Michelin Pilot Sport Cup 2's vs Bridgestone Potenza RE-71R's

I never thought I'd ever run Michelin Pilot Sport Cup 2's on my 2012 Boss 302. The cost is astronomical and they are supposed to last the least of anything comparable. So how did I end up with (nearly) fresh Sport Cup 2's? A complete fluke. I came across a lightly used set with only a few hundred miles and no track time; 305/30/19 takeoffs from a GT Performance Pack Level 2 (GT PPL2). I knew my 71R's were getting very worn before the season started and likely wouldn't last the whole season, even this short one.

The price was far better than a new set of RE-71R's, a little more than half, and local Time Attack rules (Canadian Automobile Sport Clubs) recently made 180 and 200 TW tires equivalent, meaning no PAX or PIP point penalty for going with 180 TW tire like the Pilot Sport Cup 2's. I have been very curious about how PSC2's compare to RE 71R's but I stayed away due to their being painfully expensive and, up to last year, their 180 TW rating would have bumped me up a class. With price and PAX/PIP points not being an issue for a takeoff set, I pulled the trigger and they were at my door a week later.

Size Matters

Of course, the first thing you do when you receive a brand new set of tires is compare heights! Stacked up, they measured about 49.5", almost exactly 1" wider overall than RE 71R's. That also means they are almost exactly 315/30/19 tires if going by a direct conversion, and they were not even mounted whereas the 71R's were mounted when I stacked them. This was a good first impression. The other good first impression was how wide and minimally grooved the outside shoulder is.

Quick heavy cars like Mustangs', Camaro's, M3's, etc. put huge amounts of load on outside shoulders and the Boss 302 is no exception. Wide tread blocks with little grooving suggested to me that they would handle the abuse relatively well (historically a weak point for street Michelin's) and have good response. They absolutely did not disappoint in that regard.

First Impressions

After the first drive was in the rain, it left two very strong impressions. Very good wet grip (no puddles or standing water, just rain, so can't comment on hydroplaning resistance) and excellent steering response. Compared to RE-71R's, the Cup 2's felt telepathic. You touch the steering wheel, and the car starts to turn. That was fantastic when you want it, but it has a downside. Tramlining was an order of magnitude worse than the 71R's which, when combined with the much faster steering response, made them feel nervous on the highway. If you have to choose between these tires for strictly street driving, the RE 71R's would be better (I would recommend neither for strictly street driving, but I know some people do that).

2012 Boss 302 at Atlantic Motorsport Park 2020 T/A Championship - Liev Ryan ©

On track, however, the improved steering response was fantastic. When combined with better feedback, it made the car feel easier to push. It encourages you to trail brake a bit deeper, so you stay in the power longer and carry more speed into a corner. The 71R's also seemed to breakaway a little more abruptly whereas the Cup 2's were more progressive, helping confidence in corner exit as well.

On the other hand, the Cup 2's felt like they definitely had less longitudinal grip - traction - at least in colder temps. During the morning Time Attack sessions, it was much easier to spin compared to the RE-71R's in similar conditions (cool temperatures and overcast). Wheel/axle hop was also worse than RE-71R's so leaving the pits I had to really feather the throttle. Later in the day when it warmed up, axle/wheel hop wasn't that pronounced anymore but the car still felt a little more neutral than on the 71R's, although that could just be subjective due to the faster steering response. So far, subjective impressions are:

1. Good in the wet, comparable to 71R's (absent puddles or standing water, which I have no experience with on either tire).

2. Better steering response than 71R's

3. Bad tramlining, almost nervous on the highway

4. Less traction and harder compound at cool temps, leading to more axle/wheel hop.

5. More progressive loss of traction, good feedback at the limit.

Lap Times

Objective comparison? Well, at face value, it would seem like the Sport Cup 2's are in a league of their own but the reality is that the 71R's were on their last leg. And that leg was broken. This isn't really a fair comparison by a long shot as far as lap times go. In warmer weather, in HPDE setting (longer sessions as I was tuning damper settings), the RE-71R's set a best lap time of 1:17.02 as they were on their way out (they corded in several spots at the end of that very session). A couple of weeks later, my first time driving on the the Sport Cup 2's in a cool morning Time Attack session (about 54 deg F/12 deg C and overcast), that dropped to 1:15.52 with a few other 1:15 laps, suggesting it isn't a one lap wonder. The best lap is a whopping 1.5 s drop on a 77-second lap (excluding out- and in-laps):

Session 1

Conditions: 52 deg F/11 deg C, overcast

Tire pressure: 36 psi hot

Lap 1: 1:16.296 (first hot lap ever on these tires)
Lap 2: 1:15.639
Lap 3: 1:15.523

