[Ryephile]

The front ride link inner bushing appears to come in two "shapes", the FE2/3/A, and FE4 "big rubber". Given the part numbers are different between the FE2/3 and FEA links, the durometers are likely different.

Apart from that, it appears the only difference with this FEA kit vs. FE4 is the rear knuckles, which are also different part numbers, and I just looked at my factory FE4 knuckles, the outer LCA is indeed a rubber bushing, not a spherical that's in the FEA knuckles. The front "rear" link and the rear trailing links share part numbers between FE4 and FEA.

Since you're coming from FE3 suspension, this kit is exactly tailored for you. For me, the only improvements appear to be the front ride links and rear knuckles. Looks like I have spares now. =P

[Mountain]

Originally Posted by Ryephile

The front ride link inner bushing appears to come in two "shapes", the FE2/3/A, and FE4 "big rubber". Given the part numbers are different between the FE2/3 and FEA links, the durometers are likely different.

Apart from that, it appears the only difference with this FEA kit vs. FE4 is the rear knuckles, which are also different part numbers, and I just looked at my factory FE4 knuckles, the outer LCA is indeed a rubber bushing, not a spherical that's in the FEA knuckles. The front "rear" link and the rear trailing links share part numbers between FE4 and FEA.

Since you're coming from FE3 suspension, this kit is exactly tailored for you. For me, the only improvements appear to be the front ride links and rear knuckles. Looks like I have spares now. =P

Thanks for sharing all this, btw. Many times, there are other "things" that change with vehicle varients that isn't publicized. It's usually hard to get the real low-down and/or takes a while until people really mess with the cars. So, much appreciated!

If you want to sell those extra parts... im in Michigan

[Ryephile]

Originally Posted by Mountain

Thanks for sharing all this, btw. Many times, there are other "things" that change with vehicle varients that isn't publicized. It's usually hard to get the real low-down and/or takes a while until people really mess with the cars. So, much appreciated!

If you want to sell those extra parts... im in Michigan

Glad to help. I'm keeping the extra links, I'll put them on when my stock bushings wear out.

Here are the part numbers for the ZL1 1LE aka FEA suspension differences (ignoring the sway bars and DSSV's)
*Rear Knuckles: 84258571 & 84258572
*Front Ride Links: 84051643 & 84051644

The other control links are shared with the FE4 suspension, but if you want that info too:
*Front Handling Links: 23317367 & 23317368
*Rear Upper Trailing Links: 84059622, same right and left
*Rear Lower Trailing Links: 84048678, same right and left

[Ryephile]

Reading through the "I've cooked the magic" thread, I just want to add this little nugget I wrote a while ago. Sometimes I read something I wrote a while later and go "woah, *I* wrote that? I'm going to steal that!"

Originally Posted by Ryephile

Raybestos' chart is worthless, throw it out and don't look at it again.

Like Sean said, use whatever pad works for you. X25's explanation might be too introspective for some, personally I get what he's saying and agree. 9 times out of 10 when you give someone a pad that has super high mu, they use it the same amount of *time* as a low-mu pad, not to achieve the same speed delta. This is classic over-braking, using them more than necessary.

Example: when I swapped from Power Stop Track Day to ST-43's, the datalogging was showing about 1/4g greater decel rate. As such, the ST-43's need less distance to achieve the same speed delta. Going from 141 down to 62 MPH needed much less distance since the pads support quicker deceleration. As such my braking point had to be much closer towards my turn-in point. The total heat dissipation (Work) is the same, just with more Force over less distance. RXtacy mentioned that deeper braking does mean higher speed at the brake point. This is true but it's not very significant most of the time, a MPH or two. It's in the noise for most drivers that aren't aware of their corner entry speed.

I see a lot of drivers that have it programmed they have to stop from point A to point B and have no idea what their corner entry speed is. That's bad. Give them a high-mu pad and they'll over-brake every time. They're focusing on a fixed distance, and now we've added more braking force. For the driver that can't or won't adapt their distance, you have to adjust the pad to their distance. This is where lower mu pad like the stock Ferodo's will mask a brake control problem. All this can be fixed with some car control practice. You have to focus on the corner entry speed first, forget the braking. Once you figure out the maximum corner entry speed, then you have to program that into your head. From there you have to back-calculate how much distance you need to brake with maximum force on the straight to achieve that speed at the turn-in point. Only then can you start connecting sections together.

All that is covered in Ross Bentley's book. The tough part is having the discipline to apply it to yourself.

[carguy55]

good info here, subed

[Ryephile]

Thanks carguy55!

A bit of an update. I got my new track wheels and tires mounted today. I went with MRR's M716, which are the ZL1 1LE replica's, but still flow-forged with JWL and VIA certifications. 19x10.5" et14 front and 19x11" et36 rear. All 4 corners got the Goodyear Supercar 3R tire in 305/30-19. FYI the front wheels are 26.5 pounds and the rears are 24.5 pounds. Pretty good for how huge they are.

