[apk919]

Yes, of course I saw the schematic - the temps from both sensors are plugged into the ECU according to the schematic - correct? Even if the IAT is from the MAF I should still be able to use the correct lead (i.e. the "NG" colored one) from the TMAP to control the IC fans as several have done previously in this thread...
-john.

Sorry, I wasn't sure if you'd seen the earlier post. If the temperature sensor of the TMAP is not used at all, then I suppose you could tap into it without causing any other issues...

EDIT: If I'm reading the Bosch spec sheet properly, it's a thermistor and not a thermocouple. I think that actually makes it easier to deal with for making a fan controller than a thermocouple.

 

[ocelot27]

Sorry, I wasn't sure if you'd seen the earlier post. If the temperature sensor of the TMAP is not used at all, then I suppose you could tap into it without causing any other issues...

EDIT: If I'm reading the Bosch spec sheet properly, it's a thermistor and not a thermocouple. I think that actually makes it easier to deal with for making a fan controller than a thermocouple.

Yeah - the Spal controller is really cool - will read just about any signal - you just tell it at what voltages to turn on and off.... and it's dynamic fan control!
-john.

 

[EricH]

I downloaded the manual and service notes back in February... it included a lot of '08 updates, including '08 schematics, launch control, new instrument panel, etc.

Just for a point of reference, I just got my hardcopy of the manual a few weeks ago. It did not include '08 info. (yet?) The dealer told me that as updates are released they will be sent to me.

 

[apk919]

I downloaded the manual and service notes back in February... it included a lot of '08 updates, including '08 schematics, launch control, new instrument panel, etc.

Just for a point of reference, I just got my hardcopy of the manual a few weeks ago. It did not include '08 info. (yet?) The dealer told me that as updates are released they will be sent to me.

I should have been more specific... I meant the service manual, not the owner's manual. I'm assuming you mean the owner's manual?

Frankly, for anyone who does any work on the car themselves, it's well worth the $25 to download the service manual and bulletins... you can always print out pertinent pages, bring them to the garage, scribble notes on them, etc.

 

[Mag]

Luckily not much work. The RLS IC I have is the WI one and the thermocouple probe fixture happened to be the same thread (retapped earlier).

apk919, if my data is correct, I'm afraid you are correct! Time for me to download that manual.

So I ran the data. Warning. Not going to like what you see.

Notice somthing grossly wrong here? Post IC is consistantly higher than Pre... accept when the car is at high speeds, where yellow line starts to drop off below the violet line. this was at 100mph. Got flow? rotfl

When I first connected the Post IC prob, car had had the probe in the IC during idling period, there after cooled off in the IC. Pulled it out and checked temps at 31, verified with infrared. Ambient 23C. After the log run, again pulled out the post IC prob out of the IC, and sure enough temps dropped from 60C to 33, which intuitively makes sense having been heated up by air and oil blow by.

Typhoon storm tonight so a bit cooler than last time. Windy. So interestingly, when the car was still or slow moving roof temps were on par with ambient, 27C versus 23C, but with the car jamming, temps rise to 30C therebouts.

Note: both probes used are same brand, both new, wire same length, run side by side, plugged into same device, which was calibrated just before the run.

Theories why it's so hot on outlet side... heat soak from SC is my guess. May be this is why the TMAP IAT is kept where it's at.

 

[robains]

Could I get a link to where I can download/purchase the Lotus Exige S service manual and TSB? Is this a service manual or a shop manual?

I'm used to paying $300 for shop manual downloads.

Thanks, Rob.

 

[Mag]

Here's the same chart with the TMAF IAT. (Sorry about the fancy font, mislabeled the chart in excel and used photobucket to paste correct name, no way of changing it.)

Will be very intersting to see the stock IC data.

 

[Smoky]

Sweet data. Depressing, but great to see it logged.

Wondering if the rls i/c made the condition "less worse" than with the oem i/c.

Hook up some fans to that thang, and rerun that test. See if it helps! Cuz from your data it looks like the best upgrade is just to get rid of the i/c!! lol That doesn't seem right, but data doesn't lie (it can be wrong, but it never lies).

 

[Mag]

Sweet data. Depressing, but great to see it logged.

Wondering if the rls i/c made the condition "less worse" than with the oem i/c.

Hook up some fans to that thang, and rerun that test. See if it helps! Cuz from your data it looks like the best upgrade is just to get rid of the i/c!! lol That doesn't seem right, but data doesn't lie (it can be wrong, but it never lies).

well Im almost hoping i messed something up and the data is wrong...cos my guess is it's going to take a lot more than 2 little fans to get similar flow to what's coming through that hole at 100mph.