Session 2

Conditions: 54 deg F/12 deg C, overcast

Tire pressure: 37 psi hot

Lap 1: 1:15.643
Lap 2: 1:16.036
Lap 3: 1:15.979

For that best lap of 1:17.02 lap on the 71R's, conditions were different: approx. 65 deg F/18 deg C on the readout, and sunny. Looking at some of my lap time data over the last couple two seasons, I lose about half a second every 10 deg F (all else being equal) so that 1:17.0x might have been a 1:16.5 judging by temperatures on both days, plus or minus a tenth or two. Then you have to account for old vs fresh RE-71R rubber. On the stock suspension last season, the 71R's lost approximately 0.7 s from new to later days with more heat cycles so that 1:16.5 might have been a 1:15.8, plus or minus, on that same day with new tires which would put it very close to the Cup 2's. At the very least, I think a very low 1:16.xx would be doable on fresh 71R's in cooler temps as the car sits now.

One noticeable difference, however, is how much tire marbles the Sport Cup 2's pick up, even in comparison to sticky fresh 71R's. If the above estimates are true on the fast end (mid-high 1:15.xx lap time range) and the two tires really are close in terms of ultimate performance, it could be that they achieve their performance differently with the 71R's being a softer compound that generates more of its grip by deformation (interlock with road surface) vs the Cup 2's which could be a harder/stiffer compound that is more sticky (more grip due to adhesion as it gets hot). That would make sense given their main purpose; the 71R's ultimately an autocross tire that needs to work cold and the Cup 2 is an OEM trackable street tire. 

Of course, those estimates are no way to figure out a lap time for a tire... the way to do it is to get a fresh set on the car and run it. But taking into account weather and heat cycled worn tires makes it seem at least possible that the two tires would be close. From behind the wheel, it feels that way as well. I think ultimate lap times would be comparable but with very different attitudes. The 71R's are a bit more secure but relatively numb. The Cup 2's are relatively more responsive and neutral.

Finally, one other difference is that Sport Cup 2's like more pressure. They seemed to run well at 36-37 psi hot while the 71R's got greasy quickly at pressures higher than 34 psi. I haven't had a chance to really push the Cup 2's in a long 15-20 minute session to see how bad they get those higher pressures but they do seem to like higher pressures.

Verdict

I'm not sure when or if I will be going back to 71R's because the Sport Cup 2's are a great value. Wear so far after an "easy" day - three time attack sessions and one short lapping session (picture above of the two front tires) - is not bad at all. With rotation, I see getting 8-10 "easy" days out of a set, less with longer lapping/HPDE days. As long as I can continue to find low mileage GT PPL2 or Mach 1 takeoff sets for a good price, I probably will keep using them. I wouldn't hesitate to run RE-71R's again if Bridgestone sent me a set of 305/30/19 RE-71R's to put head to head with the Sport Cup 2's... but I won't hold my breath for that. With that said, I will be able to get a much better apples to apples comparison next season as the Sport Cup 2 wear and get more heat cycles on them so if you are curious how they compare under similar conditions and wear/heat cycles, make sure to follow for updates next season!

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Michelin Pilot Sport Cup 2's vs Bridgestone Potenza RE-71R's

I never thought I'd ever run Michelin Pilot Sport Cup 2's on my 2012 Boss 302. The cost is astronomical and they are supposed to last the least of anything comparable. So how did I end up with (nearly) fresh Sport Cup 2's? A complete fluke. I came across a lightly used set with only a few hundred miles and no track time; 305/30/19 takeoffs from a GT Performance Pack Level 2 (GT PPL2). I knew my 71R's were getting very worn before the season started and likely wouldn't last the whole season, even this short one.

The price was far better than a new set of RE-71R's, a little more than half, and local Time Attack rules (Canadian Automobile Sport Clubs) recently made 180 and 200 TW tires equivalent, meaning no PAX or PIP point penalty for going with 180 TW tire like the Pilot Sport Cup 2's. I have been very curious about how PSC2's compare to RE 71R's but I stayed away due to their being painfully expensive and, up to last year, their 180 TW rating would have bumped me up a class. With price and PAX/PIP points not being an issue for a takeoff set, I pulled the trigger and they were at my door a week later.

Of course, the first thing you do when you receive a brand new set of tires is compare heights! Stacked up, they measured about 49.5", almost exactly 1" wider overall than RE 71R's. That also means they are almost exactly 315/30/19 tires if going by a direct conversion, and they were not even mounted whereas the 71R's were mounted when I stacked them. This was a good first impression. The other good first impression was how wide and minimally grooved the outside shoulder is.

