2008 Lotus Exige-S 240
Smoky & apk919 :clap:
I have Mag's latest data too... I haven't gone through it yet, but that's a graph I'd like to see (and will post if it's feasible).I found the ic does heat up quickly at idle, but then it cools down fast once you're driving and on load is when it actually makes a difference.
can you plot rpm/load along with the data too?
For the life of me i can't find my datalog from LA to LV, i'll have to make another one!
Assuming the water to air has a sufficient heat exchanger and pump, why would this happen? The engine water temps are kept at a constant level with a properly functioning system, why wouldn't the same apply to a water/ air intercooler utilizing the same principles?I also think this will work better than an air/water IC - same soak issue with this solution only it just takes longer to saturate the systems water volume with heat - better just to blow the heat right the hell out of the engine bay with big fans.
It seems as though the only temps exposed in OBD-II OEM mode are IAT (which I think is taken from the TMAF, not the TMAP), and engine coolant temperature. At this point I'm not up to hacking into the ecu... :bow:they're hooked up but it splits the function between the two, so temp on one, airflow on the other.
unfortunately lotus disabled the can bus diagnostics on the later firmwares, so you're out of luck, i'm not sure if its exposed on the obd ii oem mode or not.
Oops, I meant Global OBD mode... (at least that's what it's called on my reader). The reader has specific code for most OEM's, but of course not Lotus.OEM mode is the secret manufacturer specific one, not the standard IAT PID.
Cool, thanks.i'll take a look when i get 5 minutes.
Every time you transfer heat from one medium to another you loose efficiency. Going from air to aluminum to water to aluminum to air is much less efficient than going from air to aluminum to air... if the air your using for cooling is about the same temp. So, ultimately, it is the mass air flow over the heat exchanger and the temperature difference that determines how much heat can be removed - regardless of which method you use.Assuming the water to air has a sufficient heat exchanger and pump, why would this happen? The engine water temps are kept at a constant level with a properly functioning system, why wouldn't the same apply to a water/ air intercooler utilizing the same principles?
yes i think air to air is the way to go for a street car... but we need air. the gt3 race cars are water systems but who knows how they set up the 2 seperate water systems cooling upfront (or on sides even). Not something I think we can replicate. Even if it could be replicated, as smokey commented, the two systems would be completely different animals in terms of cost, vehicle configuration ... etc etc. Change one thing, it'll affect another and the horsesies on the merry go round and round....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.
"the water to air has a sufficient heat exchanger and pump"Assuming the water to air has a sufficient heat exchanger and pump, why would this happen? The engine water temps are kept at a constant level with a properly functioning system, why wouldn't the same apply to a water/ air intercooler utilizing the same principles?
Exactly - you still have to get rid if the heat using air so why not just use air to start with and eliminate the inefficiencies of multiple heat transfers; you may need lots of air, however (we need to know how much)."the water to air has a sufficient heat exchanger and pump"
Water transfers heat better:
Here, water has a sizeable advantage—its specific heat capacity of 4.184 J/gK is more than four times higher than air's 1.005 J/gK. Water looks even better when we consider thermal conductivity, which describes a material's ability to conduct heat. Thermal conductivity is measured in watts per meter Kelvin, and again, higher values are better. Water's 0.6062 W/mK thermal conductivity dwarfs that of air, whose thermal conductivity is only 0.0262 W/mK.
I think ultimately using water2air exhanges the volume of air that passes the an air2air system with a fixed volume of water. On a normal air to air with access to flow, the ambient temp air is limitless. In a water system, it's recycled and it would take a lot of water to replicate the same consistent ambient temp'd water. How to get rid of that transfered heat?
On an engine coolant system, the ambients are far lower than target water temps so this might be one reason this kind of system works well.
charlie... May I ask: does that mean the OEM mode is reading for the intake charge pre-intake manifold via TMAP temp sensor? If not is there another sensor we dont know about... or is the ECU using an offseting formula to get the IC outlet charge temp? - thanksOEM mode is the secret manufacturer specific one, not the standard IAT PID.
i'll take a look when i get 5 minutes.
OK, that makes sense to me... I was a bit suspicious of that...guys... think i jumped the gun on this. This lotus is kind of like my own personal home study project. My other cars are under the care of a tuner. Asked him about the readings showed him the graph. To which he replied: the way my therocouples are set up now, it's taking the temperature of the pipe itself. this is for both pre/post IC. So it makes sense post is hotter as it's closer to the SC in terms of materials between.
I need to make a gasket out of Bakelite for the sensors between the pipe and the copper fixture for the thermocouple probe.