2018 1LE updates by Ryephile, on Flickr

2018 1LE updates by Ryephile, on Flickr

To cope with the extra grip, I definitely need to address the dynamic camber loss problem as seen on the Supercar 3 front tire wear. After getting some good stabilizer bar rate info from member jwisjw, I opted for the Hotchkis adjustable front bar and the BMR adjustable rear bar. This combo let's me use the soft/medium/hard options on both front and rear to make the stabilizer rates roughly 12%, 30%, and 50% stiffer than FE4 stabilizer bars. This will keep the neutral handling balance of the 1LE intact but with higher dynamic wheel rate and less body roll to compliment the grippier tire.

The final bit for now is with the help of 825moto, I picked up a set of take-off ZL1 brakes, front and rear calipers and rotors. They only have 2500 miles on them. The added 20mm of rotor diameter along with the swept area will be good for brake torque, but also the greater mass of the system will help mitigate the very high front caliper temps I was getting with the SS 1LE setup.

2018 1LE updates by Ryephile, on Flickr

It's still very much brrr winter here in the Mitten, so it'll be a bit before it's all installed. I'm waiting on fresh new brake hoses to arrive from GM, always a smart idea when working on safety-critical stuff.

[carguy55]

Looks like a great setup. Can you run those 19x10.5" MMR M716 & 30/30ZR19 up front on a stock 1LE with the recommended track alignment or will they rub? Wow, the 3R specs are nuts, wonder how long they will last on track. All the new guys just getting started really appreciate you guys sharing the info and experience so we don't have to learn it the hard way

[Ryephile]

Originally Posted by carguy55

Looks like a great setup. Can you run those 19x10.5" MMR M716 & 30/30ZR19 up front on a stock 1LE with the recommended track alignment or will they rub? Wow, the 3R specs are nuts, wonder how long they will last on track. All the new guys just getting started really appreciate you guys sharing the info and experience so we don't have to learn it the hard way

Thanks. The ZL1 1LE guys are finding they last about 4 track "days", which seems about right. We'll see as the year goes on and we all get more data points.

As for fitment, I'm going to go with NO, you need camber plates to make these clear with a track alignment of at least -2.5 deg camber.

Since it was above freezing out today I did a test fitment, this is what the strut looks like after a salty Michigan winter, Moreno camber plates maxed out inboard and the knuckles pulled back for -2.6 deg camber.

IMG_3904.jpg by Ryephile, on Flickr

There's clearance, but that's because the camber plates create about an inch of room.

Also something interesting. These Supercar 3R's are very clearly a dual compound carcass. You can see the compound color difference between the sidewall and the tread. They also have a significantly different gumminess. The tread compound is much harder and will obviously need some heat to get sticky, just like a Hoosier R7.

IMG_3905.jpg by Ryephile, on Flickr

Here are some fitment shots of the front. Even with good camber they still protrude a bit. The clag will be everywhere.

IMG_3907.jpg by Ryephile, on Flickr

IMG_3909.jpg by Ryephile, on Flickr

IMG_3910.jpg by Ryephile, on Flickr

Ok, the winter tires are back on and the S3R's are back in the basement until winter is over.

The good news is my ZL1 brake hoses shipped, so when the weather breaks it'll be brake and swaybar time.

[carguy55]

Have you done anything or planning on doing anything to improve front brake cooling, like brake hose or the SS track brake duct kit? I was think of getting the kit it's only $16

[Ryephile]

Originally Posted by carguy55

Have you done anything or planning on doing anything to improve front brake cooling, like brake hose or the SS track brake duct kit? I was think of getting the kit it's only $16

Scroll back up to the picture of the ZL1 brakes. That's a big part of the thermal fix. I also have the SS "track" deflectors on the shelf, I'll use them just to get some comparison to the normal deflectors. The ZL1 only comes with the normal deflectors, so given I'm missing 200 HP, I shouldn't need the SS track deflectors with the ZL1 brakes.

[carguy55]

Originally Posted by Ryephile

Scroll back up to the picture of the ZL1 brakes. That's a big part of the thermal fix. I also have the SS "track" deflectors on the shelf, I'll use them just to get some comparison to the normal deflectors. The ZL1 only comes with the normal deflectors, so given I'm missing 200 HP, I shouldn't need the SS track deflectors with the ZL1 brakes.

[Ryephile]

Finally Michigan has thankfully received a few days of spring!

I took the opportunity this weekend to:
*Swap in the take-off ZL1 brakes
*replace a winter-damaged aero pan, and do a general cleaning underneath
*replace the Moreno strut mount bearing and carrier
*Swap the anti-roll bars with Hotchkis adjustable front and BMR adjustable rear items
*OEM air filter change, and Dexos 2 oil change for track season.