Quick heavy cars like Mustangs', Camaro's, M3's, etc. put huge amounts of load on outside shoulders and the Boss 302 is no exception. Wide tread blocks with little grooving suggested to me that they would handle the abuse relatively well (historically a weak point for street Michelin's) and have good response. They absolutely did not disappoint in that regard.

After the first drive was in the rain, it left two very strong impressions. Very good wet grip (no puddles or standing water, just rain, so can't comment on hydroplaning resistance) and excellent steering response. Compared to RE-71R's, the Cup 2's felt telepathic. You touch the steering wheel, and the car starts to turn. That was fantastic when you want it, but it has a downside. Tramlining was an order of magnitude worse than the 71R's which, when combined with the much faster steering response, made them feel nervous on the highway. If you have to choose between these tires for strictly street driving, the RE 71R's would be better (I would recommend neither for strictly street driving, but I know some people do that).

2012 Boss 302 at Atlantic Motorsport Park 2020 T/A Championship - Liev Ryan ©

On track, however, the improved steering response was fantastic. When combined with better feedback, it made the car feel easier to push. It encourages you to trail brake a bit deeper, so you stay in the power longer and carry more speed into a corner. The 71R's also seemed to breakaway a little more abruptly whereas the Cup 2's were more progressive, helping confidence in corner exit as well.

On the other hand, the Cup 2's felt like they definitely had less longitudinal grip - traction - at least in colder temps. During the morning Time Attack sessions, it was much easier to spin compared to the RE-71R's in similar conditions (cool temperatures and overcast). Wheel/axle hop was also worse than RE-71R's so leaving the pits I had to really feather the throttle. Later in the day when it warmed up, axle/wheel hop wasn't that pronounced anymore but the car still felt a little more neutral than on the 71R's, although that could just be subjective due to the faster steering response. So far, subjective impressions are:

1. Good in the wet, comparable to 71R's (absent puddles or standing water, which I have no experience with on either tire).

2. Better steering response than 71R's

3. Bad tramlining, almost nervous on the highway

4. Less traction and harder compound at cool temps, leading to more axle/wheel hop.

5. More progressive loss of traction, good feedback at the limit.

Objective comparison? Well, at face value, it would seem like the Sport Cup 2's are in a league of their own but the reality is that the 71R's were on their last leg. And that leg was broken. This isn't really a fair comparison by a long shot as far as lap times go. In warmer weather, in HPDE setting (longer sessions as I was tuning damper settings), the RE-71R's set a best lap time of 1:17.02 as they were on their way out (they corded in several spots at the end of that very session). A couple of weeks later, my first time driving on the the Sport Cup 2's in a cool morning Time Attack (short) session, that dropped to 1:15.52 with a few other 1:15 laps, suggesting it isn't a one lap wonder. The best lap is a whopping 1.5 s drop on a 77-second lap:

1:16.296 (first hot lap ever on these tires)
1:15.639
1:15.523

1:15.643
1:16.036
1:15.979

Now, about that 1:17.02 lap on the 71R's. That was in warmer weather than these sessions and looking at some of my historical lap times, that 1:17 might have been a 1:16.5, plus or minus a tenth or two judging by temperatures on both days. Then you have to account for old vs fresh rubber. On the stock suspension last season, the 71R's lost approximately 0.7 s from new to later days with more heat cycles so that 1:16.5 might have been a 1:15.8, plus or minus, on that same day which would put it very close to the Cup 2's. At the very least, I think a very low 1:16.xx would be doable on fresh 71R's in cool temps as the car sits now.

One noticeable difference, however, is how much tire marbles the Sport Cup 2's pick up, even in comparison to sticky fresh 71R's. If the above estimates are true on the fast end (mid-high 1:15.xx lap time range) and the two tires really are close in terms of ultimate performance, it could be that they achieve their performance differently with the 71R's being a softer compound that generates more of its grip by deformation (interlock with road surface) vs the Cup 2's which could be a harder/stiffer compound that is more sticky (more grip due to adhesion as it gets hot). That would make sense given their main purpose; the 71R's ultimately an autocross tire that needs to work cold and the Cup 2 is an OEM trackable street tire. 

Of course, those estimates are no way to figure out a lap time for a tire... the way to do it is to get a fresh set on the car and run it. But taking into account weather and heat cycled, worn tires makes it seem at least possible that the two tires would be close. From behind the wheel, it feels that way as well. I think ultimate lap times would be comparable but with very different attitudes. The 71R's are a bit more secure but relatively numb. The Cup 2's are relatively more responsive and neutral.

