No overheating on 87 degree Sebring Track Day

[Chilly613]

That's an excellent video. In fact anyone into modding of any sort should smash that subscribe button for MotoIQ.

Love MotoIQ. Mike is a good dude and knows his shit.

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[MooMoo]

The thread is not derailed; suspension was brought up in the original post.

First, a disclaimer- I'm not an expert. Just a dude trying to be a dude pretending to be a dude who knows about suspension. But I do have anecdotal evidence of things I've done to my specific car, which is relevant. But I'd encourage folks to do their due diligence and feel free to report back if anything I say here is false. It will never be my intention to mislead, but hopefully my experience can help someone.

That out of the way- you can of course adjust the camber. Just not without buying stuff lol. There's no way to adjust the camber from the factory (you can pull the strut tower pins and adjust the top of the strut that way- but that's not an "official" adjustment methodology and you can only gain about .5 degree, likely less).

So you have two options- return to close to stock, or lean in with more aggressive camber. Or, a third and do nothing. MANY people have done the do nothing route (including myself). And many people have suffered no ill consequence. I did only because I actually take my car to autocross, which is a hell of a lot more demanding than street driving or even backroads. Although I'd recommend adjusting the camber if you frequently carve up backroads or canyons.

Anyway. Return to near stock camber settings- a variety of companies offer rear camber arms that are adjustable, look to spend another ~$300. Should be a pretty straightforward install but haven't done it myself. You will need an alignment rack to dial in the camber, I wouldn't recommend eyeballing it. The short explanation for why you only need rear camber adjustment because of the difference in suspension geometry between McPherson struts up front and multi-link out back. That's all according to the masters' plan in how the suspension is designed and what helps give it that wonderful lift-off oversteer even in stock form- but also what will make you want to rip your hair out when it pushes through cones during an autocross after you lower it (and do nothing else).

Adding more front camber- you have a couple choices there too. Most people go the route of adjustable lower ball joints. There's several options out there, but it seems like EVS is the way to go, as they all function pretty much exactly the same and the EVS are cheaper by a longshot. You can also elect to get camber plates that mount to the strut tower, sometimes referred to as "top hats". I used to think you pretty much had to have coilovers to go this route but that's apparently not the case and you can buy them independently. I have yet to do more research on this but even if you do the coil route, you still have to buy them separately in most cases I could see. Ohlins for example doesn't appear to offer their own camber plates, but Sakebomb does and I see a lot of folks use that combo. Personally, that's what I'd recommend... because one other component I'm not going to get too deep into is roll center adjusters. I've noticed more bump steer recently with the addition of a DSC controller that resulted in less damping (by default- I'm not going to get into DSC controller science for the time being as that IS off-topic...). Anyway, I have yet to account for the bump steer-inducing mechanics of the front lower control arms being at an "elevated" angle from what it was originally designed for, which leads to the toe "moving" when compressed; i.e., bump steer.

I'm probably not articulating that right, but it's annoying. And the only way to fix it on this platform (that I'm aware of) is with an elongated ball joint. Which I can't use because I need the adjustable ball joints for my front camber... which is why I don't think I'm done with my suspension tweaking, even though I like it. (Although I do go through tires at an alarming rate, and I'm still chasing that part down too... it might have something to do with -3.5 degrees of front camber. Just saying there's a chance.)

But the last thing I'll leave you with is I've never noticed a single more significant modification in handling than when adding more camber. It was a revelation. I never even really understood what "turn in" meant until I experienced it at my first autocross after adding the camber. I went from finishing in the middle of the pack, to being right back up there where I used to be with my Porsches.

But if you're not doing any type of competitive stuff you could skip all that and just bring the rear camber back to ~1-1.5 degrees and the car should behave very similarly to stock. Aside from the roll-center part but you could fix that with new ball joints.

from talking to a few people -3.5 camber is too much on this platform and why you are going through tires at an alarming rate, seems like -2.5 to -2.8 is the sweat spot.

To the OP I would definitely install some ball joints to get some more camber on the front if you going to keep tracking, its as mentioned by optronix one of the best modifications to not only get a bigger contact patch down but also to save your tire walls (even though you have to play with it or if you are day-lying the car too much camber can wear your tires quicker)

 

[Nikw91]

from talking to a few people -3.5 camber is too much on this platform and why you are going through tires at an alarming rate, seems like -2.5 to -2.8 is the sweat spot.

To the OP I would definitely install some ball joints to get some more camber on the front if you going to keep tracking, its as mentioned by optronix one of the best modifications to not only get a bigger contact patch down but also to save your tire walls (even though you have to play with it or if you are day-lying the car too much camber can wear your tires quicker)

I drive 30,000 miles a year plus track days every few months. So I don’t want to much camber that makes me blow through tires.

