N54 Cooling - Temp Control Logic and what are your temps during extended track use?

[Asbjorn]

Damn I guess this is one reason to avoid twin turbo setups. The GC lites have coolant flowing through them, right?

Yes they are oil and coolant cooled. At 18-19psi (20psi peak), I run them way below their max, so I am not sure if they actually develop less heat than the stockers would at 380whp. Maybe @Chris@VargasTurboTech knows.

Anyhow, at this exact circuit, I have witnessed a tuned M135i (pure stage 2, single turbo) hit power reduction on a hotter day, while S55 powered cars (twin turbo) seem to be doing okay. All of us with similar power and lap times.

I think it has actually been confirmed that the water pump will indeed run at full tilt in ALL cooling modes. So no, the car should not see rising coolant temps of 220f+ if it's running in normal mode targeting 205f.

The big difference the MHD cooling changes make is that you can force the car to run in "High+KFT" mode at all times (by lowering the ambient thresholds) which means that it will drop the coolant temp more aggressively in areas of the race track where coolant temps can be kept low. This then gives you more "headroom" again before temps rise again in the faster parts of the track that require a lot of throttle. so instead of entering the straight away with 205f coolant and peaking 230f you might enter the straight away at 180f coolant and peak 210f.

It works a little bit, but cooling capacity is still exceeded and coolant temps still trend upwards after successive laps.

Yes, in my experience, running MHD race mode only delays the problem, it doesn't increase peak capacity. But I will give it a shot with the new cooling setup.

How did you get that second radiator to fit? From the description it sounds like its sitting above the FMIC, thus you didn't push the stock radiator back at all?

Yes, above the FMIC, in front of the condenser, behind the DCT oil cooler. Didn't have to touch the condenser or CSF stock location radiator. Here's an awful picture, but you get the idea:

Z4 has plently of space up front, although I had to remove the intake snorkel.

 

[barry@3DM]

Haven't been able to keep up with what's being discussed here, too much going on! Would be happy to revisit down the road though.

Track season and warm weather is approaching fast! lol

Makes me think of doing a poll to gauge interest on who wants a cooling solution for track use.

@barry@3DM
@Bnks334 ?
@MDORPHN ?
@Asbjorn ?
@Torgus ?
@berns ?

 

[RSL]

You can see in the second log that coolant is at 90C before and after the hot laps. This indicates that dme has entered sport mode, probably due to pushing it during warm up and during the hot lapping.

We are modifying the cooler setup this week and I will try and include testing with and without race mode activated next time. May even turn the heater on lol.

FYI, I set ECO and normal both to 80C and drove around. It DOES pop in to modes 5 then 4 on the way out (high+KFT/high) after a WOT (below the ambient threshold), so there does appear to be a separate full/heavy-throttle component to activating it regardless of thresholds. It's only hits after or well into the full/heavier pedals and then only stays briefly, probably because request doesn't stay high. Ideally, you'd want it in high+KFT full-time on the track, but it obviously can/will get to it, at least periodically.

What I find slightly odd, is that it pulls heating to the thermostat and ramps water pump when goes into high+KFT that way.

datazap.me | RSL | Cooling test - 80C ECO and norm

datazap.me

I think it has actually been confirmed that the water pump will indeed run at full tilt in ALL cooling modes. So no, the car should not see rising coolant temps of 220f+ if it's running in normal mode targeting 205f.

The big difference the MHD cooling changes make is that you can force the car to run in "High+KFT" mode at all times (by lowering the ambient thresholds) which means that it will drop the coolant temp more aggressively in areas of the race track where coolant temps can be kept low. This then gives you more "headroom" again before temps rise again in the faster parts of the track that require a lot of throttle. so instead of entering the straight away with 205f coolant and peaking 230f you might enter the straight away at 180f coolant and peak 210f.

It works a little bit, but cooling capacity is still exceeded and coolant temps still trend upwards after successive laps.

True, but they don't seem to work with the same urgency as high+KFT. It will only stay in high+KFT as base mode so long as you're above the ambient temp threshold, which means the air temps needs to be 80F+ on MHD race cooling and 90F+ for MHD sport for it to be active full-time. It's easy enough to change the settings in the XDF, but would be something people might want/need to adjust on the spot at the track. Flash-time user threshold/target input specifically for high+KFT, rather than defined values, might be nice.