Finally, one other difference is that Sport Cup 2's like more pressure. They seemed to run well at 36-37 psi hot while the 71R's got greasy quickly at pressures higher than 34 psi. I haven't had a chance to really push the Cup 2's in a long 15-20 minute session to see how bad they get at higher pressures but they do seem to like higher pressures so far.

I'm not sure when or if I will be going back to 71R's because the Sport Cup 2's are a great value. Wear so far after a short day - three time attack sessions and one lapping session (picture above of the two front tires) - is not bad at all. With rotation, I see getting 8-10 "easy" days out of a set, less with longer lapping/HPDE days. As long as I can continue to find low mileage GT PPL2 or Mach 1 takeoff sets for a good price, I probably will keep using them. I wouldn't hesitate to run RE-71R's again if Bridgestone sent me a set of 305/30/19 RE-71R's to put head to head with the Sport Cup 2's... but I won't hold my breath for that. With that said, I will be able to get a much better apples to apples comparison next season as the Sport Cup 2 wear and get more heat cycles on them so if you are curious how they compare under similar conditions and wear/heat cycles, make sure to follow for updates next season!

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Pedders eXtreme xA Coilover Kit (S197 2005-2014 Mustangs) First Impressions & Installation

If you've been following me, it's no secret by now that I recently got a sponsored set of Pedders eXtreme xA Coilovers to test, thanks to American Muscle. I have been wanting to do something about the stock suspension on my 2012 Boss 302 for a while but budget didn't allow. When the opportunity came knocking, I couldn't be happier. The kit includes coilovers only up front to replace the stock struts but maintains the separate "divorced" damper (shock/shock absorber) and spring setup in the back, a common solution for plenty of entry level/budget coil over options as well as more established brands like KW and Eibach until you get to their flagship or race kits. Even the Maximum Motorsport (MM) JRi coilover kit - a package that is far from a budget or mild street option - retains the divorced spring/damper mounting.

While a true coilover setup in the back would be better, it would be more expensive and at this price point, I think the money is better spent on the damper itself rather than a coilover design. Plus, the divorced spring/damper setup separates forces going through the spring vs the damper. The factory developed Boss 302S and Boss 302R cars used true coilovers in the back but tied the top of the rear damper/shock mount to the cage to reinforce the mounting point. Absent reinforcement and/or a thoroughly tested upper pad design with no failure, there is an increased risk of cracking or failure so its best avoided in my opinion in a budget option.

Specs

With that out of the way, let's get straight to the kit itself. In addition to the coilovers and springs and dampers/shocks in the back, it comes with shortened front sway bar end links and coilover spanners/wrenches for height adjustment. First off, let's start with specs:

Pedders xA front spring rate: 7 kg/mm - 392 lb/in.

Pedders xA rear spring rate: 5 kg/mm - 280 lb/in.

Compared to the stock Boss 302 spring rates:

Stock Boss 302 front spring rate: 2.6 kg/mm - 148 lb/in.

Stock Boss 302 rear spring rate: 3.3 kg/mm - 185 lb/in.

Given the same mounting setup in the back (i.e. separate spring/damper in stock mounting locations) and a solid axle, motion ratios are the same in the back. Front motion ratio would be slightly different due to the drop and possible camber (if you get the camber plates, more on that below), but at stock height and stock camber, it is also virtually unchanged. Given essentially unchanged ratios compared to stock, there is a very clear change to the stock handling balance with all else being the same. This is also true for S197 stock/base GT, Brembo/Track Pack GT, and Boss 302 Laguna Seca, all of which have different spring rates but still use numerically higher (stiffer) spring rates in the back than the fronts. 

The reversal in stiffness balance front-to-rear is the status quo for all mainstream S197 aftermarket lower springs, though, (i.e. Ford Performance, Steeda, Eibach, SR, H&R, and BMR) or coilover kits. The spring rates in this kit are significantly stiffer than the majority of lowering springs as you'd expect but they are on the softer side for a coilover setup which makes the rates a great match IMO for dual duty street/track setups without big aero.

My 2012 Boss 302 in 2019 (stock suspension) - T8 at Atlantic Motorsport Park - Kevin Doubleday©

Unfortunately, I don't have more specs to give you. I requested shock dyno results/graphs from Pedders but they said that was confidential. This is not unusual for shock/damper manufacturers to not share but it would have been nice to see before committing to the kit for moderate to heavy track use, especially if buying outright.

Adjustability 

For a car that will see track time, the most important thing to know is that the S197 Pedders eXtreme xA coilover kit does NOT come with adjustable front coilover mounts. Pedders does offer S197 eXtreme XA camber plates but they are sold separately which are a must for a car seeing regular track time. Fortunately, whether you get just the coilovers or the camber plates, you don't have to worry about compatibility or fitment depending the S197 year and whether you have the early strut mounts (05-10) or newer (11-14). The non adjustable mount with the kit and the camber plate do away completely with the factory strut mount as you would with a coilover kit.

