[Dark_Knight_335]

If you're not running higher boost levels than normal or a tune there's really no point. N55 stockers come with a sufficient OC.

[Andrewe92]

I'm not really adding much here, but like other people have pointed out the n55 and n54 does run really hot in terms of oil temp when compared to other cars in the same class or power range. Having said that, the most popular aftermarket cooler that I'll seen is ER . If you're willing to set aside some time and money go for it and share results ! It's the only way you'll know how great or not so great of a mod it is!

[SUPAN]

I have gone the stett way and you find a big difference!

[M-terkait]

Originally Posted by Andrewe92

I'm not really adding much here, but like other people have pointed out the n55 and n54 does run really hot in terms of oil temp when compared to other cars in the same class or power range. Having said that, the most popular aftermarket cooler that I'll seen is ER . If you're willing to set aside some time and money go for it and share results ! It's the only way you'll know how great or not so great of a mod it is!

I will go try ER after they release it next weeks for F30's.

[Zebaztian7]

Any updates?

[Ozzie335i]

There are a few oil thermostats on the market. Worth considering. Can drop the oil temps down by 20 degrees. I went with the AD, as it allows the engine to warm up quicker in the winter.

[Zebaztian7]

Originally Posted by Ozzie335i

There are a few oil thermostats on the market. Worth considering. Can drop the oil temps down by 20 degrees. I went with the AD, as it allows the engine to warm up quicker in the winter.

The problem with me is that my car does not come with the oil cooler

[CantCatchMe]

Originally Posted by Zebaztian7

The problem with me is that my car does not come with the oil cooler

A custom tune helps in a way by increasing the duty cycle. My temps now without an oil cooler don't go past 220(on warm days), ever. During the winter my temps were around 200-210. I do plan to get a used oil cooler from this shop 15 mins away from me. They have plenty of oil coolers on E9X's in their lot. ER is definitely an option I may aquire if the prices are similar.

[STR8-6IX]

To everyone concerned about oil temps there are a step of things you can do to bring temps down before deciding whether you need an oil cooler or not. For starters, removing the plastic engine cover and insulation underneath helps. I would stick to a good oil like motul, liquimoly shell rotella 5w40 as this will help stabilize temps. If you are tracking or simply concerned about underhood temps I would go for a cowl delete (made by BMS I believe) this is a must for track use. Also oil shears and becomes less effective at maintaining temp after 5000 miles so I would change at around then. All this should help keep oil temps reasonable.

[bbnks2]

A few things being posted here that are a bit of a myth that won't help anyone if you are referring to oil temps on a track...

The cowl is a necessary part of your engine bay. Removing it does NOTHING for underhood temps at speed on a track. Air does not get removed from the cowl area at speed. If you delete your cowl on track, air will actually be forced from the windshield to down under the car causing excessive lift. All that additional air pressure in the engine bay will do is make your radiator less effective as less air will want to force its way through at the front of the car. Air at the front of the car will simply go over or under the car. The only possible way the cowl delete will benefit you is at idle in the pits where heat could potentially use that area to escape the engine bay...

Thicker oil = more heat. Period. In fact, if you move from something like T6 to any LL-01 approved oil you will probably run COOLER as T6 is a thicker oil than what BMW specs for our engines. It doesn't matter what oil you put in the car, you are going to have to change it more frequently if you track the car. Lets be honest, 80 minutes of track time isn't going to magically destroy your oil at even the advanced driver level. I do more damage to my oil by sitting in stop and go traffic traffic for 2 hours a day to get to work.

I can't comment on the engine cover. I really don't see it as making any meaningful change to temps, but hey why not take it off for track days. It can't hurt.

The best bang for you buck thing you can do is ditch the coolant as soon as temps get above freezing! Run water + water wetter. You will see a dramatic drop in coolant temps and therefore oil temps. Plain and simple, water is more effective than coolant at transferring heat.

Run a front splitter. A front splitter will force more air through the radiator. The effects will probably be negligible, but there is a reason why track cars run splitters. There are benefits to both Cooling and aerodynamics.

