jn66

Morning all -

has anyone spent anytime upgrading the engine performance or increased HP and still tracked there car a lot?

str8blst

I have Renntech tune, BOV's and track supporting mods . Track the car a fair bit and no issues.

dllhg

Depends greatly on how fast of a driver you are. I’m new to this platform so i don’t know how this car holds up. more power creates more heat. engine heat, trans heat , exhaust heat. Exist heat is something to watch out for. if car is pushed hard it will make a ton of heat. then you are left with how well AMG protected everything. wiring harnesses ,trans lines etc.

jn66

this is a good point. I drive it hard. I’ve been thinking of upgrading the turbos - but may just wait it out and see what’s next. Maybe some of these second market black series prices will dip if we get ourselves into a nice recession haha.

jn66

Thanks man!

dllhg

try a stage 1 tune and see how it holds up on track. i drive hard and run fast times. i’m going to be testing mine shortly. i’ll be mixing at least third race fuel for buffer too. cars are already on bleeding edge for pump gas let alone more boost. Stage 1 tune is 710 hp close to BS 👍

BS down to 500 still too much for the difference

jn66

which stage 1 did you have? I have a eurocharged that’s sitting on the handheld. I need to put it back on.

dllhg

Eurocharged as well. i haven’t even run it personally. just got the car. my CLS63 had one of their tunes and it knocked badly with 91 octane despite being a 91 octane tune. I ran 101 on my stock c7z06. Made a lot more power on drag strip and on road course. more consistent power especially. i’m betting the Eurocharge will run better and safer with more octane.

jn66

ill be running it with 94 (edited here. Fat fingered 104) . Have three days booked 20-22 coming up.

Will report back. Will be running the new black series tires. Unfortunately the gt4 wing will not be installed yet

dllhg

Nice. i’m going next sunday.

What tires are those ?

With GT4 wing how will you balance the front ? too big on either without doing the other can imbalance the car and actually be slower.

jn66

Was hoping the additional front arrow on the Pro model will help. If I find I am slower than I’ll have to sort that haha.

Not sure if this copy and paste will come but these tires

285/35ZR19 (103Y) XL MO1 A A BSW
(MSPN : 27075)
335/30ZR20 (108Y) XL MO1 A A BSW
(MSPN : 05825)
335/30ZR20 (108Y) XL MO1 BSW
(MSPN : 23359)

dllhg

if it’s the Cup 2 R you will be a lot happier and faster with different track tire. great tire for track for a few laps. take time to heat up then have a few good laps and fall off. Jeff Cook recently advised me again at those for that very reason. Told me to try and get the AR1 like i had on my C7Z. amazing all around tire. heat up in half a lap. keep grip for whole session. only lose a second on second day. i’d get four days on them with my similar weighted C7Z. noisy on road before first track day. grip on the street incredibly well too. heat up in a few miles on street and grip like drag radial. got 1.65 60 foots at drag strip with them too. oh and they handle rain just fine. zero drama.

Until i get new wheels i’ll run the 275 front and stretch a 305 on rear. stock gt3 run the same exact size on 12 inch rim from factory.

jn66

I’ll look around for those. Thanks.

inhave some R7s I haven’t used and a set of unset ZPs as well which came on the corvette z07. Used them before and they were great but ripped them apart after two days. Posted photos a year or two back - but grabbed another set anyway as tires were hard to come by for a few minutes.

I need to get a set of dedicated track wheels. 19s squared or 18.

jn66

To run the ar1 I would need a new set of wheels. 18s come in 335, 19s 325. Would run a square setup. Winter shopping list now.

dllhg

i ran 335 /315 18s in my. C7z. I thought 18s wouldn’t work on the GTR.

jn66

Yeah, likely not with the carbon ceramics. Was probably getting ahead of myself - although someone with more knowledge on wheels than me would have to chime in. I thought the gt3/4 ran on 18s but I could be wrong

dllhg

i took carbon ceramics off for AP racing. best track kit you can get for any car imo. nearly 6k per axle. heard some talking about the rear steering motor being in the way too. there is one guy who ran 19s which is what i was planning on. 325 on 12 inch rim is unnoticeable vs the 335. have to see if diameter works. other guy was running slicks.

The AR1 is a small step below a fresh R7 but the R7 won’t be nearly as sticky for at least a couple laps. AR1 heat up like an A7 but without the drop off. neat tire you can safely drive to the track in. i daily mine. still get four track days and i drive hard. Cobalt and raybestos pads would last a single track day on my Z.

WhiteBlack

The engine cooling the the gtr is very good. On cool down laps when the fans are running hard and you've got good airflow but light load you'll see engine temps momentarily fall to 80c or there abouts which is "cold" (this is assuming those readings are accurate of course).

All GTs work the front tyres hard. The heat build up in the fronts is just ridiculous from both the brakes and tyres.

IMO if you're tracking the GTR/PRO/BS you should be more concerned with setup, front brake cooling and learning to drive in a style that suits the car rather than a cheap few extra bhp.

jn66

All good advice. Have the car setup well, Tikt brake ducts have been on for quite sometime as well - also the cage and black series carbon recaro went in last winter.

My Pro has just over 29,000km - much of that on the track since I acquired it November 2019. I would assume that is the highest mileage of any pro around. It’s certainly been driven and this isn’t my only track car.

The additional HP is just for something new. How’s not the time to sell it and get something different imo. I think that time is 6 months from now or so - for me anyways…although I might keep this regardless.

Your advice is sound though.

dllhg

Thats good to know. hoping the cooling system handles the added power from my stage 1 tune okay. will know next sunday. sounds like it will be okay. exhaust heat is my next concern. hoping AMG shielded everything well enough. Also hoping the primary cats don’t melt like they did on my C7Z after 3 months of tracking it hard.

I have the Tikt cooling kit. Recaro seats going in this week ,tires and AP brake kit 👍. anxious to see how she plays on the track.

thebishman

I agree 100% with ‘WhiteBlack’ in that bang for the buck; brake cooling and set up including adequate seats/restraints and alignment along with a dedicated set of 19” wheels in the correct offset to allow you a wider choice of DOT ‘R’ tyres is worth far, far more than a Stage 1 tune. This car does not lack for power on track; in fact more power may be a detriment on some tracks that are more technical in nature.

dllhg

my car came with tune figure i’ll try it out. I Thought about removing initially so i can get used to car first. MY C7Z was way more power than I needed for a while. then i’m started wishing i had more. 120 mph used to scare the hell out of my in T1 at laguna. now 139 isn’t fast enough lol. all what you get used to.

what wheel specs work for the GTR ? i really want tom get some 19s

jn66

Thanks for chiming info BIsh

What specs do you like for 19s all around?

thebishman

I actually went with a set of Signature wheels in the OEM offsets and sizes because 1: I decided when I bought the car to just use the ROW Michelin ‘R’ tyres that were pretty easy to find at that time, as many guys buying the C7 Z06/7 we’re taking off the ZR Cup 2s and then selling them on the Corvette Forum, and 2: since I was going to drive the car from the house to my local tracks I wanted/needed to use a tyre that was street legal.

Now that there are more tyre choices available such as the AR1s, I would follow what others have done and get a custom set of 19”s made F & R in the size and offset to allow me to get as much tyre under the car as possible. As to what those specific measurements would be I unfortunately don’t know them.

jn66

Thank you Sir.