The G37S is a great track car
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No, they sell a package where you buy an LSD from them (I got the Wavetrac), and they install it into a rear diff housing for you. So when you take receipt of it, you swap out your rear diff, and send them back your core. It's convenient for people like me who don't want to worry about setting lash on the ring and pinion, or want to press in the carrier bearings. But the package comes with diff bushings, finned diff cover, and fluid. Of course, all in addition to the actual LSD and R&P ratio you choose.
And now the bad: I did the first two sessions on just over 1/2 a tank of gas so I figured I would be ok to do the 3rd. About 15min into that session I got a fuel cutoff going down the kettle bottoms into Canada corner. The next lap it happened in the same spot and also on the main straight. The gas light came on and it was right on E so I left early to gas up. When I got to the gas station I was almost up to 1/4 tank so if you are low, fill it up. Keep in mind I got 65 min of high speed driving out of one tank so not so bad and an easy thing to keep an eye on.
I have coolant stain all over the front of the engine too, so seeing the same there even tho the temp "gauge" (indicator) is rock solid and doesn't move from the middle.
I will be visiting the Infiniti dealer and politely requesting a new one.
On the last session the ABS failed and I flat spotted the RF tire braking into turn 8. I initially thought it was the car behind me squealing the tires as the brakes felt exactly the same. In the split second it took for me to see the smoke and lifting off the brake the tire was already flat spotted. The car is throwing a code for a RR ABS sensor.
I'd be really interested to see how you go with a set of decent 2 piece rotors in the front. I was hammering the brakes at COTA in 104 degree heat and despite a long pedal had absolutely no trouble. In contrast, my RE-71R's went off at about the 15 minute mark and were useless. I was 5s per lap off my own pace slipping and sliding everywhere, but no brake issues except the front right seeped a tiny bit and the fluid looked pretty old when I bled it, but nothing like discoloured paint. I have also purchased some titanium backing plates to help keep the pedal nice and firm for the next outing.
I would really like to figure out how to get these brake ducts installed that I bought. I'm thinking I might need to buy one of the small windscreen washer reservoirs that STILLEN specs with their intake kit so that I can make space on the passenger side for the ducting, but even up front for the inlets there isn't much space and I haven't figured out the rotor end mounting either.
Last edited by Splitter; Oct 6, 2016 at 02:03 PM.
Oh, and more autocross fun from last weekend 
This was my most fun video from the day, just being stupid and over driving to get a feel for the car.
Makes me really disappointed that I didn't get more time in the car with this setup before COTA, I went from being about 2s slower than the M3's to being ahead (just) of them with the new sway bar and tyres. Autocross gives you the chance to figure the car out in a danger free environment, you can guarantee I didn't once push anywhere near this hard in Austin, but I will next time.

This was my most fun video from the day, just being stupid and over driving to get a feel for the car.
Makes me really disappointed that I didn't get more time in the car with this setup before COTA, I went from being about 2s slower than the M3's to being ahead (just) of them with the new sway bar and tyres. Autocross gives you the chance to figure the car out in a danger free environment, you can guarantee I didn't once push anywhere near this hard in Austin, but I will next time.
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My responses are in bold
When I was at COTA, I was going through about a 1/4 tank per session. I was driving to the gas station after each heat, except for my last and I got really bad fuel starve on the very long triple apex right hander and all down the pit straight, had to call the session early. I would advise - as is readily available from the 370z guys - to top-off after each run. It was a brain fart by me, but ruined that session for me, and track days aren't cheap that you want to lose runs.
I think I can easily get two 25min sessions at Road America out of a tank, but if you get below 1/2 tank it sure goes quickly and thinks it is empty almost 1/4 tank early.
I have the Z1 power steering cooler with Redline fluid and still leaked fluid at COTA and a recent autocross. Nothing serious, but I run at "Hot Low" level and it still seeps out.
Wow, that's crazy. Guess I won't waste time trying to fit a power steering cooler. I was just surprised how much less fluid was leaking at Road America compared to Shawano, which is a lot more technical. Someone here was trying to convince me that it was due to higher rpms and not how much you were actually turning the steering wheel. Turns out that theory is completely wrong.
I have coolant stain all over the front of the engine too, so seeing the same there even tho the temp "gauge" (indicator) is rock solid and doesn't move from the middle.
Bummer, I wonder if water wetter would make much difference or if a bigger radiator is necessary.
Mine did the same! This weekend I popped the hood for autocross scrutineering and it's gone. One of the pins is snapped and stuck in the top of the engine but the rest is gone. Also unknown where it's been left lying around, but it's not in the engine bay any more.
I will be visiting the Infiniti dealer and politely requesting a new one.
Oh good, so it's not just me.
Wow, that's pretty bad luck and ridiculously expensive for an ABS sensor!