Get a custom tune that runs the water pump a bit harder. The stock cooling tables are written for what conditions BMW expected the car to see on the street. You need to bump up the water pumps duty cycle to remove the excessive heat built up in the head from high load and high rpm driving especially if you're tuned for more power.

Next step after that is getting more aggressive and upgrading the stock 10row tube and fin oil cooler to something with better cooling capacity. Look into a 19-26 row bar and plate oil cooler. It really isn't that hard to do and you don't need to spend $1500.

Oil thermostats aren't going to do anything on track. They will only help for daily driving if you don't like to sit at BMW's target range of 230-250f. The stock thermostat is fully open at 250f. You will still hit 250f within 1 lap on track whether you run the stock thermostat that fully opens at 250f or a lower temp thermostat that fully opens at 210f... At the end of the day, the stock cooling systems will still be the limiting factors!

Stick to at least a 230f oil thermostat if you daily drive your car. Anything lower is asking for moisture buildup in the oil. Honestly, people get all scared about BMW's hitting 270-280f oil on track. Big deal. The American muscle cars see 300+ oil and 240+ coolant on the regular. Ask the next corvette you see on track what their temps are. BMW set the threshold at over 300f before the engine reduces power and synthetic oil holds its viscosity well up to about that point. Just make sure you oil pressure is staying on target! Obviously keeping oil under 250 is better for power production and cylinder head temperatures though and is much more ideal...

[bbnks2]

If all you want to do is pulls on the street then you're approach is going to be different. Doesn't seem like it's worth ANY effort to get street oil temps down to lower than 250f. You'll actually make more power with the 250f oil than 200f oil.

What you'll want to do is focus on keeping your COOLANT temps in check. Again, water pump tuning, an upgraded radiator, and straight water will keep coolant temps down. That in turn will keep the cylinder head running cooler allowing for better power production. Oil temps will drop a bit as a by-product of that. BMW calls for 190f coolant in max performance mode, but the stock cooling system doesn't seem to be able to achieve that on the street let alone on a track.

[STR8-6IX]

Originally Posted by bbnks2

A few things being posted here that are a bit of a myth that won't help anyone if you are referring to oil temps on a track...

The cowl is a necessary part of your engine bay. Removing it does NOTHING for underhood temps at speed on a track. Air does not get removed from the cowl area at speed. If you delete your cowl on track, air will actually be forced from the windshield to down under the car causing excessive lift. All that additional air pressure in the engine bay will do is make your radiator less effective as less air will want to force its way through at the front of the car. Air at the front of the car will simply go over or under the car. The only possible way the cowl delete will benefit you is at idle in the pits where heat could potentially use that area to escape the engine bay...

Thicker oil = more heat. Period. In fact, if you move from something like T6 to any LL-01 approved oil you will probably run COOLER as T6 is a thicker oil than what BMW specs for our engines. It doesn't matter what oil you put in the car, you are going to have to change it more frequently if you track the car. Lets be honest, 80 minutes of track time isn't going to magically destroy your oil at even the advanced driver level. I do more damage to my oil by sitting in stop and go traffic traffic for 2 hours a day to get to work.

I can't comment on the engine cover. I really don't see it as making any meaningful change to temps, but hey why not take it off for track days. It can't hurt.

The best bang for you buck thing you can do is ditch the coolant as soon as temps get above freezing! Run water + water wetter. You will see a dramatic drop in coolant temps and therefore oil temps. Plain and simple, water is more effective than coolant at transferring heat.

Run a front splitter. A front splitter will force more air through the radiator. The effects will probably be negligible, but there is a reason why track cars run splitters. There are benefits to both Cooling and aerodynamics.

Get a custom tune that runs the water pump a bit harder. The stock cooling tables are written for what conditions BMW expected the car to see on the street. You need to bump up the water pumps duty cycle to remove the excessive heat built up in the head from high load and high rpm driving especially if you're tuned for more power.

