[Kelvin1000]

This is true as long as oil and coolant temperatures don't go above a certain level... After that, you start to lose 1 PSI of boost for every 10 - 15 degrees.

[Slidewayz]

It sure seems like the right kind of hood vents would help since you're always moving on the track.

[AMASIAN]

Hood vents will have a negligible effect.

Turbo blankets
Coated headers
wrapped or coated test pipes

motul mocool or water wetter

any aftermarket thermostats for n54?



Wrapping the turbos and test pipes in my Z made a HUGE difference.

[marcel b]

Originally Posted by zsapphire7

Maybe we need more air volume to pass in front of the car to acheive this. Im thinking about deleting the fogs and using that extra space on both sides for cooling.

This is what I will do next. I started a thread to get the partnumbers. What I see they 335Is bumber intake fits the normal Mtech bumber.
Doubling the oilcooler size (I have the VK oilcooler with Setrab core) only helps to a certain extend when the airflow is not increased. A lot of air will increase its performance.
I have the power kit, the vk oilcooler and the ETS FMIC and I still have too high temps on the track. And I do not have even any engine tune! The DCT is partly to blame for this as well IMO, as this generates a lot of heat as well.

1st I will try the additional air flow with the 335Is intakes which should dramatically increase the flow to the oilcooler and to the 2nd watercooler (power kit) installed at the driver side.
2nd I will try the different coolant.
3th is to install a performance radiator.

Only when I have the temps under control I start thinking in increasing power.

[Praemienhai]

Originally Posted by marcel b

Doubling the oilcooler size (I have the VK oilcooler with Setrab core) only helps to a certain extend when the airflow is not increased. A lot of air will increase its performance.

I think thats the way to go instead of adding another OC (which will block a part of the radiator like the AR design OC). My mechanic which has 20 years experience in the German DTM and other racing series as a mechanic told me the same: try to increase the airflow to the coolers if the upgraded OC isn't working sufficient at the track.

The other point he mentioned is a upgraded radiator due to the fact that the turbos are both water and oil cooled so that the upgrade of the OC only is not the optimal solution even so the water temps will not reach the limit for a limp mode.

[Kelvin1000]

I have to say that as much as I love this car, it is not intended for track use. By the time we spend the $ with all the cooling and performance upgrades, we could have just bought an M3 and been done with it.

[marcel b]

Originally Posted by Kelvin1000

I have to say that as much as I love this car, it is not intended for track use. By the time we spend the $ with all the cooling and performance upgrades, we could have just bought an M3 and been done with it.

would not say it like that, 335 is still cheaper, also to run. For a dedicated trackcar you are right, but when doing 15k miles a year daily driving and 10 trackdays...

[zsapphire7]

Originally Posted by marcel b

would not say it like that, 335 is still cheaper, also to run. For a dedicated trackcar you are right, but when doing 15k miles a year daily driving and 10 trackdays...

yea... we do have much better fuel economy and insurance costs.

[Ironring Racing]

Originally Posted by zsapphire7

Even though it looks like its hard to cool our cars down because of these small turbos making that much heat at 15~psi up in the 5Kto 7K RPM range (~400whp), I think its possible to cool these guys down enough for consistant track power for ~20mins. It just might take a lot more cooling than doubling oil cooling capacity. In fact since theyre both water and oil cooled it may take a combination of both to acheive that but its possible . Berk's 135 seems to have been able to acheive ~ 380whp @ 250-260 oil temps and 240F coolant temps on the track.

Maybe we need more air volume to pass in front of the car to acheive this. Im thinking about deleting the fogs and using that extra space on both sides for cooling.

Not sure how he's doing that, my car runs 240 just cruising on the highway at 65mph. But of course you can keep throwing bigger or additional OC's and rads at it, drop boost. When I drop to 12psi it stayed at about 280, at some lower boost it would run a little cooler. But like I said, my car runs 240 normal, not sure how he's running 250 on the track.

Originally Posted by stressdoc

Two other areas that can help are (1) weight reduction, and (2) aero mods. After installing M Aero front my car stays a bit cooler longer.

Yes, certainly weight. Driver in we're 3800lbs. I'm sure the baby seat in the back of my car doesn't help the temps either! lol At the end of the day it's my daily driver, winter, tows my kart trailer, etc. I'm happy to run within 10 sec of the cup cars, and then drive my daughter to daycare while towing a trailer, all in the same car.

Originally Posted by Kelvin1000

Two comments:

1) I don't know for sure but I would be willing to bet that a stock 335i would drop the boost lower than 8 PSI after a few laps in this heat.

2) I wonder if keepting the EGTs lower with a richer fuel mix might also help. I noticed that the Dinan and GIAC tunes run much different A/F ratios than the Piggybacks...

We need Mr. 5 to chime in since he is always at the track...

No, the OEM "maps" target consistent HP, so actually increase boost as it heats up, until it hits temp high level (280 if I remember correctly) and then cuts back boost before limp mode at 300.