Aside from the camber plates, the package has plenty of adjustability built in. Height is adjustable from 1-3" both front and back compared to a standard GT according to Pedders. On a Boss 302 like mine, you can maintain stock height up front if you want, but you'll have a minimum drop of approx. 1" in the rear with the adjustable spring perches set to their max height. For a starting point to try to maintain stock geometry and clearance for my driveway, I left the rear at their max height (1" lower than stock) and dropped the front approx. 1/2". 

On a side note, if you have the stock driveshaft, you don't have to worry about pinion angles and potentially needing an adjustable rear upper control arm, but you would need at least an adjustable panhard bar to recentre the rear axle with a wide tire setup. However, I would strongly recommend a Fays2 Watts Link. You will never have to worry about adjusting a bar every time you make a small drop, it makes the car far more approachable and settled over bumps, and I have had mine for several years with countless track days and it shrugs off any sort of abuse you can throw at it with fantastic support, plus offering additional tuning by allowing you to move the rear roll centre.

The dampers are adjustable for both compression and rebound, although not separately. Pedders touts that they are monotube dampers which makes for good PR but whether they will hold up like a more premium twin-tube design such as Koni remains to be seen (make sure to follow for updates!). Both fronts and rears have 30 positions with nice distinct detents for each position and each position stiffens or softens compression and rebound at the same time.

Adjustability is also very easy and accessible for damper settings and ride height. A knob at the top of each damper/shock adjusts stiffness and you can access the front coilover height adjustment without affecting preload or taking it off the car, you just have to jack/lift the car, take the wheels off, and loosen the locking ring at the base of the threads, and screw the threaded damper/shock body into or out of the coilover sleeve to lower or raise the front. Likewise in the back, the adjustable spring perches are accessible just by jacking/lifting the rear end and taking the wheels off. 

The camber plates are unfortunately not as accessible. I had Maximum Motorsports (MM) Caster/Camber plates up until now on the stock struts and they (like plenty of other motorsport/track focused products) allow adjustment without dropping the struts, but the Pedders camber plates don't. The top of the strut tower conceals four nuts that lock the bottom plate the coilover mounts to to the top plate that mounts to the car/the strut tower. It's a simple universal design that Pedders (and others) uses across multiple platforms likely for cost and only customizes the shapes of the plates to suit the application/specific car.

As a result, this is more of a "set it and forget it" camber plate unless you feel like jacking your car up at the track, dropping the strut, and dialing more or less camber. I suspect that won't hurt them, though, since the camber plates are not marketed as a standalone upgrade and neither should they be. They are only compatible with the Pedders coilovers. On the bright side, they do have a good range of adjustability which I will talk about in the next post.

Installation

I decided to find an installation video and follow it. With the help of a good buddy of mine and his garage/lift, the install took about 2.5 hours (except for the rear dampers which would not have taken any longer but more on that in a sec).

 

I found more than one installation video on YouTube but unfortunately they all didn't detail a step in the rear damper installation. While the front coilover doesn't use any stock components aside from hardware/fasteners, the rear damper uses the factory rubber pad/mounts and I had two issues with that:

1. The damper rod for the Boss 302 is a larger diameter (thicker) than the GT. Since this kit is built around the GT dampers, the top washer/bushing assembly was too wide for the threaded end. I needed GT mounting bushings/nuts (stock Tokico rear damper/shock on the left with stock Boss 302 upper mount bushing and Pedders rear damper/shock on the right with stock Mustang GT upper bushing/nut assembly above). This is why we couldn't finish the installation the first time through. We wrapped it up with the Pedders  coilovers and sway bar end links up front and Pedders springs and perches in the back. 

2. The Pedders washer on the damper side (i.e. where the bushing on the damper side mounts to the chassis) is very small. The rubber bushing itself would have a very small seating area as a result compared to factory dampers/shocks (above on the left) which have a large seat right into the body of the damper/shock. I didn't like the Pedders washer at all (below). 

For the rear damper install, I picked up a couple different parts; I bought genuine OEM upper bushing/washer assembly for a stock GT from our local Ford Dealer (pictured above) so it could match the size of the threads on the Pedders rear damper/shock body. I also bought Monroe OEM equivalent dampers/shocks from a local parts store as a back up to make sure I had all mounting hardware/bushings just in case. I ended up using bits of both.

Each Monroe replacement damper/shock came with two round rubber bushings, two large washers, and a top mounting nut. I liked those larger washers much better than what came with the Pedders kit (pictured below is one of those rubber bushings and one washer on top of the Pedders washer for size comparison). 