Turns out it was $237 for the pair, not each. So slightly better. We sent it in for a warranty claim, but I doubt it will get covered.
I'd be really interested to see how you go with a set of decent 2 piece rotors in the front. I was hammering the brakes at COTA in 104 degree heat and despite a long pedal had absolutely no trouble. In contrast, my RE-71R's went off at about the 15 minute mark and were useless. I was 5s per lap off my own pace slipping and sliding everywhere, but no brake issues except the front right seeped a tiny bit and the fluid looked pretty old when I bled it, but nothing like discoloured paint. I have also purchased some titanium backing plates to help keep the pedal nice and firm for the next outing.
My brakes were pretty solid too with the pads and fluid I use. They did leak a bit from the bleeders though. Be careful with the titanium backing plates. I used those once and they do save your fluid a bit, but put a lot of extra heat into the pads.
That's strange you had issues with the tires. I run the same on my tank of a sedan and they are solid and wear really evenly.
I would really like to figure out how to get these brake ducts installed that I bought. I'm thinking I might need to buy one of the small windscreen washer reservoirs that STILLEN specs with their intake kit so that I can make space on the passenger side for the ducting, but even up front for the inlets there isn't much space and I haven't figured out the rotor end mounting either.
What brake ducts did you get?
I think I can easily get two 25min sessions at Road America out of a tank, but if you get below 1/2 tank it sure goes quickly and thinks it is empty almost 1/4 tank early.
I have the Z1 power steering cooler with Redline fluid and still leaked fluid at COTA and a recent autocross. Nothing serious, but I run at "Hot Low" level and it still seeps out.
Wow, that's crazy. Guess I won't waste time trying to fit a power steering cooler. I was just surprised how much less fluid was leaking at Road America compared to Shawano, which is a lot more technical. Someone here was trying to convince me that it was due to higher rpms and not how much you were actually turning the steering wheel. Turns out that theory is completely wrong.
I have coolant stain all over the front of the engine too, so seeing the same there even tho the temp "gauge" (indicator) is rock solid and doesn't move from the middle.
Bummer, I wonder if water wetter would make much difference or if a bigger radiator is necessary.
Mine did the same! This weekend I popped the hood for autocross scrutineering and it's gone. One of the pins is snapped and stuck in the top of the engine but the rest is gone. Also unknown where it's been left lying around, but it's not in the engine bay any more.
I will be visiting the Infiniti dealer and politely requesting a new one.
Oh good, so it's not just me.
Wow, that's pretty bad luck and ridiculously expensive for an ABS sensor!
Turns out it was $237 for the pair, not each. So slightly better. We sent it in for a warranty claim, but I doubt it will get covered.
I'd be really interested to see how you go with a set of decent 2 piece rotors in the front. I was hammering the brakes at COTA in 104 degree heat and despite a long pedal had absolutely no trouble. In contrast, my RE-71R's went off at about the 15 minute mark and were useless. I was 5s per lap off my own pace slipping and sliding everywhere, but no brake issues except the front right seeped a tiny bit and the fluid looked pretty old when I bled it, but nothing like discoloured paint. I have also purchased some titanium backing plates to help keep the pedal nice and firm for the next outing.
My brakes were pretty solid too with the pads and fluid I use. They did leak a bit from the bleeders though. Be careful with the titanium backing plates. I used those once and they do save your fluid a bit, but put a lot of extra heat into the pads.
That's strange you had issues with the tires. I run the same on my tank of a sedan and they are solid and wear really evenly.
I would really like to figure out how to get these brake ducts installed that I bought. I'm thinking I might need to buy one of the small windscreen washer reservoirs that STILLEN specs with their intake kit so that I can make space on the passenger side for the ducting, but even up front for the inlets there isn't much space and I haven't figured out the rotor end mounting either.
What brake ducts did you get?
Last edited by 4DRZ; Oct 6, 2016 at 11:05 PM.
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Oh, and more autocross fun from last weekend 
Dadson Racing - Houston SCCA Autocross - October 2 2016 - YouTube
This was my most fun video from the day, just being stupid and over driving to get a feel for the car.
Makes me really disappointed that I didn't get more time in the car with this setup before COTA, I went from being about 2s slower than the M3's to being ahead (just) of them with the new sway bar and tyres. Autocross gives you the chance to figure the car out in a danger free environment, you can guarantee I didn't once push anywhere near this hard in Austin, but I will next time.

Dadson Racing - Houston SCCA Autocross - October 2 2016 - YouTube
This was my most fun video from the day, just being stupid and over driving to get a feel for the car.
Makes me really disappointed that I didn't get more time in the car with this setup before COTA, I went from being about 2s slower than the M3's to being ahead (just) of them with the new sway bar and tyres. Autocross gives you the chance to figure the car out in a danger free environment, you can guarantee I didn't once push anywhere near this hard in Austin, but I will next time.