 

[Chris@VargasTurboTech]

Yes they are oil and coolant cooled. At 18-19psi (20psi peak), I run them way below their max, so I am not sure if they actually develop less heat than the stockers would at 380whp. Maybe @Chris@VargasTurboTech knows.

Shaft speed and compressor discharge temps will be less at any given boost pressure vs. stock turbos... less heat.

 

[shushikiary]

Track season and warm weather is approaching fast! lol

Makes me think of doing a poll to gauge interest on who wants a cooling solution for track use.

@barry@3DM
@Bnks334 ?
@MDORPHN ?
@Asbjorn ?
@Torgus ?
@berns ?

I'd be interested in a solution, but the issue is I already have 2 oil coolers and the 900 IC FMIC, one oil cooler in the stock location, the second one goes in front of my radiator above the FMIC.

So the only space I have to add a "second" radiator would be in the driver wheel well, where the IS puts their dinky little one. OR it would have to find another home somehow, like the trunk.

I wonder how much work it would be to put a radiator in the rear where we have extra space due to no spare. The issues would obviously be centered around running long coolant lines to the trunk, the fact that its right above the mufflers, and needing some way to funnel air across the radiator.

I ALSO really wonder how big of a difference it would make if if was easier for the air to escape the cramped engine bay, aka hood vents (as already talked about), or something similar.

 

[barry@3DM]

I'd be interested in a solution, but the issue is I already have 2 oil coolers and the 900 IC FMIC, one oil cooler in the stock location, the second one goes in front of my radiator above the FMIC.

So the only space I have to add a "second" radiator would be in the driver wheel well, where the IS puts their dinky little one. OR it would have to find another home somehow, like the trunk.

I wonder how much work it would be to put a radiator in the rear where we have extra space due to no spare. The issues would obviously be centered around running long coolant lines to the trunk, the fact that its right above the mufflers, and needing some way to funnel air across the radiator.

I ALSO really wonder how big of a difference it would make if if was easier for the air to escape the cramped engine bay, aka hood vents (as already talked about), or something similar.

The radiators (aftermarket included) are tiny in these cars. Its because of the big ass fan and the FMIC. They limit core thickness and frontal surface area respectively.

The fan is so thick you can't put a thicker core radiator in, at least not a PnP one. Next, because of the FMIC being located under the radiator, the radiator is too short which kills frontal surface area.

Unfortunately Increasing frontal area will be difficult as it will likely require a custom FMIC. Increasing core thickness is much more doable. By removing the fan and replacing it with a thinner fan, the core thickness can be increased a lot, possibly up to 2"s thick. The issue to overcome is the backside of the radiator and FMIC are flush and they use one fan for both. This can be overcome by either ducting or using multiple fans, one on the radiator and small ones on the FMIC.

In addition, the DME needs some work. Yes there is MHD "Race" mode but as @RSL has stated, more can be done. Unfortunately this is where my abilities/expertise end.

Ideally, there would be a "Track" setup that would work like this:
-run in warm up mode to let engine warm up
-Once warmed up, run water pump and Thermostat at full tilt, no matter what.
-when car shuts down, run in cool down mode to keep coolant flowing through the turbos to prevent heat soak

If it still runs hot, then start attacking thermostat and waterpump. Another discussion for another day.

 

[shushikiary]

I know SPAL and perma cool make some nice thinner fans and it wouldn't be that bad to make an aluminum shroud for them to fit a much thicker radiator, and the shroud could make up for the loss of IC coverage, or take on extra smaller fans like you said.

The issues I see is either adding an aftermarket fan controller, or figuring out how to translate the stock PWM control to control the fans. I'm willing to bet its a PWM signal at either 5 or 12v, almost all newer cars moved to that over relays to control inrush current (which would nuke the relays), and making sure the fan doesn't blow the stock controller from too much current draw. Then we'd have to deal with maintenance. Currently when you remove the stock fan it gives you a decent amount of room to do things like replace the accessory belt. Thus the fan shroud would need to be easily removable so one could do regular maintenance.

I bet champion or griffin makes a core that is close to the right size already, then a custom mount and a well thought out shroud and mount for said shroud, and finally a proper control system, and it could make a nice kit.

Easily 500 bucks just in metal/parts, I'd be a kit like that would retail for 800 bucks or more.

 

[DaveAU335i]

Sorry for the interruption guys, but I have a massive oil temp issue too. I'm in Australia, don't track the car, though, I do drive it very hard. It's a December built 2007 E93 (auto) 335i. Bought it 2'nd hand from a car-yard. While I'm not mechanically minded (all services/repairs) are done by an Indy Shop.