I was going to use those round bushings that came with the aftermarket damper (above) which felt a bit stiffer than factory, but after mounting it I found the damper rod tilted towards the inside of the trunk. I ended up using the factory lower bushing that came with the car since they had a self centring boot (two pictures up) that ensured the damper/shock is centred in the chassis mounting hole for even distribution of loads to the chassis mounting point/pad (pictured below). I combined that with the large aftermarket washers (above picture) due to their thickness and far larger diameter, and took out the Pedders small washers. Finally, I used the Ford OEM GT upper bushing/washer assembly that I had picked up from the dealer (three pictures up).

Swapping the rear shocks was simple which I did a few days later in my driveway once I had all the parts. You just undo the rear sway bar end links to rotate the sway bar out of the way, undo the upper and lower mounts for the dampers, and slide the damper out as you can see in the video. With that done, the car was finally ready for an alignment and corner balancing. Stay tuned for the next post very soon covering the track setup including alignment and corner weights, as well as review on the street and the track.

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C8 Corvette Z06, ZR1, and ZORA engines and hp leaked!

GM recently announced that the high performing C8 Corvette models that have been highly anticipated are going to be delayed because of the ongoing pandemic. As a result, some GM insiders saw fit to leak some details about the upcoming (and highly anticipated) big gun C8 Corvette models. According to a report by Hagerty, the usual Grand Sport, Z06, and ZR1 are planned as has been rumoured, in addition to a top of the line hyper-car level model named Zora, also as rumoured. And now, we get a sneak peak into what they may be packing.

Z06: 600 hp - 470 lb-ft

The Z06 will supposedly get the highly anticipated 5.5 litre flat-plane crank DOHC V8 that debuted in the C8.R race car. You can hear it rev here where it certainly sounds a lot more exotic, if less baritone than the traditional Corvette noise. The new engine will be code named LT6 and Hagerty's estimates put the power output around 600 hp. If it follows a similar specific power to the 5.2 litre Voodoo V8 in the Shelby GT350, it will have just over 550 hp. I suspect GM will be going for “bragging rights” and getting 600 hp from a naturally aspirated 5.5 litre sounds like a really nice round number. Keeping it naturally aspirated will also mean “return to form” for the Z06 following the C5 and C6 (and the original and extremely rare nearly race-ready C2 Z06). After the supercharged C7 Z06, a lot of people have been asking for the Z06 to be simpler, more raw, and much more focused on track and it sounds like this might happen.

Grand Sport: 600 hp - 500 lb-ft

For the last two generations, the Grand Sport has been a Z06 “light”, using the same powertrain as the entry level Corvette but the wide body and a lot of suspension and brake bits from the Z06. It seems like that will change for the C8. While the engine itself is the same small block LT2 6.2 litre V8, it appears to be getting hybrid assist bumping power to an estimated 600 hp. No information is given about the hybrid system, but I suspect it will be what is typically called “mild hybrid” where you may get a larger alternator that can act as an alternator or generator to capture regen, perhaps combined with a 48V battery with enough capacity to capture and store some regen energy and then power the alternator/generator for bursts of power to supplement the gas engine. 600 hp estimate seems on the high side to me for total power, I suspect it will be around 550 hp. I think 600 hp might step on the Z06 toes a bit.

ZR1: 850 hp - 825 lb-ft

The ZR1 is going to use a version of the same flat-plane 5.5 litre V8 used in the Z06, but this one will have a couple of turbos strapped to it like the Blackwing V8 found in the shortly lived Cadillac CT6-V. I seem to remember GM saying that it's not the same engine, although it could share some parts. It sounds like no one will be missing the Cadillac version, though, since this one is anticipated to produce a whopping 850 hp. It's code named LT7 and it means the ZR1 will play in the same sandbox as cars like the Lamborghini Aventador, Ferrari 812 Superfast, and the McLaren 720S while being able to claim the highest hp. One other trick up its sleeve may be active aero. This could come on the Z06 as well, but it would be even more useful here with that much power. That's one piece of tech that was anticipated on the C8 Corvette based on patent filings before it debuted, which showed very capable active aero systems, but we have yet to see any applications.

Zora: 1,000 hp - 975 lb-ft

The top of the line hyper-car-beating model will be the Zora, named after Zora ‘the father of the Corvette’. The Zora will essentially build on the ZR1 drivetrain, using a version of the LT7 twin-turbo 5.5 litre V8 and supplementing it with a hybrid system. I suspect this one will have no chance of being a mild hybrid, however, but details are scarce. Multiple rumours suggest this one will be AWD and that makes a lot of sense for simplicity.

