Half Fast’s GTI

[Half fast]

I took some video during a DE yesterday at Autobahn Country Club. I posted it on YouTube to make it easier to send to some friends, but figured it might be of interest to some people here that aren't my friends. The video is of an entire session (that got cut short) because it requires too much thought on my part to edit the video down. If you just want to skip to the best lap of the session, it starts at 11:15ish. I've done quite a few of these but this was my first time at this track. It's a pretty cool place; only complaint is that a handful of the apexes have dips in them that my car didn't like at all.

My car is also having some cooling issues that I need to sort out. So, if anybody has any ideas on that front, I'd love to hear them. The oil temps stay below 270 but I've had the coolant spike when the ambient temperature is >85. I've changed my mind about 100 times on whether to get the CSF radiator (expensive, unclear it if works), put in a Golf R aux radiator (perhaps slightly less expensive, unsure if possible without extensive fabrication, more difficult), or put vents in the hood (cheap, looks stupid on a car I drive in the street, results in holes above the shifter/battery area where water can get in). Other cooling issues I have are related to the brakes. The 986 calipers worked great on this car when everything else was stock but I'm going to have to switch to Macan calipers (already had the 986 calipers when I got the car so that's why I opted for them) to get the larger rotor/cooling capacity.

 

[jay745]

Autobahn is a fun track, I like to go on Mondays where they run full track. Gotta get back there sometime soon.

 

[Half fast]

I didn't even know the place existed until a month or so ago. I was registering for a different event and saw it scrolling down the list. I definitely want to get back there.

 

[R Golf]

Nice driving. Busy track. I love the tons of runoff. It's nice when tracks enable you to push that little bit harder. Especailly when you need to drive your car home after the event.

What issues are you having with the brakes? Looking at your mods I have to assume you are using really good hi-temp fluid and track focused pads. High 80's ambient shouldn't be an issue on track with decent pads, and good fluid. I have stock rotors and calipers with zero issues even in the 90's on tough tracks using Ferodo DS2500 and Mutul RBF 600. Could it be that you are overbraking?

Only help I can give on water temps is that my nephew's track focused BMW has same issues as you. Oil is totally fine (has oil coolers), but water gets too hot when pushing in very hot weather (he has aftermarket radiator, but not tons of space for airflow). He just installed two large sets of louvers on his BMW track focused car. The results showed much less improvement than all the marketing hype and temp graphs on mfg's websites. Was not the fix he was looking for.

 

[Half fast]

What issues are you having with the brakes? Looking at your mods I have to assume you are using really good hi-temp fluid and track focused pads. High 80's ambient shouldn't be an issue on track with decent pads, and good fluid. I have stock rotors and calipers with zero issues even in the 90's on tough tracks using Ferodo DS2500 and Mutul RBF 600. Could it be that you are overbraking?

I don't have issues with the brakes overheating so much as I'm eating the inside pads up quite a bit faster which says to me that the inside pads are getting too hot. I saw this issue at Mid Ohio where the car gets up to 130+ on the back straight with the IS38 when I was about 10mph slower before. I'm running the same Motul fluid with Pagid Orange pads. They've worked great but they just don't last as long as they did when the car was slower which is probably to be expected. So, it's an issue with longevity rather than performance. I could also swap the pads in the caliper to help, but I hate working on the car at the track, especially when it's hot (both outside, and the car itself).

That being said, I am also willing to admit I probably use a bit too much of the brakes as well.

 

[Mini7]

Oil and water temps are an issue when pushing hard on track with Summer ambients.

My CSF Radiator install. https://golfmk7.com/forums/index.php?threads/2017-gti-pp-at-vir.351754/post-7444979

With the Rona, my track events were cancelled and I haven’t been able to test the mod under track conditions. Quality is decent. You will see my challenges to get this to fit with an upgraded IC. It’s not quite plug and play, but it does fit. No issues or leaks on mine after a few months. No chafing of hoses either.

Last Wednesday I hooked up my OBD11 and monitored coolant temps. Under highway condition, coolant ran around 201-203F at cruise. Going up through the mountains in 4-gear dropped temps to 182-185F which surprised me as I thought going up the steep road with plenty of throttle would increase temps. Thinking about it, it may be a function of increased water pump speed and the higher coolant capacity of the triple pass CSF radiator dropping temps. Promising but the true test will be to get back to the track.