Next step after that is getting more aggressive and upgrading the stock 10row tube and fin oil cooler to something with better cooling capacity. Look into a 19-26 row bar and plate oil cooler. It really isn't that hard to do and you don't need to spend $1500.

Oil thermostats aren't going to do anything on track. They will only help for daily driving if you don't like to sit at BMW's target range of 230-250f. The stock thermostat is fully open at 250f. You will still hit 250f within 1 lap on track whether you run the stock thermostat that fully opens at 250f or a lower temp thermostat that fully opens at 210f... At the end of the day, the stock cooling systems will still be the limiting factors!

Stick to at least a 230f oil thermostat if you daily drive your car. Anything lower is asking for moisture buildup in the oil. Honestly, people get all scared about BMW's hitting 270-280f oil on track. Big deal. The American muscle cars see 300+ oil and 240+ coolant on the regular. Ask the next corvette you see on track what their temps are. BMW set the threshold at over 300f before the engine reduces power and synthetic oil holds its viscosity well up to about that point. Just make sure you oil pressure is staying on target! Obviously keeping oil under 250 is better for power production and cylinder head temperatures though and is much more ideal...

before all the 0w nonsense, BMW recommended 5w30/5w40 for the n52, n54, n55 for a long time. I have tried all the oil weights and oil temp was most stable and by far the lowest when using 5w40 rotella. just speaking from personal experience.

I have removed the plastic engine cover myself in basically any warm weather conditions, and it makes an almost 50F difference in oil temps which is major. even for the street this is not a bad idea to do because our cars run so hot just sitting in traffic on a warm day. as for the cowl delete.. good information. it does make sense what you said, but wouldnt the cowl delete help air be forced through the engine bay and out the cowl? I havent see what the cowl delete physically looks like, so I wont comment on that.. How about installing a vented hood perhaps? or even making a custom little vent in your engine bay to simply expel heat.

honestly for the track, or any sort of half spirited driving I would be using nothing but 5w40. It does protect the engine more and temps were improved for me when switching to 5w40. my 2011 manual made NO mention of a 0w, only the new manuals did and I am not having any of it. we switched to 5w30 oil from 0w20 in my dads mazda and the car loved it, ran 10x smoother and quieter. will never use 0w again in my life.

Originally Posted by bbnks2

If all you want to do is pulls on the street then you're approach is going to be different. Doesn't seem like it's worth ANY effort to get street oil temps down to lower than 250f. You'll actually make more power with the 250f oil than 200f oil.

What you'll want to do is focus on keeping your COOLANT temps in check. Again, water pump tuning, an upgraded radiator, and straight water will keep coolant temps down. That in turn will keep the cylinder head running cooler allowing for better power production. Oil temps will drop a bit as a by-product of that. BMW calls for 190f coolant in max performance mode, but the stock cooling system doesn't seem to be able to achieve that on the street let alone on a track.

190F... coolant temps wont go anywhere near that even during normal driving lol. honestly, some of the things I mentioned like thicker oil and removing the engine cover makes sense literally for simple street driving.. 250F oil temp is HOT. that is an abnormal oil temperature for sitting in traffic, and the average car will only see temperatures like this subjected to track abuse on a hot summer day. I think it is important to do whatever you can to keep oil temps lower then this even if you do not track the vehicle. it does help the engine operate more efficiently due to less friction, but your engine is operating more efficiently at the expense of your engine gaskets over the long run and probably the overall health of the motor. you will never achieve an optimal 190F coolant temp if oil is at 250f..

anyways, I know many people on the track crank the heater up. this actually reduces coolant temps by quite alot. I would suggest this to keep coolant temps down as well. (depending on the situation)

but for starters, in basically any ambient weather 37F or above, remove your engine cover. also run 5w40 those two things alone will stabilize temps considerably.

[Welcome to NBA Jam]

240-250F is definitely normal operating temperature on the N55. You can expect it to hover close to that value, on average; this is also why it's in the center of the gauge. The thermostat fully opens around 230F.

