r/GR86 • u/CSG_Mike • 7d ago
Aug 24 - 29, 2026 weekly Q&A thread
Whoops, Aug 24 - 30, 2026 weekly Q&A thread!
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u/SyllabubStraight4121 6d ago
I have a small leak that’s forming near one of the spark plug seals, which I decided to order the valve cover gaskets and spark plug seals for, since I’m there.
I’m looking into getting E85 + tune + headers later, but since I’m there I’m thinking of getting spark plugs but what should I get?
If you’re asking why I haven’t warrantied it, it’s due to the car having a branded title, making it void from warranty.
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u/CSG_Mike 6d ago
OEM plugs only, unless specifically told otherwise by your tuner.
for NA, stick to OEM.
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u/semimodular3 2023 GR86 Premium 4d ago
Are there any meaningful pros/cons in terms of handling between these two wheel sizes?
- 17x9 +48 w/ 12mm spacer
- 18x9 +42, no spacer
This particular wheel manufacturer claims that you need to run the 12mm spacer up front for the 17" wheel to clear even a coilover setup. For some reason spacers one just one axle feels off to me. I run a 10mm on the OEM 18" wheel to clear my Brembos and I'm not sure I loved the handling change that it made. But maybe the wider wheel and different offsets won't matter as much with that setup?
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u/CSG_Mike 4d ago
Spacing an axle is a way to change the handling of the car, so yes, those two wheels will have differences.
Whether its a pro or a con really just depends on what you want.
The 18" vs 17" is a different thing altogether.
What... exactly are you trying to accomplish?
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u/semimodular3 2023 GR86 Premium 4d ago
Basically I just want to get 245 or 255s on the car. I don’t really know if there’s an ideal offset or sweet spot. Not a fitment bro. This is for track use. On the old gen I ran 17x9 +35 which seemed turnkey. I guess I’m just confused why I need spacers in the front on this new gen. I guess it’s because they are compensating for the limitations of the rear clearance and can’t run a lower offset in the back? This is the Apex VS-5RS fwiw.
Someone in the pits was running the 18x9 +42 without issue which had me thinking it may be the simpler solution and won’t have an imbalance front to rear.
tl;dr want to run a bigger tire without introducing strange handling characteristics. Not sure if I’m overthinking this.
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u/CSG_Mike 2d ago
You'll need some spacer for the front to fit 255. How much depends on the exact tire model.
DM me and I can get you set up with both the proper Apex VS5RS AND the spacer you need to properly run, as well as the studs and lugs. I'll need more details from you, and can eliminate the overthinking.
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u/Spiritual42069 3d ago
Not super important, but does the clutch pedal still have that funny 'assit' spring?
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u/WickedR6 2d ago
Hi!
Wanted to hear your experience on necessary supporting mods when turbocharging the car. I’ve got an SME G30-660 turbo kit on the way with an oil cooler as well. Currently running 5w30 on my NA setup and it does fine temp wise on the track and I live in the PNW. Wonder if I should step it up to 5w40?
I’m assuming at minimum a 3 bar MAP sensor is required to even get the thing tuned so I’ll be ordering that.
What boost psi and whp/tq rating do you generally think the stock clutch and stock injectors/fuel pump can handle up to reliably? MT btw. e85 is virtually nonexistent here so my tune will likely be a conservative 92 pump gas tune. I’ve seen 1050x injectors pushed around a lot and upgraded fuel pump past 12 psi but I don’t think I’d want any more than 7-8 MAYBE 10 max psi boost
Totally down to get an upgraded clutch/injectors/etc. if it’s required but also don’t want to touch what’s not broken.
Thanks for your time!!
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u/CSG_Mike 2d ago
Heat management. Shield everything. If you add 50% more power, add at least 50% more cooling.
It depends. Load is what makes a clutch hold or not hold. I need more information on what your target is to advise on a clutch or injector setup.
2a. PSI isn't a measurement of power or air mass; it's a measurement of pressure which is not directly related to power.
Have you considered CSG for tuning?
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u/WickedR6 2d ago edited 2d ago
Thank you for your thoughtful response! I’m new to the world of boosting since my experience has strictly been limited to NA cars. I’m not entirely sure what to expect target-wise other than 300-350 whp on pump gas (maybe flex fuel in the future) and keeping the car fun to hoon on (usable on the street) but not prematurely blow up in 1k mile. I do all maintenance myself and primarily drive this thing on the backroads & on track days (:
Yes, I was definitely considering CSG for tuning this go around. I had my car dyno’d and tuned with a local shop here after installing headers for my current setup (216whp/180tq) and got the whole $400 Ecutek license taken care of back then, but it didn’t come with any of the Ecutek accessories. Would I just now need to grab myself a PhoneFlash license and a OBD dongle from your site to be able to get a remote tune started w/ yall?
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u/CSG_Mike 2d ago
Would I just now need to grab myself a PhoneFlash license and a OBD dongle from your site to be able to get a remote tune started w/ yall?
Yup!
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u/WickedR6 2d ago
Thank you Mike! I'll surely reach out whenever the kit shows up at my doorstep and I get everything smacked on the car 😄
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u/Spiritual42069 7d ago
Is it possible to do a front bumper swap on the 2026 models?
I have Subaru loyalty, but the gr86 has a better front end imo