 

[Mini7]

Just read that you have upgraded to an IS38. On track coolant capacity is not going to have the capacity to keep temps in check. You will likely need an oil cooler. I went the CSF route to delay the installation of an oil cooler Or avoid it if I can. I generally run in early spring and late fall, so ambient temps are low.

 

[Half fast]

I stumbled on your CSF install yesterday while poking around. I've circled back to that being my next move.

The oil temps have stayed low enough, so I'm hoping that if I can get the coolant temps down, I can also avoid the oil cooler. The stock oil cooler is doing its job, even if the rest of the cooling system can't keep up. The VWR oil cooler doesn't seem to be a great solution and I don't want to pay $500 for that kit just to have to replace almost every part in it. Also, I want to keep the stock cooler because I live up north where it gets cold enough to need that to get things warmed up.

Only reason I upgraded to the IS38 is the wastegate on the IS20 failed and I figured, for similar money, I might as well have more power. Should have known better than to think it'd be that simple. I don't regret it though; car is a ton of fun.

 

[Half fast]

Put the CSF radiator in and I’m at Mid Ohio this weekend. First run it was 82 degrees outside (according to the car) and I got the water temp up to 237 in a few laps. Going to end up adding an aux radiator or vents in the hood.

I don’t have a good basis of comparison regarding temps before the install because I only noticed the issue after seeing the dash gauge spike. Used my Cobb unit to monitor temps this time around. But the stock gauge is moving just like it did before.

 

[Mini7]

Stock coolant gauge is a placebo.

Did you log oil temps with your Cobb? I’m more interested in that. My OBD11 does not log oil temps on the live gauge for some reason. Because that will determine whether I need to go to a 50-weight oil or add the oil cooler. A tuned IS38 will generate more heat than my tuned IS20. An IS 38 is on my list though. Running on track will test the system.

Do you need the R- bumper to do the Aux Radiator?

 

[Half fast]

I’ll have both the oil and coolant temps on the Accessport tomorrow. I read that the oil temp gauge in the dash was pretty accurate but I might as well get both temps from the same spot. Only time temps cracked 260 was after the coolant temp would spike. I can’t be sure, but it seems like the oil temps only rise when the water cooling system is maxed out.

I’m sure the best way to put an aux radiator in would be to get an R bumper. But, I don’t have fogs so I think I’ll try to see how it works by just pulling the fake grille out first.

 

[Mini7]

I was surprised that OBD11 cannot pull live oil temp data when it’s available on the dash. 260 isn’t terrible considering your mods and if you’re pushing hard on track. I’ve gotten to 270-275 on stock power and stock cooling system on a 85F day.

Have fun tomorrow. Keep it shiny side up! Keep posting.

 

[Half fast]

Yeah, I’ve been pleasantly surprised that the oil temps have been staying low. It looks like far more people have an issue with the oil temps than coolant temps.

We also have a stock power R here that I am going to try to get some data from. Oil temps in that got to the mid 260s so I’m curious where the coolant is.

 

[Half fast]

So here were the temps for the day:

Ambient Temp On Dash	Max Coolant Temp	Max Oil Temp
72	230	264
80	234	264
83	237	264
82	234	262

All of the temps are the max reported temps from the Accessport. FWIW, the oil temps on my Accessport and on the dash were always within a few degrees of each other. I think the reading on the dash is just “dampened”; there were times where it even read higher because the temps on the Accessport had dropped and the dash hadn’t reacted yet.

I ran the heater at full blast for most of the 4th session which seems to have helped and leads me to believe that an aux radiator would solve my problems. Last time the bumper was off, I noticed there are studs on the body inside the fender that appear to be where the bracket for the aux radiator mounts which means it should be as easy as getting the parts. Alternatively, I could only run events where the temps are in the 70s.

 

[Mini7]

I’d be curious how much the Aux cooler drops the coolant temps and then the oil Temps For you. I’m guessing about 10-F and no need to run the heater.

Good to see the CSF radiator tested on track. I would expect to see 10 to 15-degree lower oil temps on my Stg 1 IS20 vs. your tuned IS38.