From the manual: 210-300F is a completely normal temperature range.

A larger oil cooler will allow your car to stay within that range under track conditions when the car is working hardest. Increasing the efficiency of your cooling system is equally, if not more, important. Mishimoto and CSF both make great drop-in all aluminum radiators. I personally prefer the CSF one over Mishimoto.

[bbnks2]

Originally Posted by STR8-6IX

before all the 0w nonsense, BMW recommended 5w30/5w40 for the n52, n54, n55 for a long time. I have tried all the oil weights and oil temp was most stable and by far the lowest when using 5w40 rotella. just speaking from personal experience.

0w/5w is the COLD viscosity of the oil. Thinner oil on startup = better cold start protection. That has nothing to do with the viscosity of the oil when it gets up to operating temperature (30/40w).

I've seen other people say they have 10-15f higher oil temps with Rotella so we really need some data. Rotella is factually a thicker oil than anything LL-01 approved though. Can't speak for how it behaves in our cars since I haven't used it. I've hear good things though.

Originally Posted by STR8-6IX

I have removed the plastic engine cover myself in basically any warm weather conditions, and it makes an almost 50F difference in oil temps which is major. even for the street this is not a bad idea to do because our cars run so hot just sitting in traffic on a warm day.

I'll definitely give it a try too.

Originally Posted by STR8-6IX

As for the cowl delete.. good information. it does make sense what you said, but wouldn't the cowl delete help air be forced through the engine bay and out the cowl? I haven't see what the cowl delete physically looks like, so I wont comment on that.. How about installing a vented hood perhaps? or even making a custom little vent in your engine bay to simply expel heat.

Hood vents would be ideal right behind the radiator in the area of low pressure. The air flowing over the hood would literally suck the hot air that just came through the radiator out of the engine bay. Air only flows through the radiator because it wants to move from the high pressure region at the front of the car to the area of low pressure under the hood. By removing the cowl, the engine bay will no longer be an area of low pressure. Less air will want to force it's way into the engine bay through the radiator at the front of the car. The difference is hard to measure, but the science supports cowl deletes are bad.

Originally Posted by STR8-6IX

honestly for the track, or any sort of half spirited driving I would be using nothing but 5w40. It does protect the engine more and temps were improved for me when switching to 5w40. my 2011 manual made NO mention of a 0w, only the new manuals did and I am not having any of it. we switched to 5w30 oil from 0w20 in my dads mazda and the car loved it, ran 10x smoother and quieter. will never use 0w again in my life.

See first comment above.

Also, the car be quieter due to thicker oil (moving from 20w to 30w) is a bit of a myth too. Just because the valvtrain makes more noise at idle with 20w oil doesn't mean its wearing any differently than 30w.

Originally Posted by STR8-6IX

190F... coolant temps wont go anywhere near that even during normal driving lol. honestly, some of the things I mentioned like thicker oil and removing the engine cover makes sense literally for simple street driving.. 250F oil temp is HOT. that is an abnormal oil temperature for sitting in traffic, and the average car will only see temperatures like this subjected to track abuse on a hot summer day. I think it is important to do whatever you can to keep oil temps lower then this even if you do not track the vehicle. it does help the engine operate more efficiently due to less friction, but your engine is operating more efficiently at the expense of your engine gaskets over the long run and probably the overall health of the motor. you will never achieve an optimal 190F coolant temp if oil is at 250f.

The car runs in different "modes" based on driving conditions. Cruising on the highway, or sitting in traffic, the water pump only spins enough to keep coolant at 236f for EFFICIENCY. When you get on the gas you'll notice coolant temps instantly start to DROP to lower targets. "open map" cooling tables target 190f for maximum power output. Since just about everyone on the forum has a tune, I don't thin any of us can achieve that 190f goal anymore. Water pump output needs to be altered to account for the extra heat.

I can assure you that water temps can drop to 190f during a 3rd gear pull even when oil is at 250f. Water wetter alone makes this much more possible without any water pump table changes. 2-3 4th gear pulls later and things still change for the worse though... cooling system can't keep up with the heat and you won't be able to get down to that 190f water temp anymore on consecutive pulls.

