[cwebster]

Originally Posted by wnta1ss

I think a STOCK M6 Hellcat will be a good race for Cal's STOCK M6 ZL1. I have talked to a drag racer who has an M6 Cat and he told me his best time was 12.0sec.

A bolt-on A8 Cat with Drag Radials is a different story. I've seen one run as quick as 10.7@127 on a cold day.

Interesting... does that Cat racer run stock rims and rubber? Does he have a lot of seat time? I know there are a lot of other factors too - track prep, familiarity with track, weather, concentration, etc.

I've heard those A8 Cat times very recently too, on a warm day (762CAT and company). The A8 makes a big difference, allowing the motor to stay in the peak power band. Of course DRs are going to put more of that power to the pavement.

--Cal

[wnta1ss]

Originally Posted by cwebster

Interesting... does that Cat racer run stock rims and rubber? Does he have a lot of seat time? I know there are a lot of other factors too - track prep, familiarity with track, weather, concentration, etc.

I've heard those A8 Cat times very recently too, on a warm day (762CAT and company). The A8 makes a big difference, allowing the motor to stay in the peak power band. Of course DRs are going to put more of that power to the pavement.

--Cal

The M6 guy was racing a '60s Mopar with a big engine and slicks when I talked to him. I did not see him run the Cat, he told me about it. Supposed to be stock from what I recall.

As far as the A8 Cat with DRs, on a warmer day I saw him running consistent 11.0s while I was there. I have one of the slips. Talked to him on another occasion and he told me he'd run 10.86 I think it was on that day. May have cooled off after I left, I did leave perhaps 2 hours before the track closed. On the coldest day (46~47 according to the temp readout of my car) I saw the 10.75@127 run. Someone I know told me that he did a 10.6 that night but I did not see it myself.

[762CAT]

Cal my man...some encouragement for you that I forgot to mention in my texts. Last weekend at Fayetteville a 2013 GT500 owner sought me out for a race. Cat was running consistent 10.7s @ 128mph so I was pretty confident and that is a race I've wanted. 662 hp king of the curb rockets! The guy was very nice and I checked out his ride and noticed he was on street tires..... I was a little disappointed but here is how this applies to you. I ran a 10.74 and blew his doors clean off. He only ran a 12.2 and his 60ft was in the low 2s on a well prepped track. There was also a Z06 there with the Z07 package on the Pilot Sport Cup 2s...he ran mid/high 11s and I think around 11.6 was his best time.

That tells me at 11.8 on street rubber you are doing very, very well! That Vette is lighter, has 335 wide tires and the PSC2s are very sticky compared to what you are on. Also you are famous...an Audi driver was asking about your car "the ZL1 with the red hood".

Hope to see you again at Cars and Coffee New Bern this Saturday.

[KyleL]

I noticed in all your runs you used lc and came out about 3600. I'm curious though, what was your slip target, did you try other rpms to launch from, did you dump the clutch on lc and rely on the computer or did you try to feather it any and did you try to utilize the no lift shift feature? Based on the pdr footage, you lifted and I'm curious that if you made a run without lifting if it made a difference? I apologize if you answered these questions already, I just didn't see by skimming the thread.

I've noticed that with anything less that a 10% slip target and under a 3500 rpm launch on an unprepped surface, there's too much interference and the car just falls down, THEN chirps through 1st much like your car did. Did you try just maxing the parameters out (4000 rpm launch with a 15% slip target) to see what that'll net? If so, what results did you get?

[cwebster]

Originally Posted by 762CAT

Cal my man...some encouragement for you that I forgot to mention in my texts. Last weekend at Fayetteville a 2013 GT500 owner sought me out for a race. Cat was running consistent 10.7s @ 128mph so I was pretty confident and that is a race I've wanted. 662 hp king of the curb rockets! The guy was very nice and I checked out his ride and noticed he was on street tires..... I was a little disappointed but here is how this applies to you. I ran a 10.74 and blew his doors clean off. He only ran a 12.2 and his 60ft was in the low 2s on a well prepped track. There was also a Z06 there with the Z07 package on the Pilot Sport Cup 2s...he ran mid/high 11s and I think around 11.6 was his best time.

That tells me at 11.8 on street rubber you are doing very, very well! That Vette is lighter, has 335 wide tires and the PSC2s are very sticky compared to what you are on. Also you are famous...an Audi driver was asking about your car "the ZL1 with the red hood".

Hope to see you again at Cars and Coffee New Bern this Saturday.

Hmm... that IS encouraging. Thanks! I still believe 11.7 is possible on stock tires. I would like to try one more session with street rubber on a warm day and well-prepped track but, alas I doubt I have enough rubber left on the rears. I've pretty much worn off the lateral tread grooves so all that's left are the wear-indicator pockets (about 1/8"), besides the rain grooves. I might get 2 or 3 runs out of them before the belts start showing. Then I'd need to drive back home...