Putting an electric motor up front to power the front wheels will easily allow electric only driving mode (albeit, as a FWD... but the Porsche 918 and Acura NSX can do the same). It will also keep the engine and transaxle fairly "simple" without the need to add an electric motor or sandwich one between the engine and the transmission. Finally, it also means the car will be AWD without the need for a second driveshaft or takeoff from the transaxle to send power up front. If all stands to be true, that will make the Zora a hybrid, twin-turbo V8, mid-engine AWD Corvette, a combination of developments and changes I never expected to see happen all within one generation of Corvette. The car will likely be an absolute monster and should be one of the fastest accelerating and highest performing production cars available. Total output of the engine and electric motor are estimated at around 1,000 hp.

On-Sale Date?

According to the leaked info, the Z06 was slated to be a 2022 model years, meaning it likely would have gone into production and went on sale some time in the next year. The Grand Sport, ZR1, and Zora would then be release one by one, each one year apart (i.e. 2023, 2024, and 2025). With plans on hold, it’s unknown when they may go back into production, or (and this is a very bleak scenario) if they will go into production at all if no case could be made for them after normalcy is resumed. Only time will tell. As was the case for production, no cost estimates are provided, but I suspect the Z06 will be very close to $100k, the ZR1 will be close to $150k, and the Zora may approach $200k.


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Rams Eye New Track Car & Daily Reveal

New track car? You bet! Just picked it up a few weeks ago for a long term test to serve as a dual purpose daily and track car. It's a bit obscure and forgotten about but packs a lot of special features and one of the best AWD systems you can buy. Watch to find out what it is, why it's forgotten, and what I like the most about it (plus how much I paid for it!).

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Koenigsegg Gamera: 4 Seats, 4WD, 3 Cylinders, and 1700 hp

Meet the Koenigsegg Gamera. This car brings so many firsts, not just to Koenigsegg, but also to the entire automotive industry. For Koenigsegg, it is the first car to have 4 seats, the first to have 3 cylinders and the first to have all wheel drive. Koenigsegg calls it the world's first mega-GT (gran touring) car, and I think they're right. For the world, it brings the first four seater, mid-engine, hyper car. Koenigsegg says it wants to bring the "exciting performance traits of a mid-engine two-seater megacar with the practicalities of a four-seater car with more luggage space" so the experience can be shared with "family and friends." Clearly, I need better friends...

With 1,700 hp on tap, you are sure to impress those lucky enough to be your family and friends if you own one of those. Of course, a three cylinder engine with 1,700 hp is likely to have all the driveability and flexibility of a farm tractor so Koenigsegg doesn't rely on it for all the oomph. Still, the 2.0 litre 3-cylinder engine makes an astonishing 600 hp at 7,500 rpm with a redline of 8,500 rpm and 443 lb-ft from as low as 2,000 rpm to 7,000 rpm. Appropriately named Tiny Friendly Giant (TFG), everything about the engine is astonishing.

It weighs a measly 154 lb. which is unheard of for that much power among production cars. For reference, one of the most compacts and power dense engine out there is is Chevy's small block V8, thanks to a single cam-in-block design (i.e. overhead valves or pushrod engine). It weighs around 430 lb. Ford's tiny 1.0 litre 3-cylinder EcoBoost weighs 200 lb. How does Koenigsegg manage to make the engine so light? Well, it doesn't specify if this is dry or wet weight so it might be a little more, but the engine is actually a dry sump design so it wet weight should not add a whole lot. The most likely reason is what Koenigsegg calls Freevalve technology.

Co-developed by Koenigsegg and sister company Freevalve, it is a cam-less design, meaning the engine doesn't have any camshafts controlling intake and exhaust valve. Instead, there are individual actuators for each valve. In essence, valve lift and duration are completely uncoupled from engine rotation, inherently also uncoupling all valves from each other. That means range of operation is much wider, allowing engines to switch combustion cycles and fuels seamlessly. And the amount of optimization possible based on engine load and rpms is massive. Think about what variable valve timing technology did to engines 10-15 years ago, only about a thousand times more flexible. You can watch Christian von Koenigsegg himself explain the tech and its benefits below:

Koenigsegg then throws in its own Engine Control Module combined with in-cylinder pressure sensors instead of relying on traditional knock-sensors, which means that the engine module should determine with much better accuracy if there is any detonation and therefore (likely) run leaner, hotter, with more timing to make more power if required without engine damage.

And as already mentioned, it also means seamless fuel switching. As a result, Koenigsegg says the engine can switch between gas (petrol) and ethanol (up to E100!) with no tuning required. Koenigsegg also says it can run on methanol, presumably meth/water injection capability without tuning but it doesn't specify. They also says it can run on "sun fuel". Not sure what that is. Likely the hopes and dreams of other car manufacturers out there.