El-stocko
I believe it's the IPL/Nismo muffler and the rest is the same as an S exhaust?
From here:
2015 Infiniti Q60 Coupe Press Kit - Infiniti Online Newsroom
Is this line:
"Infiniti Q60S Coupe Limited models include a stainless steel sport muffler."
I don't know if it's full NISMO cat back, I haven't checked, but this is absolutely what the muffler looks like, 5" tips and all

I believe it's the IPL/Nismo muffler and the rest is the same as an S exhaust?
From here:
2015 Infiniti Q60 Coupe Press Kit - Infiniti Online Newsroom
Is this line:
"Infiniti Q60S Coupe Limited models include a stainless steel sport muffler."
I don't know if it's full NISMO cat back, I haven't checked, but this is absolutely what the muffler looks like, 5" tips and all

Don't get me wrong, the power steering cooler works, just doesn't elimiate seeping. I had over a cup of powersteering fluid in my wheel well at Texas World Speedway and just a little seeping at COTA.
Most of the 370z guys go to a massive oversize radiator for track/boosted setups. Mishimoto does one that is about twice the capacity I think, it's pretty substantial upgrade.
I didn't know about that with the brake pad heat shields, but I guess it makes sense. The Carbotech pads are supposed to be pretty good, so we'll see what happens.
I just bought brake duct lines, inlets and some 2.5" exhaust to try and do a DIY fab, I didn't buy a kit. However, my windscreen washer bottle is bigger than any pictures I've seen online. I couldn't route the oil cooler as per any instructions I found online as there just isn't space, which means it's impossible to fit the brake ducting through. Hence why I'm thinking about getting a stillen small washer bottle. That or just not bother, I haven't decided yet, but it's $150+ of stuff just sitting in the garage
Most of the 370z guys go to a massive oversize radiator for track/boosted setups. Mishimoto does one that is about twice the capacity I think, it's pretty substantial upgrade.
I didn't know about that with the brake pad heat shields, but I guess it makes sense. The Carbotech pads are supposed to be pretty good, so we'll see what happens.
I just bought brake duct lines, inlets and some 2.5" exhaust to try and do a DIY fab, I didn't buy a kit. However, my windscreen washer bottle is bigger than any pictures I've seen online. I couldn't route the oil cooler as per any instructions I found online as there just isn't space, which means it's impossible to fit the brake ducting through. Hence why I'm thinking about getting a stillen small washer bottle. That or just not bother, I haven't decided yet, but it's $150+ of stuff just sitting in the garage
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I didn't know about that with the brake pad heat shields, but I guess it makes sense. The Carbotech pads are supposed to be pretty good, so we'll see what happens.
I just bought brake duct lines, inlets and some 2.5" exhaust to try and do a DIY fab, I didn't buy a kit. However, my windscreen washer bottle is bigger than any pictures I've seen online. I couldn't route the oil cooler as per any instructions I found online as there just isn't space, which means it's impossible to fit the brake ducting through. Hence why I'm thinking about getting a stillen small washer bottle. That or just not bother, I haven't decided yet, but it's $150+ of stuff just sitting in the garage
I just bought brake duct lines, inlets and some 2.5" exhaust to try and do a DIY fab, I didn't buy a kit. However, my windscreen washer bottle is bigger than any pictures I've seen online. I couldn't route the oil cooler as per any instructions I found online as there just isn't space, which means it's impossible to fit the brake ducting through. Hence why I'm thinking about getting a stillen small washer bottle. That or just not bother, I haven't decided yet, but it's $150+ of stuff just sitting in the garage

I know what you mean about installing an oil cooler. Stillen's instructions were awful and their "tech support" was even worse. Once I decided to ignore both of those and use logic, it went just fine.
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Just wondering about the slight coolant leak out of the overflow tank. I am assuming this is caused by the coolant getting too hot. Oddly enough the temperature gauge never moved. I am sure I could benefit from some water wetter or similar additive. Maybe a bigger radiator down the road?
I am wondering if coolant goes bad from too much heat like brake fluid and I need to replace it or if it is fine and just boils over from too much heat.
I am wondering if coolant goes bad from too much heat like brake fluid and I need to replace it or if it is fine and just boils over from too much heat.
Just wondering about the slight coolant leak out of the overflow tank. I am assuming this is caused by the coolant getting too hot. Oddly enough the temperature gauge never moved. I am sure I could benefit from some water wetter or similar additive. Maybe a bigger radiator down the road?
I am wondering if coolant goes bad from too much heat like brake fluid and I need to replace it or if it is fine and just boils over from too much heat.