I'm ordering my replacement stock F1 G3's today, unless I find better road track tires. I really need to get some drag rims and slicks, though. Not going to burn off another set of stock tires at the drag strip. I'm kind of lost so I'm gonna post the question in the dragstrip discussion group. No speed shops closeby where I could try on 18" rims and I don't want to order and find out they won't fit.

That's cool that random people know about me, huh? I don't know how I'll handle fame. LOL, Maybe once I get consistently faster I'll feel like I'm worthy. For now I'll be satisfied to meet my personal intermediate goals. Drag strip: 10's w/slicks. Ultimately, I'd like to get fastest amateur track time on any road course. It would be cool to be #1 on fast list with only rear wheel/tire mod too.

--Cal

[cwebster]

Originally Posted by KyleL

I noticed in all your runs you used lc and came out about 3600. I'm curious though, what was your slip target, did you try other rpms to launch from, did you dump the clutch on lc and rely on the computer or did you try to feather it any and did you try to utilize the no lift shift feature? Based on the pdr footage, you lifted and I'm curious that if you made a run without lifting if it made a difference? I apologize if you answered these questions already, I just didn't see by skimming the thread.

I've noticed that with anything less that a 10% slip target and under a 3500 rpm launch on an unprepped surface, there's too much interference and the car just falls down, THEN chirps through 1st much like your car did. Did you try just maxing the parameters out (4000 rpm launch with a 15% slip target) to see what that'll net? If so, what results did you get?

I only used Launch Control for the 1st 2 runs. I listed the launch targets for RPM/wheel slip above each video in the OP. Everything after that was full manual. I only used TPM to get the line-lock so I could do a decent burn-out before each run. Then I disabled all automated controls by holding down the Stability Control button for 5-sec. before staging at the tree. I did not try feathering the clutch when using custom LC that I recall. I felt that would defeat the purpose. Manual launch with TPM engaged nearly always badly bogged the motor, resulting in horribly slow 60' and 1/4 times.

I have tried almost every conceivable combination of RPM/slip targets on previous visits to the drag strip. As I said in the initial post, it's nearly impossible to predict the combination necessary to get a perfect automated launch because traction/conditions change from one run to the next. Read the section labeled [Auto/Custom Launch Control] again. Feel free to experiment on your own. You might have better luck than I.

--Cal

[762CAT]

Dude you ate a set of tires in a matter of months!!! HELL YES!!!!

As for 18's that fit I'm no Camaro owner but I'd think some of your 2017 SS owners may be of service. I've seen some on slicks at the track. I would imagine if they fit the SS they'd fit the ZL1???

[cwebster]

Originally Posted by 762CAT

Dude you ate a set of tires in a matter of months!!! HELL YES!!!!

As for 18's that fit I'm no Camaro owner but I'd think some of your 2017 SS owners may be of service. I've seen some on slicks at the track. I would imagine if they fit the SS they'd fit the ZL1???

Yup, Just over 2 months if you wanna know the truth. To properly heat the tires requires a burnout for each run. I could feel my wallet getting lighter with each pass.

Ordinarily I'd seek out a SS 1LE setup for the drag strip but there are no 6th Gen 1LE's yet. Problem is the massive rotors and Brembos do not match the SS. Theirs are much smaller.

2017 ZL1:

Front: 15.3543" (390 mm) x 1.41732" (36 mm) 2-pc rotor w/ 6-piston caliper
Rear: 14.3701" (365 mm) x 1.10236 (28 mm) 2-pc rotor w/ 4-piston caliper

Ref: THE ALL-NEW 2017 CAMARO ZL1

2016 SS:

Front: 13.6" (345 mm) x 1.1811" (30 mm) 2-pc rotor w/ 4-piston caliper
Rear: 13.3" (339 mm) x 1.02362" (26 mm) 2-pc rotor w/ 4-piston caliper

Ref: 6th gen Camaro brake size info - from Brembo site

My best bet would be to go to a speed shop and try some on like a pair of shoes. I called Majestic Motorsports in Hubert, closest shop I know of, but they said they'd have to order and wait for them to come in. That kind of limits my options. I'd be locked in to buy my rims/tires from them.

Wheel Offset (F/R)............20mm / 43mm

According to my references, backspace = offset + 1/2 wheel width + 1/2"
(Ref: Wheel Offset vs. Wheel Backspacing Explained)

ZL1 Rear: 1.69291" (43mm) + 5.5" + 0.5" = 7.69291"




I'm still not sure whether the wheel offset/backspace numbers will be enough to ensure a good fit.

So, as soon as the weather clears I'm getting other measurements like distance from existing rim to nearest suspension components and brake lines. Then I'll ask questions and seek a guarantee that rims will fit my car. If not it'll be no cost to exchange or return.

