Si's second attempt at a DC2


Nice to see a build thread still going these days :nice:
 
Regarding oil, I'm still on oem laminova and using 5w40 ester race oil. I'm able to do 45minutes flat out at Rockingham and still staying just under 120 degrees constant with no issues.
I was able to drop 10 degrees in comparison to normal 5w40 fully synthetic.
Personally I feel there's no need for a external cooler with the right setup.
Hope this helps

I've been running Fuchs Titan Pro S in 5W40 which is ester but fully synthetic.
I don't know what it is about my car but its running way too hot for some reason. I even have heat barrier tape between the sump and exhaust manifold. T.he gauges are brand new so no reason it should be a false reading.

I accidentally didn't notice the gauge on one of my sessions at combe and it was reading 140degrees before I clocked it! I'd only been out about 10 minutes as well.
I know thats pushing it, and could have caused damage to the engine if I continued.
But at those temps you can't tell me there's no need for a oil cooler?
 
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I've been running Fuchs Titan Pro S in 5W40 which is ester but fully synthetic.
I don't know what it is about my car but its running way too hot for some reason. I even have heat barrier tape between the sump and exhaust manifold. T.he gauges are brand new so no reason it should be a false reading.

I accidentally didn't notice the gauge on one of my sessions at combe and it was reading 140degrees before I clocked it! I know thats pushing it, and could have caused damage to the engine if I continued.
But at those temps you can't tell me there's no need for a oil cooler?
Previously on normal 5w40 I would hit 130 degrees within 20mins, which also got me concerned and got me to do a lot of research from this forum and testing to eliminate the issue. Only oil was changed for ester which made a huge difference for me. All my cooling was stock including radiator etc, i even used 3 gauges to make sure that everything read right and they all backed up each other. I guess all our engines work differently and there's no right or wrong and go for what works best for you.
 
Previously on normal 5w40 I would hit 130 degrees within 20mins, which also got me concerned and got me to do a lot of research from this forum and testing to eliminate the issue. Only oil was changed for ester which made a huge difference for me. All my cooling was stock including radiator etc, i even used 3 gauges to make sure that everything read right and they all backed up each other. I guess all our engines work differently and there's no right or wrong and go for what works best for you.

Yeah testing is all I can do until I find a solution. May need a cooler may not. Yeah I'm on stock radiator etc, but my coolant has never got above 95.
Only thing I want to change possibly is to take the oil temp reading from the sump. I'm not too keen on drilling into a spoon sump though :nerv: haha
 
Yeah he done my rocker and strut brace years back, he does some top quality work!
 
Yeah testing is all I can do until I find a solution. May need a cooler may not. Yeah I'm on stock radiator etc, but my coolant has never got above 95.
Only thing I want to change possibly is to take the oil temp reading from the sump. I'm not too keen on drilling into a spoon sump though :nerv: haha
Taking temps from the sump leaves less margin for error and warning, down to preference.
If you haven't already I would suggest checking over your whole oem cooler system to make sure everything is in order and eliminate every other component that works with cooling etc.
Simple things are easy to miss,
All the best.
 
I've been back a week and already want to go back! :beer: haha

Regarding the oil, this was advised to me after a lengthy chat with Opie Oils. What I will most likely do is run this oil for a while until I get the cooler sorted then change back down to 10W40. Will see how the car behaves with the different oils.

Where the 5W40 is so thin I'm getting up to 120degrees within about 2 laps of Combe. Annoyingly going around the Ring I was having to ease off and coast the car in places as the oil way getting way too hot.

Not particularly I don't think, he hit a bump in the road whilst turning, causing the rear end to go light which gave him some understeer, but he couldn't correct it in time.
My mates Go Pro video from the JDM EP3, you can see him go sideways around the corner from the rear view mirror and then disappear.

Think the worst thing is none of the airbags even went off! :shocked:


I’ve seen a few oil experts talking about the same subject and they were explaining that thinner oil actually takes heat out of an engine more efficiently than thicker oil

I run a 280hp DC2 with close gearing in 20min races using 5w40 Ester synthetic oil up to 130degrees without any issues, I’ve only fitted an oil cooler recently and temps don’t go above 110... 120 should not give any problems with good oil... up at 130 you would want an external cooler but you know that anyway


It’s a very unforgiving circuit which is why we took it easy enough out there but even at a medium pace there is still a risk of a bad accident... I suppose if it wasn’t dangerous it wouldn’t seem like as much of an achievement to get round in one piece!
 
I’ve seen a few oil experts talking about the same subject and they were explaining that thinner oil actually takes heat out of an engine more efficiently than thicker oil

I run a 280hp DC2 with close gearing in 20min races using 5w40 Ester synthetic oil up to 130degrees without any issues, I’ve only fitted an oil cooler recently and temps don’t go above 110... 120 should not give any problems with good oil... up at 130 you would want an external cooler but you know that anyway


It’s a very unforgiving circuit which is why we took it easy enough out there but even at a medium pace there is still a risk of a bad accident... I suppose if it wasn’t dangerous it wouldn’t seem like as much of an achievement to get round in one piece!

That's interesting to hear, as you would automatically think the reverse of that. Do you still have a B18 with 280hp?! Or are you K swapped?