Data might be the hotter at the TMAF temp with no IC. If it is heatsoak, reckon it would travel and make it's way to the TMAF temp area with out the IC in place. I might just end up ditching the hatch, lengthening the tubes and brackets, make an IC spoiler like the mitsubishi posted on another thread on this forum if it comes to it.

i will run a test with the stock IC and another with fans in the RLS set up. Hope I can get enough time to do this soon, but with equity markets looking a lot like the charts posted above (yes Im a banker wanker), and my gf's family in town in a couple days... but i like challenges, especially dangerous ones. :sheep:

 

[Illumiloti]

This is why I went with a water/ air chargecooler. There is simply no way to get enough air through that mail slot of a roof/ clam to effectively cool the charge. (no matter how much fettling of the clam you do, the roof opening going into the clam is what it is). The RLS is a bigger/ "more efficient" intercooler but it can only be as efficient as the air flow through it. Are you going to test with water/ meth injection? That would, I'm sure, make a big improvement.

 

[apk919]

Could I get a link to where I can download/purchase the Lotus Exige S service manual and TSB? Is this a service manual or a shop manual?

I'm used to paying $300 for shop manual downloads.

Thanks, Rob.

Here's the link: Lotus Subscriber - Log-in

This link is for buying a new "subscription": http://lotustechinfo.com/subscriber_new.asp

 

[Mag]

Time Scale

Note the data was taken over a period of 14mins approx. First 5mins was warm up.

Each spike represents a significant duration where the car was getting pushed. the set of high spikes represent the highest speeds over the entire sample.

 

[Mag]

This is why I went with a water/ air chargecooler. There is simply no way to get enough air through that mail slot of a roof/ clam to effectively cool the charge. (no matter how much fettling of the clam you do, the roof opening going into the clam is what it is). The RLS is a bigger/ "more efficient" intercooler but it can only be as efficient as the air flow through it. Are you going to test with water/ meth injection? That would, I'm sure, make a big improvement.

Water injection, yes. But the "true" location of the IAT has gotten me wondering. I'm thinking it would improve if one could get the post water injection charge to resemble that of the TMAF IAT. I guess it couldnt do any harm as the charge would prob never get cooler than TMAF IAT's.

May be this is one reason besides aerodynamics/weight savings, the 211 IC location is where the trunk is... but then again, on the flipside, this is near the exhaust manifold.

On a side note: Wonder how much contribution the return head cylinder gasses have to do with the temps at the TMAF IAT. If it's significant, catch 22, might lower the temps at the IAT to change timing in a way thats not combustion efficient under the assumption that post IC temps may not drop in proportion.

 

[apk919]

Luckily not much work. The RLS IC I have is the WI one and the thermocouple probe fixture happened to be the same thread (retapped earlier).

apk919, if my data is correct, I'm afraid you are correct! Time for me to download that manual.

So I ran the data. Warning. Not going to like what you see.

Notice somthing grossly wrong here? Post IC is consistantly higher than Pre... accept when the car is at high speeds, where yellow line starts to drop off below the violet line. this was at 100mph. Got flow? rotfl

When I first connected the Post IC prob, car had had the probe in the IC during idling period, there after cooled off in the IC. Pulled it out and checked temps at 31, verified with infrared. Ambient 23C. After the log run, again pulled out the post IC prob out of the IC, and sure enough temps dropped from 60C to 33, which intuitively makes sense having been heated up by air and oil blow by.

Typhoon storm tonight so a bit cooler than last time. Windy. So interestingly, when the car was still or slow moving roof temps were on par with ambient, 27C versus 23C, but with the car jamming, temps rise to 30C therebouts.

Note: both probes used are same brand, both new, wire same length, run side by side, plugged into same device, which was calibrated just before the run.

Theories why it's so hot on outlet side... heat soak from SC is my guess. May be this is why the TMAP IAT is kept where it's at.

I guess I'm surprised that the outlet side of the IC is consistently hotter than the inlet side (except at high speeds)... even with no flow the IC must be radiating some heat? Why at time "0" is the post IC temp ~55C and the pre IC temp ~30C? Was the IC already heat soaked? It doesn't make sense that the charge is hotter after the IC than before... what's heating it up again? The engine compartment is not 55C, is it? I'm wondering if the probes are measuring the temperature of the metal surfaces, and not the temperature of the charged air?

OK, too many questions... I've got to take a little time to digest your data... it's certainly not what I expected to see!

EDIT: If you don't mind Mag, could you PM or email the session log to me? I'd love to see what's happening in those short bursts of boost...

EDIT2: You beat me to it... thanks!

 

[Mag]

I guess I'm surprised that the outlet side of the IC is consistently hotter than the inlet side (except at high speeds)... even with no flow the IC must be radiating some heat? Why at time "0" is the post IC temp ~55C and the pre IC temp ~30C?

car had cooled down from previous idle, for about 2 hours. Time zero occured after cool down and about a minute during which the car was pulled out of the driveway and I could hit the log record button. Prior to engine start, the temps post IC was mid 30's. Which wouldn't be too suprising.