I measured the difference between the FE4 and aftermarket anti-roll bars. For sure the FE4 bars are only incrementally smaller than the Hotchkis front and BMR rear bars. One thing I found curious is how both aftermarket bars have significantly longer torque arm lengths, effectively softening the bar rate and relying on their diameter and wall thickness to make up the difference. Locating the drop-link on the BMR rear bars' softest hole requires grinding the casting nub off the knuckle to clearance the drop-link to the knuckle, otherwise it would bind and likely bend the drop-link. If the torque arm length was closer to stock this wouldn't be a problem. Classic poorly engineered aftermarket. As a baseline I'm starting with the front and rear bars on the medium setting. This puts the roll couple stiffness at about 30% more than the FE4 bars, making it a "full step" stiffer again, given the FE4 bars are roughly 30% stiffer than FE3 bars, though the FE3 bars bias towards understeer, whereas I've kept the balance between FE4 and this aftermarket combination the same. For comparison, at least going off advertised numbers, the BMR front bars are way too stiff, and the Hotchkis rear bar is way too soft.

Stock FE4 front bar, 30x8mm:
Camaro April 2018 updates by Ryephile, on Flickr

Camaro April 2018 updates by Ryephile, on Flickr

Front bar comparison:
Untitled by Ryephile, on Flickr

Hotchkis front bar, 32x12mm, relies on wall thickness over diameter for added stiffness:
Camaro April 2018 updates by Ryephile, on Flickr

Camaro April 2018 updates by Ryephile, on Flickr

********************

Stock FE4 rear bar, 27x8.7mm:
Camaro April 2018 updates by Ryephile, on Flickr

Camaro April 2018 updates by Ryephile, on Flickr

Rear bar comparison:
Untitled by Ryephile, on Flickr

Camaro April 2018 updates by Ryephile, on Flickr

BMR adjustable rear bar, same diameter as the Hotchkis front but thinner wall, 32x9.8mm, relies on diameter more than wall thickness for added stiffness:
Camaro April 2018 updates by Ryephile, on Flickr

Camaro April 2018 updates by Ryephile, on Flickr



The ZL1 brakes, however, are 100% plug-n-play, as long as you have the right pads, backing plates, bolts, and hoses. 20mm more front and 27mm more rear diameter and 2mm more thickness front and rear. Larger pad area front and rear, and the front calipers are significantly larger compared to the SS 1LE brakes, yet in the hand they feel the same weight, very light without the pads. I'm expecting this setup to run cooler for improved pad, rotor, and caliper seal longevity. For the street I have PowerStop Z26's in size 1835 front and 1053 rear, a perfect match for the larger ZL1 pads over the SS 1LE pads. Curiously, the ZL1 rear hydraulic hoses appear identical to the SS rear hoses, however their part numbers are different. I'm not sure why, but just to be complete I put new ZL1 hoses to match. For sure up front the hoses are different as the caliper hose mount is different.

Camaro April 2018 updates by Ryephile, on Flickr

Camaro April 2018 updates by Ryephile, on Flickr

Camaro April 2018 updates by Ryephile, on Flickr

Camaro April 2018 updates by Ryephile, on Flickr


No more red brakes! I kind of like the non-contrast now, more subtle.
Camaro April 2018 updates by Ryephile, on Flickr

I was still running the original Moreno camber plates. After a loooong winter I swapped out the bearing and the updated stronger carrier, however my original carriers were still intact. For sure the assemblies took a beating with the salty Michigan winter, the platings are rough looking and the included mild steel bearing was quite rusted. I swapped in an FK FKSSX12T stainless version, which incidentally is rated for axial loads whereas FK doesn't rate the mild steel as such. Even so, I've coated the hardware with good-ole Bel-Ray Super Clean, heh heh

Max plate camber, dialed back with knuckles for maximum tire clearance:
Untitled by Ryephile, on Flickr

...and directly from the top, "up" is aft. This shows the slightly added caster, about 0.6° worth:
Untitled by Ryephile, on Flickr


Next track day is Memorial Day weekend at Grattan!

[Ryephile]

Oh! So how does it drive?

The ZL1 brakes feel very similar to the SS 1LE in terms of pedal feel, stiffness, and travel. This makes sense in my head as Brembo & GM changed the piston bore sizing along with the rotor diameters. After the pads bed a bit, it seems the same g-decel requires slightly less pressure. I'll put on some temp stickers before the track weekend and check the peak temps and report back then.

The anti-roll bars, however, are more nuanced. Since GM chooses the [IMO] unorthodox method of using the ARB bushings for secondary spring rate, the ride comfort now is marginally improved, yet the roll stiffness is nicely increased. Weight transitions are a step quicker, much like going from SS to SS 1LE, but still reasonable [for me] for an everyday drive. If you thought the transition from SS to SS 1LE really woke up the response, this is that once again from the SS 1LE. Of course, bump firmness over asymmetrical bumps is increased, as expected from greater roll couple. Overall however it's not as dramatic as I was fearing, so I'm pleased I haven't ruined the car.

[RUQWIKR]

FYI, rear hoses are the same, J6M (SS 1LE) to J6H (ZL1) as you mentioned, but the front flex hoses must be changed as you pointed out. Can't wait to see your on track thoughts.