Originally Posted by zsapphire7

As far as i know, the stock settings will actually increase boost with increases in IAT to compensate for the less dense air. This way the car will produce roughly the same amount of power as it does in the cold. However, im sure at some certain oil/coolant temp, the stock ecu will probably drop it down again. My bet is thats what limp mode is...

See above.

Originally Posted by Slidewayz

It sure seems like the right kind of hood vents would help since you're always moving on the track.

Again, tried. Vorsteiner didn't really make a difference at all.

Originally Posted by Praemienhai

I think thats the way to go instead of adding another OC (which will block a part of the radiator like the AR design OC). My mechanic which has 20 years experience in the German DTM and other racing series as a mechanic told me the same: try to increase the airflow to the coolers if the upgraded OC isn't working sufficient at the track.

The other point he mentioned is a upgraded radiator due to the fact that the turbos are both water and oil cooled so that the upgrade of the OC only is not the optimal solution even so the water temps will not reach the limit for a limp mode.

Yes, doesn't take a rocket scientist to say more cooling will keep it cooler. But with the underpanels on the car, limited front air intakes, and a packed engine bay, there's not a lot of air throughput. And yes, obviously the OEM performance rad & fan upgrades would be great if they were bolt-ons, but as I mentioned, limited returns anyway as water temps are fine.

Originally Posted by marcel b

would not say it like that, 335 is still cheaper, also to run. For a dedicated trackcar you are right, but when doing 15k miles a year daily driving and 10 trackdays...

Honestly it's not even about which is cheaper, as a 335 with all these bolt-ons is close enough to call it a wash. But as a daily driver, IMHO the 335 is a much better street car with the boatloads of torque on hand. And is a great track car, with this one weak point.

It's been beaten to death on the forums, but no denying the 335 is lighter, better balance (weight distribution), more torque and thus quicker down low. In my book a better street car. On the track the M3 is great right out of the box, handles great (with camber plates) and will run laps all day without breaking a sweat.

BMW really did hit each target well. I needed to tow the kart, so bought a 335, now have to live with this one issue, but overall I'm very happy with the car, and for me, my needs, my life, it's still the better fit than an M3.

[Kelvin1000]

Is the 335is bumper and cooling ducts a direct fit on the 335i???

[marcel b]

Originally Posted by Kelvin1000

Is the 335is bumper and cooling ducts a direct fit on the 335i???

tryng to find that out. For sure you need to have Mtech, the holes look identical to the ones in the Mtech.
I was just informed that in Europe the dealers cannot (will not) provide these parts
Would be good if somebody in the states tries this

[marcel b]

Originally Posted by Kelvin1000

Is the 335is bumper and cooling ducts a direct fit on the 335i???

trying to find that out. For sure you need to have Mtech, the holes look identical to the ones in the Mtech.
I was just informed that in Europe the dealers cannot (will not) provide these parts
Would be good if somebody in the states tries this

To me the bumper looks like a standard Mtech bumper but without foglights. Would not know why this would not fit.

[Praemienhai]

Originally Posted by Ironring Racing

And yes, obviously the OEM performance rad & fan upgrades would be great if they were bolt-ons, but as I mentioned, limited returns anyway as water temps are fine.

You don't get my point. 115 Deg Celsius water temps are not "fine" although you don't get a limp mode. The target of the ECU with respect to the water temps is 90-95 degree Celsius under continuous full load!

[marcel b]

UPDATE: although in Germany a BMW dealer said they could not deliver these parts, here in Switzerland it is no problem. They where a bit surprised as the parts where not listed in their catalog and that the parts had to come from Münich, but it was no problem to order. Will arrive in a week or so

[zsapphire7]

Originally Posted by Praemienhai

You don't get my point. 115 Deg Celsius water temps are not "fine" although you don't get a limp mode. The target of the ECU with respect to the water temps is 90-95 degree Celsius under continuous full load!

Yea... it looks like we should wait for data from people using radiators to come out.

Theoretically, since water has a specific heat of 2x that of oil, given the same surface area and temperature differential(between the oil/water and the air), the amount of heat removed is twice that of an oil cooler. Since our turbos are probably whats causing most of the heat and are cooled by both water and oil, it means that cooling down just one of them will definately have an effect on the other. We just need to remove as much heat as possible from the system via water or oil.

[Praemienhai]

Originally Posted by zsapphire7

Yea... it looks like we should wait for data from people using radiators to come out.

Theoretically, since water has a specific heat of 2x that of oil, given the same surface area and temperature differential(between the oil/water and the air), the amount of heat removed is twice that of an oil cooler. Since our turbos are probably whats causing most of the heat and are cooled by both water and oil, it means that cooling down just one of them will definately have an effect on the other. We just need to remove as much heat as possible from the system via water or oil.