[STR8-6IX]

Originally Posted by bbnks2

0w/5w is the COLD viscosity of the oil. Thinner oil on startup = better cold start protection. That has nothing to do with the viscosity of the oil when it gets up to operating temperature (30/40w).

I've seen other people say they have 10-15f higher oil temps with Rotella so we really need some data. Rotella is factually a thicker oil than anything LL-01 approved though. Can't speak for how it behaves in our cars since I haven't used it. I've hear good things though.



I'll definitely give it a try too.



Hood vents would be ideal right behind the radiator in the area of low pressure. The air flowing over the hood would literally suck the hot air that just came through the radiator out of the engine bay. Air only flows through the radiator because it wants to move from the high pressure region at the front of the car to the area of low pressure under the hood. By removing the cowl, the engine bay will no longer be an area of low pressure. Less air will want to force it's way into the engine bay through the radiator at the front of the car. The difference is hard to measure, but the science supports cowl deletes are bad.



See first comment above.

Also, the car be quieter due to thicker oil (moving from 20w to 30w) is a bit of a myth too. Just because the valvtrain makes more noise at idle with 20w oil doesn't mean its wearing any differently than 30w.



The car runs in different "modes" based on driving conditions. Cruising on the highway, or sitting in traffic, the water pump only spins enough to keep coolant at 236f for EFFICIENCY. When you get on the gas you'll notice coolant temps instantly start to DROP to lower targets. "open map" cooling tables target 190f for maximum power output. Since just about everyone on the forum has a tune, I don't thin any of us can achieve that 190f goal anymore. Water pump output needs to be altered to account for the extra heat.

I can assure you that water temps can drop to 190f during a 3rd gear pull even when oil is at 250f. Water wetter alone makes this much more possible without any water pump table changes. 2-3 4th gear pulls and things change for the worse...

generally whenever I get onto the throttle the oil temp will always rise a little bit but will go back to normal within 5 minutes if it is cool outside. in warm weather, it just seems to always want to creep towards 250f and will stay there regardless of what I do. even with 5w40 oil... even with the engine cover removed. used to be so much worse.

regarding 5w40 oil, I am simply speaking from personal experience. I have tried different oil weights, had the best experience with 5w40, the manual states that using this weight is fine so this is what I will continue to use.

as for the hood vents, so you can cut open a little 3 sided square and push the vent outwards so heat comes out of the engine bay. so you want to do this right behind the radiator, essentially at the front of the engine bay right? do you think this would help underhood temps and somehow change overall oil temps?

also, I would code the water pump to just overall work harder if I could. I always see my temps creep toward 240-250f even when it is not very hot outside.

[bbnks2]

Originally Posted by STR8-6IX

The manual states that using this weight is fine so this is what I will continue to use.

I thought we covered this in another thread, lol. The manual states you can use LL-01 approved 5w-40. It DOES NOT say you can use any 5w-40 you find on the shelf. SAE 40 is just a range between a cSt of 12.5 and 16.3.

http://www.tribology-abc.com/abc/viscosity.htm

Rotella has a higher cSt and cP (viscosity) than any LL-01 data sheet I've seen. Again, not saying it's bad or anything just trying to share the information I've researched.

Originally Posted by STR8-6IX

as for the hood vents, so you can cut open a little 3 sided square and push the vent outwards so heat comes out of the engine bay. so you want to do this right behind the radiator, essentially at the front of the engine bay right? do you think this would help underhood temps and somehow change overall oil temps?

Here is the thread you'll want to read: http://www.e90post.com/forums/showthread.php?t=1306425

Originally Posted by STR8-6IX

also, I would code the water pump to just overall work harder if I could. I always see my temps creep toward 240-250f even when it is not very hot outside.

That must be your oil temps. My oil temps sit at 240-250 even in the dead of winter. It's normal for my driving style. I don't like to shift a lot with the manual. Water temps should never be that high. not even on track have I seen more than 23xf.

