4.6 supercharged..... oil cooler required?
Discussion
Hi everyone.
The megasquirt project rolls on.
We are most likely going to supercharge this car next year, and given that a supercharged 4.6 ought to do about 350HP, I would imagine the oil will get a bit toasty with the extra power being developed and the fairly unimpressive thermodynamic efficiency of a petrol engine...
Should I plan to be putting an oil cooler in? And thus pop the requisite wires in the harness for the temperature sensor on the hot side of the cooler?
What say you, Pistonheads?
Ed.
The megasquirt project rolls on.
We are most likely going to supercharge this car next year, and given that a supercharged 4.6 ought to do about 350HP, I would imagine the oil will get a bit toasty with the extra power being developed and the fairly unimpressive thermodynamic efficiency of a petrol engine...
Should I plan to be putting an oil cooler in? And thus pop the requisite wires in the harness for the temperature sensor on the hot side of the cooler?
What say you, Pistonheads?
Ed.
The answer would depend on what you're doing with the car really.
On a UK road car you're on boost so little of the time that your oil temps won't be too dis-similar to a normal TVR. I like to keep things simple so if it was me I'd just be using a good quality synth oil and wouldn't bother with an oil cooler.
If you plan long continental journies, or plan on doing track days then a cooler would probably help, but for 99 percent of people in the UK in a similar situation an oil cooler probably isn't worth bothering with.
I don't really see much point unless you're thrashing it regularly for a long time.
On a UK road car you're on boost so little of the time that your oil temps won't be too dis-similar to a normal TVR. I like to keep things simple so if it was me I'd just be using a good quality synth oil and wouldn't bother with an oil cooler.
If you plan long continental journies, or plan on doing track days then a cooler would probably help, but for 99 percent of people in the UK in a similar situation an oil cooler probably isn't worth bothering with.
I don't really see much point unless you're thrashing it regularly for a long time.
As for intercooling, that depends what you hp levels and boost will be, but for most road cars running up to say 6 or 7 psi I'd for-go the intercooler too.
I see more issues with cars running intercoolers poorly sited , compromising the water cooling, and in fact not ducted properly so the through-air of the intercooler isn't that great anyway.
If you're going to run any sort of additional cooling make sure it's properly ducted front AND back from high pressure to low pressure, and doesn't compromise the water cooling rad. If you can't do that adequately I think you're better off not having any additional cooling at all, and eliminate any potential issues you're going to create by doing it badly ..
I see more issues with cars running intercoolers poorly sited , compromising the water cooling, and in fact not ducted properly so the through-air of the intercooler isn't that great anyway.
If you're going to run any sort of additional cooling make sure it's properly ducted front AND back from high pressure to low pressure, and doesn't compromise the water cooling rad. If you can't do that adequately I think you're better off not having any additional cooling at all, and eliminate any potential issues you're going to create by doing it badly ..
OK, thank you folks.
The car WILL do sprints, hill climbs and occasional trackdays. Based on what has been said by those with experience, I'm minded to fit an oil cooler - I had assumed that we would be intercooling the charge air anyway, and I note the point about doing it CORRECTLY.
I'll do some reading on ducting of intercoolers. There is a decent amount of room in the nose, but the coolant will be transporting a lot more heat with a charger too, so that needs to not be neglected. It is interesting that the fan cowling on the rear face of the rad effectively blanks off a large area of the core to airflow..................
Anyhoo, thanks, folks.
Ed.
The car WILL do sprints, hill climbs and occasional trackdays. Based on what has been said by those with experience, I'm minded to fit an oil cooler - I had assumed that we would be intercooling the charge air anyway, and I note the point about doing it CORRECTLY.
I'll do some reading on ducting of intercoolers. There is a decent amount of room in the nose, but the coolant will be transporting a lot more heat with a charger too, so that needs to not be neglected. It is interesting that the fan cowling on the rear face of the rad effectively blanks off a large area of the core to airflow..................
Anyhoo, thanks, folks.
Ed.
I'm gonna go electric with the oil temp sensor but it will be a proper Honeywell one, so it'll be accurate, and the display will be LCD in place of the stereo.
I've written most of the code - it uses a Mega2560 uC and a CANbus interface to read whatever parameters are of interest from the ECU, and anything not on the CANbus directly from the sensors. Each sensor is individually calibrated (I'm not UKAS certified, mind, just me and my cooker, a thermocouple and a pan of water!) and the display is digitally driven. In some ways it'd be nice to have a stepper motor driven gauge, but I don't want to hack about with the dash too much.