The car yard I bought it from, as far as I can tell, were clueless to the correct oil to use. And instead, used crap. I wasn't aware of this, until approx 3,000km later, when burnt oil smoke from OFH started to ooze from engine bay. By then, it resembled black-sludge, and had literally clogged the OFH, and stock oil cooler, along with associated piping etc. Took 3x flushes and 2x oil filters, along gasket replacements, and hoses cleaned to get thing sorted.

12 days later the PCV also wnet West, along with sump gasket. Since this black-sludge oil issue, the oil temps have been high.

Oil wise, after trying many different brands; even Nulon 5W-40 racing oil, seems Liqui Moly 5W-40 is the best.

Basically anything that can fail in the N54 engine, has, and its been replaced. Along with a few sensors (oil temp, coolant temp, oil level).

To try and combat this oil temp issue, I've installed the following Mods:

Mishimoto - Intercooler
CSF - racing radiator (apparently 66% greater cooling than stock)
Evolution Racewerks - aftermarket oil cooler, with aluminum shroud. ER 144 cubic inches (stock was 44 cubic inches)
Stett Performance - aluminum vacuum turbo canisters
Cobb - aluminum charge pipe
Cobb - accessport sports 1+ mapping
All 6 coils
6x new spark plugs
Flushed the oil system with Seafoam.

Today... 90C coolant thermostat, along with a new electric water pump (last one replaced 36K/km previously), was installed. Thought might as well add another new EWP given the thermo change.

Indy shop claim car oil is finally cooler, after 1 hour testing of spirited driving. However, driving home (30min) with a few decent pulls, oil temp again hits 130C (266F). Hence, I'm out of pocket AU$1,366 and nothing has changed the oil temp issue.

The outside temp doesn't really make much difference.
Unless it's winter and cold 12C (53F)...well, cold for where I live. Winter nights drop to around 3C (37F).

Summer we hit temps of mid 30's (95F) to around 43C (109F).

The only thing that makes a difference is when on highway at 115km/h (71 mph). Non spirited driving on cruise control, oil temp sits around 110C (230F). But as soon as I give it the stick, it jumps to 125C (257F) or at most 130C (226F), and stay there until I return to normal driving. Even then, it take ages for the oil temp to cool. Lets say a good 10min.

One thing that is baffling me (seems odd). When I arrive home or out and the temp is hitting 130C (266F), the radiator fan always running (sound like a turbine motor under the hood). However, when I turn the engine off (when oil temp is 266F or +) the fan sometimes keeps running for a good 5min. Then other times it doesn't. That seems strange to me, given, the oil temp is at 266F or +.

After pouring close to AU$36K into this engine, I'm not only going crazy, I'm about ready for a straight-jacket, and escorted to the nut-house.

The Indy shop are useless, they're clearly clutching at straws now, which, is akin to me flushing $100 bills down the toilet S-bend.

I could sure use some help, suggestions, and or advice on what might be the hidden issue here.

Any help/input is very much appreciated guys!


Cheers

Dave

P.S. please not too techincal, I'm not mechanically minded. Though, after 3 years of this nightmare, I'm not a total newbie

 

[barry@3DM]

Sorry for the interruption guys, but I have a massive oil temp issue too. I'm in Australia, don't track the car, though, I do drive it very hard. It's a December built 2007 E93 (auto) 335i. Bought it 2'nd hand from a car-yard. While I'm not mechanically minded (all services/repairs) are done by an Indy Shop.

The car yard I bought it from, as far as I can tell, were clueless to the correct oil to use. And instead, used crap. I wasn't aware of this, until approx 3,000km later, when burnt oil smoke from OFH started to ooze from engine bay. By then, it resembled black-sludge, and had literally clogged the OFH, and stock oil cooler, along with associated piping etc. Took 3x flushes and 2x oil filters, along gasket replacements, and hoses cleaned to get thing sorted.

12 days later the PCV also wnet West, along with sump gasket. Since this black-sludge oil issue, the oil temps have been high.

Oil wise, after trying many different brands; even Nulon 5W-40 racing oil, seems Liqui Moly 5W-40 is the best.

Basically anything that can fail in the N54 engine, has, and its been replaced. Along with a few sensors (oil temp, coolant temp, oil level).