Personally, I'd only adjust the water pump tables for that high output "characteristic map" that the car runs. I'd personally want to retain the efficiency benefits of running the water hotter while in traffic. That's just me though. I don't know if N55 tuning even has that ability yet though. Seems like Wedge is the only one altering water pump tables and his changes seems to be across the board in ALL driving conditions. I really don't want my water pump running 100% 24/7. It's pointless and less efficient...

[STR8-6IX]

Originally Posted by bbnks2

I thought we covered this in another thread, lol. The manual states you can use LL-01 approved 5w-40. It DOES NOT say you can use any 5w-40 you find on the shelf. SAE 40 is just a range between a cSt of 12.5 and 16.3.

http://www.tribology-abc.com/abc/viscosity.htm

Rotella has a higher cSt and cP (viscosity) than any LL-01 data sheet I've seen. Again, not saying it's bad or anything just trying to share the information I've researched.



Here is the thread you'll want to read: http://www.e90post.com/forums/showthread.php?t=1306425



That must be your oil temps. My oil temps sit at 240-250 even in the dead of winter. It's normal for my driving style. I don't like to shift a lot with the manual. Water temps should never be that high. not even on track have I seen more than 23xf.

Personally, I'd only adjust the water pump tables for that high output "characteristic map" that the car runs. I'd personally want to retain the efficiency benefits of running the water hotter while in traffic. That's just me though. I don't know if N55 tuning even has that ability yet though. Seems like Wedge is the only one altering water pump tables and his changes seems to be across the board in ALL driving conditions. I really don't want my water pump running 100% 24/7. It's pointless and less efficient...

right, I did not clarify myself. I meant 240f oil temps in slightly warm weather on the highway in top gear when the water pump gets lazy and tries to raise temps for efficiency. in cooler weather I am literally always sitting at the first quarter mark, or roughly 205-210f oil temp because I keep my engine cover removed.

this is probably the first and last time I will use shell rotella. I saw nothing wrong with it, its actually a great oil regardless of the fact it does not meet LL spec but I will be using liqui moly 5w40 from now on.

anyways.. you should definitely try removing your plastic engine cover. be sure to remove the insulation shit underneath too which apparently the n55 has. It will help in literally any weather 35F+. I basically only keep it on only in the dead of winter when its really cold.

someone said that these high oil temps accelerate the wear of our engine gaskets, and our gaskets seem to be always failing and it scientifically makes sense. cooler temps = longer gasket life right?

[STR8-6IX]

Originally Posted by bbnks2

I thought we covered this in another thread, lol. The manual states you can use LL-01 approved 5w-40. It DOES NOT say you can use any 5w-40 you find on the shelf. SAE 40 is just a range between a cSt of 12.5 and 16.3.

http://www.tribology-abc.com/abc/viscosity.htm

Rotella has a higher cSt and cP (viscosity) than any LL-01 data sheet I've seen. Again, not saying it's bad or anything just trying to share the information I've researched.



Here is the thread you'll want to read: http://www.e90post.com/forums/showthread.php?t=1306425



That must be your oil temps. My oil temps sit at 240-250 even in the dead of winter. It's normal for my driving style. I don't like to shift a lot with the manual. Water temps should never be that high. not even on track have I seen more than 23xf.

Personally, I'd only adjust the water pump tables for that high output "characteristic map" that the car runs. I'd personally want to retain the efficiency benefits of running the water hotter while in traffic. That's just me though. I don't know if N55 tuning even has that ability yet though. Seems like Wedge is the only one altering water pump tables and his changes seems to be across the board in ALL driving conditions. I really don't want my water pump running 100% 24/7. It's pointless and less efficient...

