATM FMIC and it keeps up really well with PS2.

Things to keep in mind, more boost less timing=more heat more inconsistent power, more timing, less boost=less heat, a bit less but more consistent power.

[thejeremyman9]

Originally Posted by chaungo

It depends on how much boost vs timing your tuner is doing as well, but it seems your FMIC can't keep up. I run the ATM FMIC and it keeps up really well with PS2.

Things to keep in mind, more boost less timing=more heat more inconsistent power, more timing, less boost=less heat, a bit less but more consistent power.

Yeah would like to see OP's logs from the data he reported to see how the tune looks with respect to timing and boost.

[miksebik]

I might post logs later, from what I remember we are around 22PSI and 5 degrees of timing. It is MOTIV, who tunes the car..
We are before 500PS barrier because of the timing and high IAT, when the combustion is not very stable in high revs. My N54 is dialed to 7.8 degrees of timing (19-20PSI). So I am sure that if this was solved, we would see more paths to take (less boost, higher timing, more boost and more timing for max power etc.)

E85 is becoming more and more scarce fuel here

Do you know if the biggest VRSF N55 IC is the same as the biggest one for N54? :-)

Do you think we should do something with the intake too? It is really weird the temps are so high when only "cruising"/driving in a city.

[thejeremyman9]

Originally Posted by miksebik

I might post logs later, from what I remember we are around 22PSI and 5 degrees of timing. It is MOTIV, who tunes the car..
We are before 500PS barrier because of the timing and high IAT, when the combustion is not very stable in high revs. My N54 is dialed to 7.8 degrees of timing (19-20PSI). So I am sure that if this was solved, we would see more paths to take (less boost, higher timing, more boost and more timing for max power etc.)

E85 is becoming more and more scarce fuel here

Do you know if the biggest VRSF N55 IC is the same as the biggest one for N54? :-)

Do you think we should do something with the intake too? It is really weird the temps are so high when only "cruising"/driving in a city.

If E85 isnt an option, you can consider an additive like boostane, if that is available. It's not a long term solution for a daily driven car IMO, although some people do run it that often.

Not sure about the N54 question, but the biggest VRSF IC should be more than enough for a PS2.

Not sure what intake you are running, but a closed intake getting air from the front of the car is the ideal situation for the lowest possible starting IATs. Some will argue that the intake is a moot point with a IC but i tend to disagree with that to an extent. Having said that a completely stock intake might choke a PS2 a little (without at least MPPK bottom and a drop-in filter).

Getting IAT rise with city driving is expected and more or less unavoidable. Everything underhood, CP and intake manifold included, is getting heat soaked. Without actual intake airflow over the sensor you can sit and watch IATs rise sitting at a stoplight for example. As soon as you accelerate away they should drop back down as the intake air flows over the sensor. This usually isnt a concern when doing WOT pulls because the air flow/velocity is high enough the IATs are going to be dominated by IC performance (and the actual air temp) and not how hot your CP may have gotten. Having said that i did recently heat wrap my CP and i noticed an improvement in IATs (lower and closer to ambient) when just doing city driving. It probably had little to no effect on IATs during WOT for the reason i mentioned.