To try and combat this oil temp issue, I've installed the following Mods:

Mishimoto - Intercooler
CSF - racing radiator (apparently 66% greater cooling than stock)
Evolution Racewerks - aftermarket oil cooler, with aluminum shroud. ER 144 cubic inches (stock was 44 cubic inches)
Stett Performance - aluminum vacuum turbo canisters
Cobb - aluminum charge pipe
Cobb - accessport sports 1+ mapping
All 6 coils
6x new spark plugs
Flushed the oil system with Seafoam.

Today... 90C coolant thermostat, along with a new electric water pump (last one replaced 36K/km previously), was installed. Thought might as well add another new EWP given the thermo change.

Indy shop claim car oil is finally cooler, after 1 hour testing of spirited driving. However, driving home (30min) with a few decent pulls, oil temp again hits 130C (266F). Hence, I'm out of pocket AU$1,366 and nothing has changed the oil temp issue.

The outside temp doesn't really make much difference.
Unless it's winter and cold 12C (53F)...well, cold for where I live. Winter nights drop to around 3C (37F).

Summer we hit temps of mid 30's (95F) to around 43C (109F).

The only thing that makes a difference is when on highway at 115km/h (71 mph). Non spirited driving on cruise control, oil temp sits around 110C (230F). But as soon as I give it the stick, it jumps to 125C (257F) or at most 130C (226F), and stay there until I return to normal driving. Even then, it take ages for the oil temp to cool. Lets say a good 10min.

One thing that is baffling me (seems odd). When I arrive home or out and the temp is hitting 130C (266F), the radiator fan always running (sound like a turbine motor under the hood). However, when I turn the engine off (when oil temp is 266F or +) the fan sometimes keeps running for a good 5min. Then other times it doesn't. That seems strange to me, given, the oil temp is at 266F or +.

After pouring close to AU$36K into this engine, I'm not only going crazy, I'm about ready for a straight-jacket, and escorted to the nut-house.

The Indy shop are useless, they're clearly clutching at straws now, which, is akin to me flushing $100 bills down the toilet S-bend.

I could sure use some help, suggestions, and or advice on what might be the hidden issue here.

Any help/input is very much appreciated guys!


Cheers

Dave

P.S. please not too techincal, I'm not mechanically minded. Though, after 3 years of this nightmare, I'm not a total newbie

Have you installed an oil thermostat delete?

I haven't read through this thread but seems like lots of info there at a glance. Considering your climate and driving style you won't care about extended warm up time.

Best aftermarket oil thermostat solution for N54?

I know BMS makes the Sport Oil Cooler valve: http://www.burgertuning.com/sport_oil_cooler_valve.html I'm pretty sure this valve is simply a bypass so your oil is being cooled all the time. This can't be optimal for those who live in a cold climate or want to get up to operating temperature...

bmw.spoolstreet.com

 

[Bnks334]

Sorry for the interruption guys, but I have a massive oil temp issue too. I'm in Australia, don't track the car, though, I do drive it very hard. It's a December built 2007 E93 (auto) 335i. Bought it 2'nd hand from a car-yard. While I'm not mechanically minded (all services/repairs) are done by an Indy Shop.

The car yard I bought it from, as far as I can tell, were clueless to the correct oil to use. And instead, used crap. I wasn't aware of this, until approx 3,000km later, when burnt oil smoke from OFH started to ooze from engine bay. By then, it resembled black-sludge, and had literally clogged the OFH, and stock oil cooler, along with associated piping etc. Took 3x flushes and 2x oil filters, along gasket replacements, and hoses cleaned to get thing sorted.

12 days later the PCV also wnet West, along with sump gasket. Since this black-sludge oil issue, the oil temps have been high.

Oil wise, after trying many different brands; even Nulon 5W-40 racing oil, seems Liqui Moly 5W-40 is the best.

Basically anything that can fail in the N54 engine, has, and its been replaced. Along with a few sensors (oil temp, coolant temp, oil level).

To try and combat this oil temp issue, I've installed the following Mods:

Mishimoto - Intercooler
CSF - racing radiator (apparently 66% greater cooling than stock)
Evolution Racewerks - aftermarket oil cooler, with aluminum shroud. ER 144 cubic inches (stock was 44 cubic inches)
Stett Performance - aluminum vacuum turbo canisters
Cobb - aluminum charge pipe
Cobb - accessport sports 1+ mapping
All 6 coils
6x new spark plugs
Flushed the oil system with Seafoam.

Today... 90C coolant thermostat, along with a new electric water pump (last one replaced 36K/km previously), was installed. Thought might as well add another new EWP given the thermo change.