I just looked over the link you provided here. so low pressure areas are best for expelling hot air from the engine bay, and high pressure areas are best for an intake right? low pressure areas being closer to the front where the rad is, and high pressure being closer to the cowl so it makes no sense to do a cowl delete.

scientifically all of this does make sense. so I suppose a strategically placed hood vent will be more effective then getting rid of hot air through your cowl (which is probably there for air pressure and aerodynamic purposes anyways.)

so what do you think is the purpose of keeping underhood temps cool? I know it wont make much of a difference for intake temperatures because the intake draws in cool air from above the radiator, but it would keep the intake manifold cooler so perhaps a small difference for intake temps? small difference for coolant and oil temps? allow the radiator to operate more efficiently? anything else I am missing?

[bbnks2]

Originally Posted by STR8-6IX

I just looked over the link you provided here. so low pressure areas are best for expelling hot air from the engine bay, and high pressure areas are best for an intake right? low pressure areas being closer to the front where the rad is, and high pressure being closer to the cowl so it makes no sense to do a cowl delete.
The cowl is there to keep the air feeding your climate system from going under the car and creating lift. It also keeps engine bay fumes out of your cabin air system as well.

scientifically all of this does make sense. so I suppose a strategically placed hood vent will be more effective then getting rid of hot air through your cowl (which is probably there for air pressure and aerodynamic purposes anyways.)

That is what I have gathered, yes. Miata forums are a better place for this kind of research. people hack those things up for all sorts of crazy projects.

Originally Posted by STR8-6IX

so what do you think is the purpose of keeping underhood temps cool? I know it wont make much of a difference for intake temperatures because the intake draws in cool air from above the radiator, but it would keep the intake manifold cooler so perhaps a small difference for intake temps? small difference for coolant and oil temps? allow the radiator to operate more efficiently? anything else I am missing?

Well there is a few reasons why hood vents are good. First, The hot air from the radiator wouldn't have to pass under the car creating lift. The hot air could simply flow right back out from under the hood. Second, You really don't want the 200-300f air that just got superheated by the radiator to then pass through the engine bay and under the car. That would heat everything up and keep it toasty under there... Have you ever noticed how hot the transmission tunnel near your legs gets in the summer? I am sure it would be more ideal if these components didn't have to get heated by the hot air from the radiator. Finally, yes the radiator would operate more efficiently as well due to the pressure differential created by the hood vents. More air would flow through the radiator instead of going under/over the car.

Something I noticed on the N55, IAT's shoot up at idle and stay there once you do a few pulls. things get "heatsoaked" way more than N54's. I took an infrared gun and hit a bunch of components under my hood. The intercooler itself was dead on with ambient, so I can't blame the intercooler. The chargepipes were over 300f... Things get hot under the hood and I think we would really benefit from hoods vents. I want to get a carbon fiber hood eventually with some vents. I do think it would help.

[STR8-6IX]

Originally Posted by bbnks2

That is what I have gathered, yes. Miata forums are a better place for this kind of research. people hack those things up for all sorts of crazy projects.




Well there is a few reasons why hood vents are good. First, The hot air from the radiator wouldn't have to pass under the car creating lift. The hot air could simply flow right back out from under the hood. Second, You really don't want the 200-300f air that just got superheated by the radiator to then pass through the engine bay and under the car. That would heat everything up and keep it toasty under there... Have you ever noticed how hot the transmission tunnel near your legs gets in the summer? I am sure it would be more ideal if these components didn't have to get heated by the hot air from the radiator. Finally, yes the radiator would operate more efficiently as well due to the pressure differential created by the hood vents. More air would flow through the radiator instead of going under/over the car.

Something I noticed on the N55, IAT's shoot up at idle and stay there once you do a few pulls. things get "heatsoaked" way more than N54's. I took an infrared gun and hit a bunch of components under my hood. The intercooler itself was dead on with ambient, so I can't blame the intercooler. The chargepipes were over 300f... Things get hot under the hood and I think we would really benefit from hoods vents. I want to get a carbon fiber hood eventually with some vents. I do think it would help.