Was the IC already heat soaked?

partially warmed up at time zero.

It doesn't make sense that the charge is hotter after the IC than before... what's heating it up again? The engine compartment is not 55C, is it?

I have measured the TMAp postion with an infrared temp gun after driving previous to tonight and it is at mid 50Cs. May be cos the TMAF IAT is much farther away with rubber airbox outlet/TB between it and the SC as opposed to the post IC temp probe location.

I'm wondering if the probes are measuring the temperature of the metal surfaces, and not the temperature of the charged air?

I made sure the probe on the post IC side wasn't touching anything (bars/fins in core) and positioned somwhere in the center before the outlet coupling on IC.

Fixture is brass or copper I think and came as a kit with the probe. The pre IC side probe is exactly the same.

OK, too many questions... I've got to take a little time to digest your data... it's certainly not what I expected to see!

yes please do. I have got to go to bed, hope to read on further analysis over breakfast opcorn:

 

[robains]

Your data is about what I expected. And I agree, fans on the IC will not help -- fans in a race car are only used when there is no air flow (aka not driving at speed) -- when racing (if you have fans) you turn them off, only when you come into pits or doing cool down laps do you turn the fans back on (aka low speed).

Does anyone have a charge cooler? Would be nice to get their numbers -- but my hunch is that a charge cooler's benefit is with more stability and consistant temps under load and non-load situations -- I don't think it would necessarily reduce the air/gas mix tempurature that ultimately goes into the cyclinder chamber.

 

[apk919]

car had cooled down from previous idle, for about 2 hours. Time zero occured after cool down and about a minute during which the car was pulled out of the driveway and I could hit the log record button. Prior to engine start, the temps post IC was mid 30's. Which wouldn't be too suprising.

partially warmed up at time zero.

Wow, if the IC itself is at 55C after a minute or so of idling, that's bad.

I have measured the TMAp postion with an infrared temp gun after driving previous to tonight and it is at mid 50Cs. May be cos the TMAF IAT is much farther away with rubber airbox outlet/TB between it and the SC as opposed to the post IC temp probe location.

55C is 131F, which is where temps behind the IC went a minute or so after shutting down the engine during my data log. But while I was driving, even sitting still, the air in the engine compartment didn't exceed 115F (46C)...

I made sure the probe on the post IC side wasn't touching anything (bars/fins in core) and positioned somwhere in the center before the outlet coupling on IC.

Fixture is brass or copper I think and came as a kit with the probe. The pre IC side probe is exactly the same.

I'm just grasping for straws... I don't want to believe the IC is that hot...

yes please do. I have got to go to bed, hope to read on further analysis over breakfast opcorn:

I'm going to load all this up on my laptop... I'm traveling later tonight, so I'll have something to keep me busy if the in-flight movie sucks...

 

[EricH]

I should have been more specific... I meant the service manual, not the owner's manual. I'm assuming you mean the owner's manual?

Actually I should have been! I was talking about the service manual.

 

[Smoky]

Obviously the charge cooler is "the" solution to lower temps.

Unfortunately the current chargecooler offering is way too expensive and way to difficult for the average enthusiast to install. And since not everyone lives down the road from a top-notch Lotus aftermarket specialist, it is just plain out of reach for the majority. I've even read a few complaints that the chargecooler isn't doing that great a job either, as well as complaints that the chargecooler radiator prevents the primary radiator from receiving the cooling air it needs to do the job of releasing heat from the coolant.

If someone would introduce a production (ie. not "one-off") chargecooler system that was completely contained and installed in the engine bay, THEN we'd really have something.

Until such a product arrives, just saying "use a chargecooler" is a cop-out. I'm much more interested in this research towards air-to-air cooling. We're not saying air-to-air will ever produce BETTER results than water cooling, but the search for the most OPTIMIZED air-to-air cooling is what we're after. It is obvious the OEM solution is not optimized. That's the goal, IMHO.

 

[apk919]

...

Until such a product arrives, just saying "use a chargecooler" is a cop-out. I'm much more interested in this research towards air-to-air cooling. We're not saying air-to-air will ever produce BETTER results than water cooling, but the search for the most OPTIMIZED air-to-air cooling is what we're after. It is obvious the OEM solution is not optimized. That's the goal, IMHO.

And that was my goal in creating this thread as well... between roof scoops, side scoops, ductwork, a/a intercooler design, I wanted to understand (through actual measurements, not assumptions) what the performance of the stock set up is, and what can be done to improve it. I feel as if I've only begun to explore the issue...