Indy shop claim car oil is finally cooler, after 1 hour testing of spirited driving. However, driving home (30min) with a few decent pulls, oil temp again hits 130C (266F). Hence, I'm out of pocket AU$1,366 and nothing has changed the oil temp issue.

The outside temp doesn't really make much difference.
Unless it's winter and cold 12C (53F)...well, cold for where I live. Winter nights drop to around 3C (37F).

Summer we hit temps of mid 30's (95F) to around 43C (109F).

The only thing that makes a difference is when on highway at 115km/h (71 mph). Non spirited driving on cruise control, oil temp sits around 110C (230F). But as soon as I give it the stick, it jumps to 125C (257F) or at most 130C (226F), and stay there until I return to normal driving. Even then, it take ages for the oil temp to cool. Lets say a good 10min.

One thing that is baffling me (seems odd). When I arrive home or out and the temp is hitting 130C (266F), the radiator fan always running (sound like a turbine motor under the hood). However, when I turn the engine off (when oil temp is 266F or +) the fan sometimes keeps running for a good 5min. Then other times it doesn't. That seems strange to me, given, the oil temp is at 266F or +.

After pouring close to AU$36K into this engine, I'm not only going crazy, I'm about ready for a straight-jacket, and escorted to the nut-house.

The Indy shop are useless, they're clearly clutching at straws now, which, is akin to me flushing $100 bills down the toilet S-bend.

I could sure use some help, suggestions, and or advice on what might be the hidden issue here.

Any help/input is very much appreciated guys!


Cheers

Dave

P.S. please not too techincal, I'm not mechanically minded. Though, after 3 years of this nightmare, I'm not a total newbie

266f is not terrible... As stated, there is coolant temp logic in play that might affect how hot the oil gets on the street. It's really hard to judge these things on the street. If you run MHD race coolant logic I bet you'll see lower oil temps. With stock settings my car would hover around 240-250f. Doing a few pulls would get it up to 260f. With race settings targeting lower coolant temps my oil on the street sits closer to 210-220f which is basically the bottom end of the oil thermostats operating range. The oil cooler is usually ice cold.

 

[MDORPHN]

FWIW, before I added a large 34-row Setrab oil cooler, I'd regularly see 280-290F on hot days when driving on track.

Neil

 

[fmorelli]

Tough advise to type, and not about cooling: I'd consider selling the car. If you drive it hard, at least the turbos are next on the list, especially with the oil issue (which was at least a previous owner problem, not a yard problem by my estimation). Sorry to say that, as I know it has been a long road, but I'd be unhelpful if I didn't suggest that consideration. If you hold on to it, I hope fortune turns to where you're not constantly shoveling money into the car.

Filippo

 

[Asbjorn]

Have you installed an oil thermostat delete?

I haven't read through this thread but seems like lots of info there at a glance. Considering your climate and driving style you won't care about extended warm up time.

Best aftermarket oil thermostat solution for N54?

I know BMS makes the Sport Oil Cooler valve: http://www.burgertuning.com/sport_oil_cooler_valve.html I'm pretty sure this valve is simply a bypass so your oil is being cooled all the time. This can't be optimal for those who live in a cold climate or want to get up to operating temperature...

bmw.spoolstreet.com

I wouldn't recommend deleting the engine oil thermostat. I ended up putting mine back in. Deleting it makes zero difference on track. However, on the street oil temps will stay way below 100C in winter which isn't good.

@DaveAU335i

I agree with what others have said. 130C is non-issue for engine oil. Nothing to worry about.

 

[NoQuarter]

Tough advise to type, and not about cooling: I'd consider selling the car. If you drive it hard, at least the turbos are next on the list, especially with the oil issue (which was at least a previous owner problem, not a yard problem by my estimation). Sorry to say that, as I know it has been a long road, but I'd be unhelpful if I didn't suggest that consideration. If you hold on to it, I hope fortune turns to where you're not constantly shoveling money into the car.

Filippo

I was thinking the same thing when I got to your post. There is no oil bad enough that the yard could have put in it to do what was described. For someone begging to not talk technical and paying for ALL service, this car is going to be an even bigger money pit.

 

[MDORPHN]

I deleted the stock oil thermostat and went with an external Improved Racing 190F thermostat.

Neil

 

[Asbjorn]

I deleted the stock oil thermostat and went with an external Improved Racing 190F thermostat.

