Cool thread!

The link reinforces my belief about the ability of the GM Performance Lowering Kit based on my experience. I need to finish installing the ZL1 1LE kit handling package.....

But it's interesting that the ZL1 1LE Handling & DSSV set up was the worst at 6 seconds. Maybe overload on the tires IDK

As a note for others. I have the Front Handling Link and Ride Link installed. Can't say the the Ride Link did anything, but the Front Handling Link with the spherical bearing seems to have reduced binding as it should. TBO, it feels softer in the front over the standard SS bits.

They put an insane amount of effort into answering the question.

I'm really surprised at all of the results. How the heck is the DSSV setup slower than the lowering kit and the SS 1LE?

I wonder if some of the differences are greater than one might have expected, due to the specific nature of the milford course? Here's some other data which is less scientific/rigorous than the data provided from Al & team in this thread.
C&D's lightning lap at VIR: SS 1LE 2:54.8 vs. V6 1LE 3:04.0 (FE3 suspension). That 10s seconds on a 50% longer course. The tires make probably account for 2.5-3 seconds (extrapolating team's data from Milford), so ignoring the V6/V8 power difference, there is roughly the same absolute margin compared to SS 1LE vs. SS FE3.

Motor Trend had the SS 1LE around Willow springs at 1:20.67. They had a 2SS do a 1:23.15 (magnetic suspension) and a V6 1LE 1:25.19. 1/3 shorter course, but the differences are again smaller.

Regarding comparisons to skidpad/figure 8 numbers, while is it obviously a measurement of handling capabilities, it may not translate perfectly.

The written explanation seems to indicate that the DSSV system might be a bit too stiff for longer, faster, better flowing road courses (in contrast to short, tight Auto-cross circuits)

I saw that, but the question is then why spec it for the ZL1 1LE if it's inferior? That's part of what makes me wonder if Milford is kind of a special case. Surely the DSSV setup is better than the FE4 suspension in usual track situations.

I'm guessing the e-diff accounts for ~.6 seconds. C&D did a test with a Lexus RC F with and without e-diff and had a 1:18.7 vs. 1:19.1 laptime difference.

Because the ZL1 is not an SS. When a car is heavier, it needs a stiffer suspension to be 'right'. Plus, the ZL1 1LE suspension was designed to work in concert with all the aerodynamic downforce that the ZL1 1LE generates. Again, that calls for a stiffer suspension.


The ZL1 1LE suspension is neither inferior nor superior. Its different. It was designed for a different purpose than the SS suspension and is better at different things, but worse at others.



And Milford probably isn't a special case. It was designed explicitly to be a good proxy for a variety of tracks.

Depending on the trim level of SS (eg. SS 1LE), the ZL1 1LE weighs as little as 100lbs more. I don't believe the 100lbs comprehensively changes the suspension requirements. SS models themselves vary by almost that much.

I agree aero, bigger/stickier wheels/tires play some roll, but when they say the rear wing makes 300lbs of downforce at 150mph, the suspension still has to work in other corners. There aren't a lot of 155mph corners out there and the downforce is likely close to half in a 80-100mph corner, let alone a 50.

There's no question that different suspensions are tuned for different purposes. Part of the magic of the DSSV and magnetic shocks vs. conventional dampers is that they can be tuned to behave differently in different situations. I recognize how they've described Milford and I've read that stuff before, but part of me wonders if Milford has some bumpy sections that are not conducive for the DSSV shocks, almost like a general handling course...

Seriously though, did you read that laptime vs. suspension chart and think "just as I would have guessed?" :)

The key takeaway from all this to me is that the suspension system / tire / aero needs to be tuned as a whole to be optimized. You can't just slap on stiff springs or sticky tires and call it a day. I wouldn't be surprised to see a car with lowering springs alone and stock shocks to be slower on the track than the stock car. The ZL1 1LE suspension kit clearly needs the ZL1 1LE spec wheel/tire combo (and probably aero too) to perform well. This is where GM is at a huge advantage compared to most aftermarket companies - they have the engineering resources and budget to really optimize the performance of the suspension kits they are offering. There's exceptions, but most aftermarket companies probably never have their lowering springs or coilovers on track before launching the product for sale.

If GM advertised these lap time improvements with their suspension kit (on the "build and price" website), I think more people would check the box for that option.

That's pretty cool that they took the time to do that. Thank you Camaro team!

My 6th test would have been the Test 5 set up plus the G3 tire to show the difference (or not) with the DSSV's and the SS lowering kit. The 7th test to have run would be a base SS 1LE with DSSV's. My 8th test would have been the SS 1LE with the G3R's / ZL1 1LE tires, and the 9th the SS 1LE with DSSV's with the G3R's...

Looking to buy the lower kit and handling kit, however, I noticed they used Part#84188726 for lowering kit and Part#84242386 for the handling kit.

And on shopchevyparts for the lowering kit they have Part#84203549 and Part#84401188 for the handling kit. Are these the same? Links below. Thanks!

https://www.shopchevyparts.com/perfo...-92294544.html

https://www.shopchevyparts.com/perfo...-92292611.html

This ^

Bravo to the answer on this.

I believe you are correct on both. The new part # on the SS suspension lowering kit is definitely 84203549 (replaced 84188726). A GM rep confirmed this for me as well, though not sure what exactly changed that drove a new part number.

I checked the Chevrolet accessory site and it appears 84401188 replaced 84242386 for the swaybar/link kit.