+1

[The HACK]

Originally Posted by Gobynetwork

FWIW, I took a look at this 135i at the BMW CCA 40th anniversary party for the Los Angeles chapter. I recall this car's mods being just a Dinan oil cooler and Dinan ECU flash. The was running a stock Radiator. I have seen this car run at BMW Club race (~30 minutes) and it does not appear to suffer from any cooling problems. I might add that driver / car combo is very fast. Ralph Warren, driver, has set a few track (HS CLASS) records in this car.

http://www.bimmerfest.com/forums/sho...d.php?t=281136

It does. In fact, most of the time Ralph just goes balls out for a few laps, sets the track record, get in front of people and takes it easy for the rest of the "race" to make sure the car doesn't go limp and become a moving chicane for the rest of the racers.

As far as I know they've never fully solved the heat related limp issues on that car, but Ralph is so freakin' fast and it's pretty much the only car competing in HS that they don't need to push the entire race.

[Doug007]

Originally Posted by zsapphire7

Theoretically, since water has a specific heat of 2x that of oil, given the same surface area and temperature differential(between the oil/water and the air), the amount of heat removed is twice that of an oil cooler.

Not true.

From heat exchanger theory, Heat flux (W, BTU/min) = U * A * dT(LM)

U is the overall heat transfer coefficient for the heat exchanger determined by heat exchanger metal properties, fluid properties, velocities, etc., A is heat transfer area, and dT is the temperature difference (log mean)

http://en.wikipedia.org/wiki/Log_mea...ure_difference

Specific heat only enters into the overall heat transfer coefficient. Water is a much better heat carrier due to its high specific heat. This means for a given heat duty, water will have a lower change in temperature than oil. This is good for heat exchange because the temperature difference is what drives the flow of heat.

I agree, water is the better heat exchange medium. However, the effect is not nearly 2x.

If you're trying to cool the oil the most direct method is an oil/air heat exchanger. Cooling the water/glycol will indirectly cool the oil by cooling the engine block but if oil temps are your problem cool the oil first.

[zsapphire7]

Originally Posted by Doug007

Not true.

From heat exchanger theory, Heat flux (W, BTU/min) = U * A * dT(LM)

U is the overall heat transfer coefficient for the heat exchanger determined by heat exchanger metal properties, fluid properties, velocities, etc., A is heat transfer area, and dT is the temperature difference (log mean)

http://en.wikipedia.org/wiki/Log_mea...ure_difference

Specific heat only enters into the overall heat transfer coefficient. Water is a much better heat carrier due to its high specific heat. This means for a given heat duty, water will have a lower change in temperature than oil. This is good for heat exchange because the temperature difference is what drives the flow of heat.

I agree, water is the better heat exchange medium. However, the effect is not nearly 2x.

If you're trying to cool the oil the most direct method is an oil/air heat exchanger. Cooling the water/glycol will indirectly cool the oil by cooling the engine block but if oil temps are your problem cool the oil first.

sorry correct i think i mixed up the Qs half way. Q dot is whats important . Does anyone know exactly how the turbos are cooled by water and oil? Like does it use a ton of water or just a little bit and rely mostly on oil to cool the turbos?

[Ironring Racing]

Originally Posted by Praemienhai

You don't get my point. 115 Deg Celsius water temps are not "fine" although you don't get a limp mode. The target of the ECU with respect to the water temps is 90-95 degree Celsius under continuous full load!

No, I got your point.

ECU high points for temp are 148C for oil and 117C for water. Above those respective temps, air conditioner and engine power are progressively reduced. Below those temps the engine is at full power. So although we both agree that 115 is high, the ECU considers 115 fine.

In fact, at 90C on the highway the ECU considers the temp too cold, combustion too ineffecient, and reduces the electric water pump cycle in order to raise the temp.

Both of my 335i's (both 2007 E90's, one 6AT, one 6MT) ran at or just over 100C as normal around town operating temp (when they were both stock). Any hard driving at all and they were easily up in the 105-110 range.

These engines simply run hot. If you recall, they actually had to change the oil temp guage/graduation range on the first model years because they had the "middle" of the guage at a more typical 100 or 110, and people were concerned because they were always showing 10-20C over.

[zsapphire7]

Originally Posted by Ironring Racing

No, I got your point, it's just incorrect.

ECU high points for temp are 148C for oil and 117C for water. Above those respective temps, air conditioner and engine power are progressively reduced. Below those temps the engine is at full power. So although we both agree that 115 is high, the ECU considers 115 fine.

In fact, at 90C on the highway the ECU considers the temp too cold, combustion too ineffecient, and reduces the electric water pump cycle in order to raise the temp.

Both of my 335i's (both 2007 E90's, one 6AT, one 6MT) ran at or just over 100C as normal around town operating temp (when they were both stock). Any hard driving at all and they were easily up in the 105-110 range.

These engines simply run hot. If you recall, they actually had to change the oil temp guage/graduation range on the first model years because they had the "middle" of the guage at a more typical 100 or 110, and people were concerned because they were always showing 10-20C over.

Do you have the source on the 148C oil and 117C water temps? Just wondering cuz i thought that the car reduced power before oil got that hot.

[Ironring Racing]

One place is the BMW Engine Management .pdf at the top of this 335i forum.