Neil

Wouldn't it be wiser to run a 220F racing thermostat? I would be concerned if my engine oil temperature rarely exceeded 190F.

 

[DaveAU335i]

Have you installed an oil thermostat delete?

I have tried that, wasn't sure which one to purchase (red or blue) so got both. Turned out to be the Red one. Made absolutely no difference from the stock spring OFH thermostat. Which, TBH, seemed strange, give all the mods had been added at that stage.

The Indy shop tried to say, the oil was going thru the Racewerks cooler too quickly (due to thermo delete), and it wasn't staying long enough in said RW cooler to be cooled. Sounded more like an excuse than a real point of reference. Thing is though, when the stock thermo was reinstalled, nothing changed.

Left out I also had a walnut blast 4K km ago, and the injectors were replaced by recall. The only thing I can come up with now, I'm wondering if the oil is not flowing freely thru the oil system. The Seafoam should have cleaned the Galleries and Spurters. But I';m not entirely au fait with what else, or where else the oil cooling system traverses thru the engine, and back thru the cooler.

NB - about 7,000km ago, replaced ALL 4 coolant turbo lines (very subtle leak)

I'm aware that the OFH has a plate on its underside, which, apprently transfers oil heat, to coolant, which sits directly under the transfer plate. But I don't think the coolant system is the issue. Instead, I keep coming back to an issue with the oil cooling system itself.

Aside from the sensors I've replaced (oil level temp: sump, oil temp: rear top of OFH, and coolant temp sensor: back rear bottom side of OFH), are there any other sensors which govern oil temps, and or measure oil temp, and correspond with radiator fan operational speeds?

I'm starting to wonder if the "fan" is cactus, given it's random, continued activation after engine is switched off. If the fan isn't corresponding to ECU instructions (or whatever operates the fan % spin), then that would certainly be a big factor in cooling. Yes/No?

EG - if the fan isn't running till the temp hits 130C (266F) then nothing other is going to cool the oil. The fact on highway driving the raidator is receiving sufficient cool airflow to keep it at 110C (230F), unless I hammer it, the oil temp rises dramatically. But, when returning to normal driving, the oil temp does return to 110C (230F) albeit after 5min of high flow highway driving. Which to me, suggests that maybe the fan is dodgy...


Edit:

How would one go about testing the oil pressure? If there is a block someplace, then the oil pressure (I would assume) depending on where the test was conducted, would show different oil pressure readings???

The other option, is visit the Cobb Accessport distributor here, and he can connect the pro program to the ECU, and force the EWP to run constantly at 100%. That should drop temps. But if it doesn't, then maybe, as I mentioned, the fan is cactus.

 

[bantam]

The radiators (aftermarket included) are tiny in these cars. Its because of the big ass fan and the FMIC. They limit core thickness and frontal surface area respectively.

The fan is so thick you can't put a thicker core radiator in, at least not a PnP one. Next, because of the FMIC being located under the radiator, the radiator is too short which kills frontal surface area.

Unfortunately Increasing frontal area will be difficult as it will likely require a custom FMIC. Increasing core thickness is much more doable. By removing the fan and replacing it with a thinner fan, the core thickness can be increased a lot, possibly up to 2"s thick. The issue to overcome is the backside of the radiator and FMIC are flush and they use one fan for both. This can be overcome by either ducting or using multiple fans, one on the radiator and small ones on the FMIC.

Barry,

Considering your efforts to build a legitimate race car, it would not be exceptionally difficult to fit the s55 charge cooler into your car and get a custom longer radiator, then use a charge air radiator that is large and flat.

 

[barry@3DM]

Barry,

Considering your efforts to build a legitimate race car, it would not be exceptionally difficult to fit the s55 charge cooler into your car and get a custom longer radiator, then use a charge air radiator that is large and flat.

Not sure I follow 100%...

You are saying "retro fit" the s55 intercooler to allow me to use a longer radiator. I'm not sure what you mean by "then use a charge air radiator that is large and flat."

 

[bantam]

Not sure I follow 100%...

You are saying "retro fit" the s55 intercooler to allow me to use a longer radiator. I'm not sure what you mean by "then use a charge air radiator that is large and flat."

I suppose that may be an odd way of explaining it, but essentially just mimic the s55 setup, no more charge cooler underneath the radiator limiting your frontal area.

In this case, since the limiting factor is room for coolers, you should be able to gain something by changing to the water to air arrangement (water to air can reject more heat per unit of radiator volume than air to air)