Small update, changed the oil and filter out for the 10W50. Went for a drive and still experiencing the same issues. Within 10 minutes of VTEC at various speeds/rpm I was up at 125degrees, without even driving flat out like on a circuit
So it appears to have achieved no difference .

Oh well, can but try things. I was always going to change the oil after the ring anyway.

Yourself and @xxxencorexxx stated that you use ester oils. What exact brand oil do you run?

I will still be investing in an oil cooler in the near future anyhow .
 
Normal road driving you should’nt see much more than 110degrees so either your gauge is reading high or your OEM heat exchanger/radiator isn’t working too well

An external oil cooler will take a bit of strain away from the coolant system too

I’m using a forged k24 bottom end with a standard k20a2 head in the car now

I use Millers CFS 5w40
 
Normal road driving you should’nt see much more than 110degrees so either your gauge is reading high or your OEM heat exchanger/radiator isn’t working too well

An external oil cooler will take a bit of strain away from the coolant system too

I’m using a forged k24 bottom end with a standard k20a2 head in the car now

I use Millers CFS 5w40

No sorry, I should have said 125degrees was my oil temperature. My coolant temp has never gone past 100. Steady at about 95 usually .

Oh okay, not really too comparable with b series Vs a frank haha

So is that oil fully synthetic? The Fuchs I use is ester fully synthetic so not sure if there is any difference between the two?
 
I know you meant oil temps but the OEM oil cooler/heat exchanger is cooled by your coolant so the less efficient the coolant radiator the less effective it is at cooling the oil and it doesn’t really do enough cooling for track work

I ran a B16b ek9 with a close gear set so it didn’t drop below about 7500rpm on track and it would see 135degrees on a normal track day and around 110 on the road

Yes the Millers CFS is their nano tech Motorsport oil and is Ester synthetic. The Fuchs pro race is good oil too
 
As spek9 and i mentioned I would go over your oem cooler system and check it all over including radiator etc.
I too am using Millers CFS 5w40
 
I know you meant oil temps but the OEM oil cooler/heat exchanger is cooled by your coolant so the less efficient the coolant radiator the less effective it is at cooling the oil and it doesn’t really do enough cooling for track work

I ran a B16b ek9 with a close gear set so it didn’t drop below about 7500rpm on track and it would see 135degrees on a normal track day and around 110 on the road

Yes the Millers CFS is their nano tech Motorsport oil and is Ester synthetic. The Fuchs pro race is good oil too

Ah sorry, yeah I'm with you now. Forgot the type R engines have the OEM oil coolers.
Is that just in general that the coolers aren't up to the job for track use? Or maybe there is something at fault with my individual car?

So potentially if I got an aftermarket radiator I may see cooler oil temps in return as it's more efficient?

As spek9 and i mentioned I would go over your oem cooler system and check it all over including radiator etc.
I too am using Millers CFS 5w40

Well there's nothing "wrong" with the cooling system as in it all operates correctly. New thermostat a year ago along with a coolant change.
Only thing the cars got is Mishimoto radiator hoses that are aftermarket .
 
Ah sorry, yeah I'm with you now. Forgot the type R engines have the OEM oil coolers.
Is that just in general that the coolers aren't up to the job for track use? Or maybe there is something at fault with my individual car?

So potentially if I got an aftermarket radiator I may see cooler oil temps in return as it's more efficient?



Well there's nothing "wrong" with the cooling system as in it all operates correctly. New thermostat a year ago along with a coolant change.
Only thing the cars got is Mishimoto radiator hoses that are aftermarket .
Well if nothing is wrong, there is some issue somewhere obviously.
 
Ah sorry, yeah I'm with you now. Forgot the type R engines have the OEM oil coolers.
Is that just in general that the coolers aren't up to the job for track use? Or maybe there is something at fault with my individual car?

So potentially if I got an aftermarket radiator I may see cooler oil temps in return as it's more efficient?



Well there's nothing "wrong" with the cooling system as in it all operates correctly. New thermostat a year ago along with a coolant change.
Only thing the cars got is Mishimoto radiator hoses that are aftermarket .


Maybe your OEM radiator has a load of damaged fins? Or is there an air con rad in front of the radiator?

A good aftermarket radiator will help keep oil temps down up to a certain point but for track work like you say it’s not really up to the job for more than a couple of laps and that’s when you want to fit an external oil cooler
 
@SPek9 the fact that Simon is hitting 125 within 10minutes on the street should lead us to believe something needs to be checked over. Cooling system, radiator system, gauge etc. I would worry about street first before thinking about track cooling and external coolers.
 
Maybe your OEM radiator has a load of damaged fins? Or is there an air con rad in front of the radiator?

A good aftermarket radiator will help keep oil temps down up to a certain point but for track work like you say it’s not really up to the job for more than a couple of laps and that’s when you want to fit an external oil cooler

Yeah possibly, I couldn't say for certain that there aren't too many damaged fins. I would guess not though.
There is however an A/C condensor in front of it still .

@SPek9 the fact that Simon is hitting 125 within 10minutes on the street should lead us to believe something needs to be checked over. Cooling system, radiator system, gauge etc. I would worry about street first before thinking about track cooling and external coolers.

Just to reiterate, I hit 125 after 10 minutes of driving the car 85% flat out.
When I'm on the motorway driving at 70mph comtinously my oil temp is a steady 95. If that makes any difference?
 
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