What about the rest of 1,700 hp? The rest comes from three electric motors. The way the entire drivetrain comes together is very unique and some details are not explicitly clear from reading Koenigsegg's official info, but you can tell after watching the video a couple of times (below). Essentially, the 2.0 litre engine (TFG) has a 400 hp electric motor connected to the crank. A torque tube connects that electric motor to the front axle and powers the front wheels. In the back, there are two 500 hp, 738 lb-ft electric motors outback, one powering each rear wheel independently.

There is no mechanical connection between the engine and the rear wheels, meaning that the two electric motors in the back are the only way to power the rear wheels. The two electric motors each have an independent gearbox which have reverse gears. The front wheels are connected using similar tech to the Regera hybrid, or direct-drive in Koenigsegg speak. You can read about the technology in more detail here, but in essence, it uses a hydraulic coupling and a set of clutch packs in place of a traditional gearbox just before the front differential. The front differential is a traditional open diff but it uses a set of electronically controlled clutch packs - one on each front half shaft - to independently lock each side.

The front differential and clutch packs essentially work the same way as the rear differential on a Focus RS to provide torque vectoring but with one major exception; there is a mechanical differential in between. Where the Focus RS needs to constantly modulate clutch packs to mimic a mechanical differential (hence the heating issue some people run into on track), the Gamera has a mechanical differential just like any traditional car, and the clutch packs only provide the ability to vary how much torque it sends to each wheel by modulating the clutch packs. Combined with the independent rear electric motors, this gives the Gamera four wheel drive combined with four wheel torque vectoring.

You can read more on the official Koenigsegg Gamera page and watch Koenigsegg's rendering below of the entire drivetrain and battery pack which is very impressive.

The results? 0-100 kph (62 mph) in a scant 1.9 seconds. Top speed of 250 mph (400 kph) and Koenigsegg claims that it reaches that speed in record time, faster than any other production car can. All while offering 50 km electric only range thanks to a 15 kWh 800 V battery pack. But to do that, it does have to decouple the rear wheels... that's right, in range mode, the Koenigsegg Gamera becomes FWD. With that said, the battery pack can discharge electricity at a whopping rate of 900 kW or 1,206 hp so that it can keep up with the combined max power output of the three electric motors.

Wrapping all of this together is a carbon-fibre intensive design. There is a carbon fibre tub with aluminum front and rear subframes attaching the suspension. Body panels are also carbon fibre and the wheels could be made out of carbon fibre if you want. Even the seats are made out of carbon fibre buckets with exposed weaves and they appear to be fixed back, but Koenigsegg is touting comfort thanks to memory foam. The interior is very minimalist with a large centre screen that looks to contain all functions and all air vents appear to be concealed. There are also no side view mirrors. Instead, there are side cameras connected to two side screens and a third screen replacing the dash and gauges. Rear view mirror is likewise replaced with a screen and a rear view camera.

And being Koenigsegg, it's a complete package, not just an exercise in mad power or headline specs. If four wheel drive and four wheel steering is not enough, Koenigsegg also fitted the Gamera with real wheel steering, meaning the Gamera also has four wheel steering. The suspension is double-wishbone front and back. The dampers are, of course, adjustable and the Gamera goes one step further with hydraulic ride height adjustment range of 1.4" (35 mm). Wheels measure 21" x 10.5" up front and 22" x 11.5" in the back. Standard tires are 295/30/21 in the front and 315/30/22 and they are Michelin Pilot Sport 4S. Option tires are the same size, but are sticky Michelin Cup R3's. Standard brakes are 16.3" up front with 6-piston calipers and 15.4" in the back with 4-piston calipers, all carbon ceramics.

And since Koenigsegg is no boutique automaker, you get ABS, traction control with 3 settings (wet, normal, and track), and stability control, in addition to driver assists and a host of luxury features. If you're a regular reader, you probably have noticed that I don't typically comment on all the little features and focus on the mechanical details, but I'm just impressed by how complete the package is. There is a whole host of luxury features, including three zone climate control, heated and cooled cup holders, heated seats, the lot. Despite all of that, Koenigsegg is quoting a curb weight (including fluids) of approx. 4,079 lb (1,850 kg). It's certainly not light, but when you think of cars offering anything this complex (i.e. AWD, four seater, hybrid tech with a battery pack large enough for EV range, over 1,000 hp), it is actually a featherweight.

Koenigsegg hasn't announced pricing yet, but they did say production will be limited to 300. Think you'll be able to afford it? Better let Koenigsegg know you're interested.

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