 

[optronix]

I drive 30,000 miles a year plus track days every few months. So I don’t want to much camber that makes me blow through tires.

If it helps at all, my tire issues stem almost exclusively from my autocross usage. I've been on my all seasons since November and they look brand new. ~7k miles on them alone.

 

[Ktrw]

Just wanted to touch on the 5W-30 point. Running 5W-30 won't help with oil temperatures at all, as it will likely run slightly hotter due to the higher viscosity. 5W-30 may still have a higher viscosity during track use than 0W-20, depending on how big the difference is. Many folks tend to run a thicker oil than the recommend spec when above 220F oil temp for the hydrodynamic wedge/bearing clearance relationship.

Oil pressure is an important characteristic that can be improved by running a thicker oil like 5W-30. From what I've seen, the K20C's seem to be good somewhere above 60psi on track, perhaps ideally 65psi and above so maybe take note of your oil pressure through various sections on track and use that as a metric as well. This will be highly dependent on ambient temp, your power level, fluid temps, etc., but you do want to maintain as consistent oil pressure as you can. Not to say below 60psi is suddenly bad, but often if the oil pressure dips below that it is typically when the oil is extremely hot or there is some sloshing or starvation due to cornering.

Since you have a nice cooling setup, maybe you can run 0W-20, maintain good oil pressure, and benefit from the lower temperatures.

 

[Nikw91]

Just wanted to touch on the 5W-30 point. Running 5W-30 won't help with oil temperatures at all, as it will likely run slightly hotter due to the higher viscosity. 5W-30 may still have a higher viscosity during track use than 0W-20, depending on how big the difference is. Many folks tend to run a thicker oil than the recommend spec when above 220F oil temp for the hydrodynamic wedge/bearing clearance relationship.

Oil pressure is an important characteristic that can be improved by running a thicker oil like 5W-30. From what I've seen, the K20C's seem to be good somewhere above 60psi on track, perhaps ideally 65psi and above so maybe take note of your oil pressure through various sections on track and use that as a metric as well. This will be highly dependent on ambient temp, your power level, fluid temps, etc., but you do want to maintain as consistent oil pressure as you can. Not to say below 60psi is suddenly bad, but often if the oil pressure dips below that it is typically when the oil is extremely hot or there is some sloshing or starvation due to cornering.

Since you have a nice cooling setup, maybe you can run 0W-20, maintain good oil pressure, and benefit from the lower temperatures.

Would running a let’s say, E30 blend, help lower temps at all? I know ethanol burns cooler. But also makes more power.

 

[Ktrw]

Would running a let’s say, E30 blend, help lower temps at all? I know ethanol burns cooler. But also makes more power.

Yeah running a higher ethanol blend could help lower temps. Ethanol being less energy dense requires more fuel which increases the in-cylinder cooling effect, and it has a higher latent heat of vaporization so it will pull more energy from the system to vaporize. The percent benefit may depend a bit on the how the tune is set up, obviously you could make more power since ethanol is more knock resistant, which would reduce the cooling benefit but not negate it since it is fairly significant. I remember Jester mentioning that he likes to run these cars rich on track where possible to help with temperatures anyway so he probably has a good strategy for that.

Do you have any fuel system upgrades other than the canflex to install? I'm not sure if you can get away with E30 on the stock fuel system on track, but maybe thats right at the limit depending on your car. IIRC, Drob has run some cars on E25/30 with the stock fuel system and turbo so maybe that is a safe limit depending on conditions. You wouldn't need injectors for the stock turbo, but you may need a HPFP as that is the primary restriction AFAIK. Regardless, the stock fuel system should be able to get in that E25-E30 range at which point the stock turbo will be maxed out.

 

[Jester04]

I would step up to 5w-30. That is what I run and 0 issues. I’m not a fan of the 0w-20 think it is too thin for track duty once some heat gets in there.

 

[Jester04]

On the ethanol front I would suggest running a e20 mix max to not tax the pump at the track. On the street I feel you can get away with e30 with a slightly leaner afr.

 

[Nikw91]

On the ethanol front I would suggest running a e20 mix max to not tax the pump at the track. On the street I feel you can get away with e30 with a slightly leaner afr.

Will E20 bring temps down slightly?

I’ll have to put the canflex on and hit you up for a retune soon. Just kinda hard when I only have MacBooks and no computers with Windows in the house.

 

[Jester04]

Will E20 bring temps down slightly?

I’ll have to put the canflex on and hit you up for a retune soon. Just kinda hard when I only have MacBooks and no computers with Windows in the house.

It will cool the cylinder better. As far as oil and coolant temps it will be negligible from my experience.

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