I did a thing.. '19 ZL1 1LE Build

Matts96HB

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I bled the brakes with a fresh bottle of Castrol SRF last night. I put 7 full track days on this fluid without touching it and it looked basically brand new. I'll have to take pics sometime but basically I'm using a Motive pressure bleeder with a small pump hooked up to it in lieu of the manual pump. I fill the tank with fluid, pressure up the system to ~25 psi, and crack the bleeder valve. It pushes fluid through incredibly fast, and I am able to do a complete flush on the system in less than 30 minutes. Not bad at all.
 

|Chaz|

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This car is so sweet. Good choice, the wrap makes the car. Way more interesting than the GTR. Its hard to believe how well they go around a track now compared to how they did 20 years ago.
 

TurboMirage

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the old ones go pretty good to......... if you replace the entire suspension and braking system with modern bolt-on components (they make kits, we have a few scca cars with them)
 

B16

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the old ones go pretty good to......... if you replace the entire suspension and braking system with modern bolt-on components (they make kits, we have a few scca cars with them)
haha, read the first part and was like, hold on a sec... then you captured it quite well. lol.
 

Matts96HB

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This car is so sweet. Good choice, the wrap makes the car. Way more interesting than the GTR. Its hard to believe how well they go around a track now compared to how they did 20 years ago.
Thanks man! I always tell people both this car and the GTR are fantastic in their own ways. The GTR really was an amazing all around performer. This car is miles ahead of it in terms of being a competent track car, especially stock-vs-stock.
the old ones go pretty good to......... if you replace the entire suspension and braking system with modern bolt-on components (they make kits, we have a few scca cars with them)
I'll never forget the first f-body I saw flying around the track. I thought to myself, "where's all the body roll!?" yeah, well I caught up with the guy in the pits and it was far from stock. lol
haha, read the first part and was like, hold on a sec... then you captured it quite well. lol.
lol thought the same thing
 

Matts96HB

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I ran my slicks for the first time at MSR Cresson yesterday. I was able to shave a little over a second off of my PB (1:19.78 vs 1:21.15) but didn't get too many laps in because I was busy instructing and had a leaky valve stem during the first two sessions. I came in with 15 psi in the LR after the second session and realized that was why I had been sliding all over the damn place.. lol
 

get_nick

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The GTR really was an amazing all around performer. This car is miles ahead of it in terms of being a competent track car, especially stock-vs-stock.
How? WHY?!?!

There's no way Nissan can be ok with this. Did they just forget about the GTR's racing roots? Were they trying to accommodate the rich kids and mid-life crisis dads and just product a shitty car? I'm scratching my head here.
 

Matts96HB

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How? WHY?!?!

There's no way Nissan can be ok with this. Did they just forget about the GTR's racing roots? Were they trying to accommodate the rich kids and mid-life crisis dads and just product a shitty car? I'm scratching my head here.
If we're talking stock vs. stock..
  1. The GTR has shitty brakes. The rotors crack, pads fade, fluid boils..
  2. It needs a transmission cooler to keep the DCT cool if you plan on running more than 2-3 hot laps
  3. It needs brake cooling if you hope to keep the brakes working properly
  4. The fluids are stupid expensive ($50 oil change, $500-600+ for trans fluid if you DIY)
  5. The stock tires are pathetic. Swap those and it's an easy 2s per lap on most tracks
In contrast..
  1. I ran the stock pads to the end of their life on the Camaro with 0 fade, no cracked rotors (I changed fluid because I'm paranoid)
  2. It needs nothing to stay cool
  3. It comes with sticky 100 TW tires from factory
  4. The fluids are cheap ($75 oil change, $40 for diff, maybe $100 for MT but it never gets hot so no need to change it regularly)
  5. I can hot lap the car for a whole session and nothing changes - there is no need to short shift, keep my eye on gauges, etc.. I just drive
The GTR isn't a shitty car by any stretch of the imagination. It'd make a great daily driver, the build quality is great for the price point, can be made stupid fast for relatively low investment, and it is an incredibly reliable car. It tracks okay but is not even in the same ball park when compared to the ZL1 1LE on the track.
 