I guess the old debate about where to put the sensor rears its head. I note your point about putting it in the sump - I guess the oil is at its hottest just after its been sheared half to death in the bearings, so perhaps the sump is the pace to measure the temp...
I've written most of the code - it uses a Mega2560 uC and a CANbus interface to read whatever parameters are of interest from the ECU, and anything not on the CANbus directly from the sensors. Each sensor is individually calibrated (I'm not UKAS certified, mind, just me and my cooker, a thermocouple and a pan of water!) and the display is digitally driven. In some ways it'd be nice to have a stepper motor driven gauge, but I don't want to hack about with the dash too much.
I guess the old debate about where to put the sensor rears its head. I note your point about putting it in the sump - I guess the oil is at its hottest just after its been sheared half to death in the bearings, so perhaps the sump is the pace to measure the temp...
I saw 115 degrees oil temperature at the TVRCC track day using 2.5 psi of boost (325 bhp at full chat), 4.6 turbo Chimaera.
Turned it up to 7.5 psi (395 bhp max) for one lap and the oil temperature immediately shot up 10 degrees.
That's with fully synth 10w60 oil, a properly sited intercooler and a small oil cooler behind the slots bottom right as you look at the car from the front.
IMHO, any track activity with a turbo you need all the cooling you can get.
I have no opinion on supercharging - common sense says it will run a bit cooler, as you don't have that bloody hot lump of turbo right in the front of the engine bay.
Turned it up to 7.5 psi (395 bhp max) for one lap and the oil temperature immediately shot up 10 degrees.
That's with fully synth 10w60 oil, a properly sited intercooler and a small oil cooler behind the slots bottom right as you look at the car from the front.
IMHO, any track activity with a turbo you need all the cooling you can get.
I have no opinion on supercharging - common sense says it will run a bit cooler, as you don't have that bloody hot lump of turbo right in the front of the engine bay.
Hmmmmm, coooooooooling….
I've got a Peltier cooler sitting on my desk and I'm desperate to use it. Problem is the amount of electrical power required and hence I^2R heating would probably more than equal the amount of heat I can get out of the oil!!
"Yeh the oil's nice and cool but the alternator just melted...!"
So I think a decent sized cooler in a clever location is needed. I heed the point about the oilstat - that is sensible because I do want to be able to bake out the oil so it needs to reach 100c regularly.
I've got a Peltier cooler sitting on my desk and I'm desperate to use it. Problem is the amount of electrical power required and hence I^2R heating would probably more than equal the amount of heat I can get out of the oil!!
"Yeh the oil's nice and cool but the alternator just melted...!"
So I think a decent sized cooler in a clever location is needed. I heed the point about the oilstat - that is sensible because I do want to be able to bake out the oil so it needs to reach 100c regularly.
Here is a picture taken of my car a few years ago. You can see the large oil cooler on the left of the radiator.
The position of the oil cooler does not affect the water cooling, (aluminium radiator).
Since then, the carbon fibre splitter has been opened up in front of the vents in the front valance.
The air filter has also been repositioned out the way in the inner wing nearside.
The position of the oil cooler does not affect the water cooling, (aluminium radiator).
Since then, the carbon fibre splitter has been opened up in front of the vents in the front valance.
The air filter has also been repositioned out the way in the inner wing nearside.
Boosted LS1 said:
You could fit a thermostat to the oil cooler. A capillary guage in the sump is a must imo.
That's what I did. Capillary gauge in sump and used twin oil coolers mounted upright either side of intercooler with no problems, no overheating on continent in heatwave nor up through Alps. I added vents to front and at exit and remote oil filter so as to keep the original size and was also easier to change. No doubt someone will tell me I was wrong 
Edited by macdeb on Friday 19th July 17:49
Edited by macdeb on Friday 19th July 17:52
That is indeed very tidy! The sort of thing I aspire to.
The other thing I really like about Mac's car is that the oil hoses are properly fabricated with swaged fittings rather than bloody jubilee clips. Thank you all for your opinions, help, guidance etc.
I suppose the only thing that makes me groan about oil cooler is the weight. I wonder if I can get a front cover without the filter housing: just a pair of oil ports....... That'd be a start - I like things to NOT look adapted.
Hmmmmmmmmmm........
The other thing I really like about Mac's car is that the oil hoses are properly fabricated with swaged fittings rather than bloody jubilee clips. Thank you all for your opinions, help, guidance etc.
I suppose the only thing that makes me groan about oil cooler is the weight. I wonder if I can get a front cover without the filter housing: just a pair of oil ports....... That'd be a start - I like things to NOT look adapted.
Hmmmmmmmmmm........
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