That still won't tell me whether the Brembo callipers will fit within the 18" rims. I only have 1.25" clearance with stock 20" rims. Also wondering whether I could fit 12" wide rears like they're using on the 2018 ZL1 1LE. Same wheel well but smaller, coil-over brakes so who knows.

Man! I sure wish this could go faster. I feel the need for speed.

--Cal

[762CAT]

Hmmm I can't help you with offsets. I know what they are for the Cat but I will say the Hellcat rear rotors are 13.4 inches so a bit smaller than yours. 17inch rims barely clear but they do. 18s (which I run on the strip) clear very easily. I would be confident 18's would fit over your rotors but based on the above 17's are unlikely.

I'd look at what tire you want to use to as that may influence your rim choice. For example the 305/45R18 Mickey Thompson ET Street R that I run and that so many others use with great success is made to go on a 10inch wide rim. Not so say it won't fit other widths but that is the measuring rim from Mickey Thompson. Most 305 DOT drag radials on 20 inch rims are made for 11 inch wide rims. With the manual car I know you are looking at slicks...but it's worth seeing what tire size/rim combo then you can figure out the offset for the correct rim width........

I'm not sure if that helps or adds more math and work....Lol


You are stuck with the problems of being the 2017 ZL1 pioneer unfortunately.

[big dave]

Glad to see you're still at it Cal. I was wondering what had happened. I don't know how I missed this post over the last couple weeks. I'm glad to see you're improving on your previous best times. I'm absolutely positive that there is an 11.5 or quicker on street tires possible with this car. I can't wait to try for myself.

[cwebster]

Originally Posted by big dave

Glad to see you're still at it Cal. I was wondering what had happened. I don't know how I missed this post over the last couple weeks. I'm glad to see you're improving on your previous best times. I'm absolutely positive that there is an 11.5 or quicker on street tires possible with this car. I can't wait to try for myself.

Hey Dave! There may very well be 11.5's possible on street rubber. I just don't have any more rubber on the rear tires to test that. With warmer track temps coming, I'm guessing it would be easier to improve those 60' times.

I'm going to break down and buy some drag strip wheels/tires instead of wasting more stock rubber.

See the thread 6th Gen ZL1 Drag Strip Wheel & Tire Options for details on how I see my options. Feel free to chime in if you can clear up some of my questions or you can offer some other input.

--Cal

[cwebster]

Originally Posted by 762CAT

Hmmm I can't help you with offsets. I know what they are for the Cat but I will say the Hellcat rear rotors are 13.4 inches so a bit smaller than yours. 17inch rims barely clear but they do. 18s (which I run on the strip) clear very easily. I would be confident 18's would fit over your rotors but based on the above 17's are unlikely.

I'd look at what tire you want to use to as that may influence your rim choice. For example the 305/45R18 Mickey Thompson ET Street R that I run and that so many others use with great success is made to go on a 10inch wide rim. Not so say it won't fit other widths but that is the measuring rim from Mickey Thompson. Most 305 DOT drag radials on 20 inch rims are made for 11 inch wide rims. With the manual car I know you are looking at slicks...but it's worth seeing what tire size/rim combo then you can figure out the offset for the correct rim width........

I'm not sure if that helps or adds more math and work....Lol


You are stuck with the problems of being the 2017 ZL1 pioneer unfortunately.

I've completed measurements under the car and did a lot of research on rims and tires. At this point I'm looking at the following wheel/tire combo but I'd really like to get some closer to the look and construction of my stock wheels.

Weld Tech S76B Wheels

Price:            $705.20
Make:             Weld Tech
Model:            S76B
Size:             18x11
Color:            Chrome with black painted spokes
Backspace/offset: 7.6"/41mm
Bolt pattern:     5x4.75
Pad Height:       high

ET STREET S/S - STREET TIRE FOR THE DRAG STRIP

Size            Wt     cmpnd  rim    sec      tread    O.D.    circ.     Matl #          Part #
P305/40R18
28X12.50R18     33     R2     11     12.2     11.1     28.0     87.9     90000024572     3482

See this thread in the "6th Gen ZL1 Drag Strip Wheel & Tire Options" discussion group for details on my measurements, research, and decision info.

6th Gen ZL1 Drag Strip Wheel & Tire Options

--Cal

[mlee]

Subscribed... love this thread!!!

[cwebster]

Originally Posted by mlee

Subscribed... love this thread!!!

Thanks man! I guess I'll have to do one more trip on stock rubber since my drag wheels / DRs won't be here for about another month. It's been too long already and the itch is getting stronger. Weather looks perfect this coming weekend. I'll be running the car somewhere... I'll post an update afterward.

--Cal

P.S. Please tell me how I can find out what ZL1 sequence number I have. Your signature says you have the #2 A10. I'd like to know what mine is for the M6 with VIN last-8 H0170832 with TPW 12/8/2016.