get_nick

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If we're talking stock vs. stock..
  1. The GTR has shitty brakes. The rotors crack, pads fade, fluid boils..
  2. It needs a transmission cooler to keep the DCT cool if you plan on running more than 2-3 hot laps
  3. It needs brake cooling if you hope to keep the brakes working properly
  4. The fluids are stupid expensive ($50 oil change, $500-600+ for trans fluid if you DIY)
  5. The stock tires are pathetic. Swap those and it's an easy 2s per lap on most tracks
In contrast..
  1. I ran the stock pads to the end of their life on the Camaro with 0 fade, no cracked rotors (I changed fluid because I'm paranoid)
  2. It needs nothing to stay cool
  3. It comes with sticky 100 TW tires from factory
  4. The fluids are cheap ($75 oil change, $40 for diff, maybe $100 for MT but it never gets hot so no need to change it regularly)
  5. I can hot lap the car for a whole session and nothing changes - there is no need to short shift, keep my eye on gauges, etc.. I just drive
The GTR isn't a shitty car by any stretch of the imagination. It'd make a great daily driver, the build quality is great for the price point, can be made stupid fast for relatively low investment, and it is an incredibly reliable car. It tracks okay but is not even in the same ball park when compared to the ZL1 1LE on the track.
I guess I wasn't clear on my true question. Why/how did Nissan not make a good track car that was ready out of the box? Seems like they just didn't expect people to use it for racing. Which is counter to its roots.
 

Matts96HB

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I guess I wasn't clear on my true question. Why/how did Nissan not make a good track car that was ready out of the box? Seems like they just didn't expect people to use it for racing. Which is counter to its roots.
They knew their audience. How many car enthusiasts track their car more than 3-5 times per year? Not many. Fewer can afford a $65k+ car and still fewer will spend $65k+ on a car they know they're going to track. Most will go out and build a track car instead. They built a GT car that is capable of monstrous lap times while still appealing to the guy who wants to drive his car on the weekends without knocking his wife's spine out of alignment.. all at a price point that was untouchable at the time. I personally think they simply set out to accomplish a different goal than the original GTR.
 

Matts96HB

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Back to the Camaruh: one difference I noted is that TCS was more active with the slicks than it has been with the OEM tires. I usually run the car in PTM Race which has typically allowed for me to be able to steer the car with the throttle to a reasonable degree. It didn't feel that way with the slicks.

The OEM rear tires are 26.7" diameter, rear slicks are 680mm/26.77 inches
The OEM front tires are 26.2" diameter, front slicks are 680mm/26.77 inches

If my thinking is correct, this difference would slow the front wheel speed relative to the rear, and make the computer think there is some rear tire slip when there isn't. I don't know how significant it is, but I am thinking this caused TCS to kick in earlier.

On the straights, Pi toolbox shows a difference in wheel speed of ~2 mph with the slicks vs ~.75 mph with a set of worn GoodYear SuperCar 3Rs. Again, this seems like a really minor difference and might be nit-picking, but I am going to run the car with everything off from now on anyways.
Conti Slicks - Wheel Speed vs. TCS.PNG

Conti Slicks - TCS Active MSRC 1.7 CCW.PNG
 

Matts96HB

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Love the data logging
It is incredibly powerful for finding speed. The best part is that all the tools I've used are free if you get a car with the Performance Data Recording system.
I love this car, but I hate the wrap. Maybe I'm in the minority on this because I'm getting older. Just give me a nice paint color.
To each their own :) the good news is the wrap is keeping the paint nice and clean

I'm finally getting the Pilot Super Sports mounted to my 19" wheels on Friday. It'll be nice to have some tires that *should* last for a while on the street. I'm also going to be adding a cooler thermostat (170 deg) and a coolant expansion tank to the intercooler circuit. That should help reduce operating temps and keep the car from pulling timing during these 95 degree + track days. As of now, the temps stabilize at ~215F which is into the range where the car begins to pull timing. I just want to offset that by ~10-15 degrees, hopefully this will do the trick.
 

Matts96HB

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Another track day, another PB broken! Beat my previous PB by ~1 sec. Shown below is a 2:21.85, my AiM Solo2 said I did a 2:21.15 in the first session of the day but my SD card filled up for the PDR system :(. It was a hot day, and the car realllly showed it. I had 0 rear grip after the first two sessions. I tried adjusting the rear bar to the softest setting which didn't do much. Tried dropping ~4 psi out of the rear tires as well but they were still showing over inflated, so I suspect I've been running these WAY too high. Best I figure that out now before I head to COTA in a month.. :)
 

Matts96HB

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And, just as I had suspected, tire pressures were too high. I don't have TPMS in my track wheels (that's getting fixed shortly), so it is difficult to know what the on-track pressures were; however, after a cool down lap and some farting around in the pits, my pressures were ~34-36 psi hot all day. After asking for advice from those with far more experience than I, it seems I want to be in the 30-32 psi hot range. So that would explain the lack of rear grip and the crazy tire temperatures I was measuring this past weekend. Oh well, live and learn.
 
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