I am wondering if coolant goes bad from too much heat like brake fluid and I need to replace it or if it is fine and just boils over from too much heat.
This is done to prevent people freaking out and taking the car back for warranty work as the coolant temperature fluctuates during normal use.
Use an OBD2 scanner & app to data log your coolant temps. My testing has shown if the car is moving quickly, coolest temps are =< 100C (212 F) when at the track, BUT oil temps are much higher, unless you have an oil cooler.
As far as I am aware, coolant is not damaged by higher temps.
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The temp gauge is "buffered" and movement is not linear. From my testing the gauge does not move from the middle position when coolant temp is between 82 and 102 deg C (180-215)
This is done to prevent people freaking out and taking the car back for warranty work as the coolant temperature fluctuates during normal use.
Use an OBD2 scanner & app to data log your coolant temps. My testing has shown if the car is moving quickly, coolest temps are =< 100C (212 F) when at the track, BUT oil temps are much higher, unless you have an oil cooler.
As far as I am aware, coolant is not damaged by higher temps.
This is done to prevent people freaking out and taking the car back for warranty work as the coolant temperature fluctuates during normal use.
Use an OBD2 scanner & app to data log your coolant temps. My testing has shown if the car is moving quickly, coolest temps are =< 100C (212 F) when at the track, BUT oil temps are much higher, unless you have an oil cooler.
As far as I am aware, coolant is not damaged by higher temps.
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Ok so I think my original thread title should have referred to short tracks or autocrosses. I think with a long track like Road America and long sessions the car can still be surprisingly good, it just needs a few more things to cope with the heat.
Definitely higher temp fluid in the rear diff and power steering. A bigger capacity rear diff cooler with cooling fins and an insulated clutch cable are not bad ideas either.
I just ordered an insulated clutch cable so I will do that when I flush the clutch fluid.
I also got a CE light related to the right bank Z1 high flow cat. Took it off to make sure nothing melted so it looks like I will need a tune to fix that.
Is anyone running track days ok with just high temp fluid in the clutch and rear diff without a different rear diff cover or clutch cable? I think you would need the rear diff cover before the clutch cable.
Definitely higher temp fluid in the rear diff and power steering. A bigger capacity rear diff cooler with cooling fins and an insulated clutch cable are not bad ideas either.
I just ordered an insulated clutch cable so I will do that when I flush the clutch fluid.
I also got a CE light related to the right bank Z1 high flow cat. Took it off to make sure nothing melted so it looks like I will need a tune to fix that.
Is anyone running track days ok with just high temp fluid in the clutch and rear diff without a different rear diff cover or clutch cable? I think you would need the rear diff cover before the clutch cable.
I have toyed with the idea of the Z1 diff cover, but decided that if I was going to go to the effort then I would do the mounts as well, and while it was out of the car I would look at a proper LSD, cause the standard one is pretty abysmal. At the better part of $2,000 by that time I have decided not to touch it.
I do have redline fluid in the diff tho to try and help with the heat somewhat.
The clutch on these is a weak point and most swap the slave cylinder out entirely for the aftermarket options, so I would consider the clutch sleeve or an entire replacement before rear diff changes.
I have decided that the best option for me is shorter sessions. It's cultural, but when I started racing in Aus, the longest session that any club would let you do was 10-15 minutes as that's about all that most standard cars can handle before things go bad. It amazes me that clubs over here all run 20 minutes sessions due to the punishment a car goes through in that time.
For me, 15 minutes is more than enough to get a fix and keep the car under control and so far has worked well enough with heat management. It's not ideal, but then this car is all about compromise and if I wanted a real race car I would have bought a real race car and not a luxury cruiser.
I do have redline fluid in the diff tho to try and help with the heat somewhat.
The clutch on these is a weak point and most swap the slave cylinder out entirely for the aftermarket options, so I would consider the clutch sleeve or an entire replacement before rear diff changes.
I have decided that the best option for me is shorter sessions. It's cultural, but when I started racing in Aus, the longest session that any club would let you do was 10-15 minutes as that's about all that most standard cars can handle before things go bad. It amazes me that clubs over here all run 20 minutes sessions due to the punishment a car goes through in that time.
For me, 15 minutes is more than enough to get a fix and keep the car under control and so far has worked well enough with heat management. It's not ideal, but then this car is all about compromise and if I wanted a real race car I would have bought a real race car and not a luxury cruiser.
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I agree completely on the longer sessions. Most track days here do about 15min. sessions on the short tracks and I always though it was 20min. at Road America, but this was the first track day they ever hosted themselves so maybe that is what they were 25 min. sessions. That being said, the car held up really well until the very end. Easy enough to pull of a bit early.
So have you had any issues with heat in your rear diff with the redline fluid?
So have you had any issues with heat in your rear diff with the redline fluid?