i completely forgot! I actually have a great example as to why hood vents are great. so I had this shitty manual lancer last year and I got a ram intake for cheap that I slapped on. It didnt make much of a difference in performance until I unbolted the hood and wedged the cowl end of the hood open about 1CM. but then again... that is a high pressure area like we discussed, so I am not sure it made such a big difference. but I remember touching the metal part of the intake before and after wedging the hood open and the metal on the intake was cool to the touch afterwards.. so it did make a difference.

anyways, a vented hood is just plain awesome from an aesthetics point to begin with, not to mention extremely useful for cooling purposes regardless of whether it is a street car or for the track. a main reason why I try to keep my oil temps low is because I heard oil deteriorates very quickly and must be changed within 3000miles if temps hit 230-250f, and that the oil is immediately useless once it hits 260f and must be replaced. I am simply quoting this from a nissan forum or something, not sure if this is true or not but it very well may indicate the oil doesnt like these high temps and will shear quicker then it otherwise would.

for the time being, I am happy enough with oil temps just from using 5w40 and removing the engine cover. I also crank the heater up when driving aggressively as this lowers coolant temps considerably. like someone else mentioned, lower coolant temps allow the cylinder head to operate more effectively. in the meantime, I guess this is the most I can do until getting a vented hood which I feel like will be really good in terms of keeping things cool under the hood.

I suppose you can open the hood periodically when stopped or taking a break to remove heatsoak, but that is not exactly convenient to do given most circumstances and everything will probably be heatsoaked again within a couple minutes.

why do you think the n55 heatsoaks more then the n54? sounds like a radiator issue perhaps since you are stopped? most likely I think the chargepipe or downpipe is too close to the engine bay and ruining temps. would wrapping these in some sort of heat reflective material make a difference?

would underhood temperatures be affected by the fact that I dont use my engine cover? because on one hand it should mainly only trap heat within the engine block, but then again removing it lowers oil temps which should therefore help with underhood temps, right?

sorry, lots of questions here. but this is an interesting topic for sure.

[STR8-6IX]

Originally Posted by bbnks2

That is what I have gathered, yes. Miata forums are a better place for this kind of research. people hack those things up for all sorts of crazy projects.




Well there is a few reasons why hood vents are good. First, The hot air from the radiator wouldn't have to pass under the car creating lift. The hot air could simply flow right back out from under the hood. Second, You really don't want the 200-300f air that just got superheated by the radiator to then pass through the engine bay and under the car. That would heat everything up and keep it toasty under there... Have you ever noticed how hot the transmission tunnel near your legs gets in the summer? I am sure it would be more ideal if these components didn't have to get heated by the hot air from the radiator. Finally, yes the radiator would operate more efficiently as well due to the pressure differential created by the hood vents. More air would flow through the radiator instead of going under/over the car.

Something I noticed on the N55, IAT's shoot up at idle and stay there once you do a few pulls. things get "heatsoaked" way more than N54's. I took an infrared gun and hit a bunch of components under my hood. The intercooler itself was dead on with ambient, so I can't blame the intercooler. The chargepipes were over 300f... Things get hot under the hood and I think we would really benefit from hoods vents. I want to get a carbon fiber hood eventually with some vents. I do think it would help.

another thing worth mentioning.. the OP of this thread mentioned he thinks the engine runs best with oil temps at 200-210F, and I can 100% vouch for this. these are the temps I see with the engine cover removed in cool ambient conditions, and the oil sort of seems like the perfect thickness for the engine. just seems to be the optimal oil temp compared to 240-250f.

also, 210f oil temps means the coolant temps will be closer to the optimal figure of 190f which is why I want to code my water pump to work harder. all this with a hood vent should help keep everything perfect under the hood.

[juld0zer]

Wrapping the chargepipe and the TMAP sensor with a layer of exhaust wrap and a layer of foil sarking loosely wrapped over it makes a noticeable difference in IAT. Driveability i cant say is impacted that much by high IAT to be honest but there is definitely a lot of heatsoak going on when the car is stationary.

Oil temps - either change the thermostat or take the thermostat out but oil temps might be too cool. In that case you might be able to reduce the cooling ability by adding a flyscreen or something to impede airflow