The main issue is not having a ***baseline*** from which to judge effectiveness of mods. That's critical to judge effectiveness of each mod on the car's performance.

One can spend tons of $ without making much difference and even making things worse vs better (been there done it). Then things become complicated in a hurry, while your wallet gets thinner and new parts get sold off at 50 cents on a dollar :)

Frankly, you could put a red stripe on a hood and go a second faster. In other words, a driver putting a really good lap together and gaining time with mods not playing any role in the outcome. So, there is that to consider, especially if you cant reliably FEEL and hence judge each mod.

Going forward, you'll have a faster car due to a bigger blower and slightly different weight balance (I assume).
This will bring new challenges of faster speeds from which to start corner entries, etc. Albeit on your track this may not matter as much, due to its config.

PS Note that GM recommends 2.5F and 2.0R for ZLE. So not surprised they gave ya this rear camber if you asked for ZLE values, albeit i think most ZLE owners run a higher F camber. Bottom line, i would judge its effectiveness based on tire wear and since you haven't commented on this subject per se, i assume it was alright?

spl parts just announced they will be doing a black friday sale 20% off if anybody wants to grab some!

Good question, I have no idea, But if I had to guess I would think that changing one thing would generally mean changing something else to keep everything in balance. But I can’t prove that at all.

Yes there’s definitely trust that SPL knows what they are doing but I don’t think it’s a far-fetched assumption either.

They also said that their tension rods would give me the ability to increase caster, independently of camber, to somewhere between 8.5 And 9.5 which is what they claim a lot of guys tracking the Camaro are at. Apparently without this product the caster is tied to the camber which is why I am now at 7.6 up from my original 6.9 because I’ve increased the camber to -2.5

Excellent, Where did you see this? And what dates of the sale for? I don’t see it on their website

Is there a code or something?

i saw it on facebook they said keep posted for more details

That would presume that they sell different control arms depending on how much the car is lowered. Id check with them this is indeed the case, lest you could go too far the other way and create a completely new mess geometry wise.

The arms are apparently adjustable depending on how much the car has been lowered.
He said he would send me and/or my alignment shop the specs on how much adjustment was needed.

I suspected as much.

OH, there's no question changing some things affects others. Ride height and RC are inextricably linked to one another, for example. That's not what I'm questioning. What I question is whether or not the RC needs to be corrected after a Camaro is lowered. I'm not aware of such a need, and Chevy obviously doesn't see one. That doesn't mean it wouldn't be a good idea. I'm just saying that we don't know.

Well, let's unpack this a bit. Caster isn't adjustable on a stock Camaro at all. At least some camber plates allow caster adjustability, like the Vorshlag units. But the two are independently adjustable. One can limit the other: for example at max camber on the plates you probably have to give up some caster, and vice versa. But within those limits you can absolutely set whatever caster and camber you want, independent from one another. I don't know what caster range the Vorshlag plates give you with no other mods: you might be able to get the 8.5-9.5 you want just from those.

Using the stock adjustment, I don't see how setting camber using the factory adjustment could change caster. That doesn't really make sense. On my 1LE, going from the as-delivered -1.4/-0.9 (left/right) camber to -2.7 on both sides using the stock camber adjustment didn't change my caster one single bit. It read 7.6 and 7.3 before and after the camber change. That's what we'd expect.

Also, it's not clear that normal alignment machines can accurately read caster or steering axis inclination because there is no single pivot point defined by a single lower ball joint. Instead, there are two ball joints (one for each link) and a virtual pivot point defined by their instant center. But the problem is that as the steering is turned, that virtual pivot point moves...a lot. We could define static caster using the virtual pivot point. However, an alignment machine infers caster from the change in camber as the steering is cycled through its range, and that would not be accurate for our cars because that pivot point is moving.

This all boils down to: I'd be interested to know the basis for measuring the caster that track drivers are using. I'd also be interested to know why more is better. Typically, the benefit of extreme caster only matter with extreme steering angles, such as autocross use. More than 7.5 or so is starting to get into the extreme range. So what benefit does 8.5-9.5 give on a road course?

We agree on most of that, but I don't understand why you are saying Chevy does not see the need to adjust anything due to ride height.

Interesting, I'd like to know as well.
I'm quoting what the guy from SPL said, so I can't comment on whether or not he is right. My track has 19 turns in a 1 minute and 20 second lap so it is corner heavy and technical.

This could all be a waste of money but only one thing is for sure, he definitely wants mine!

Please re read my post #30. "Some guy" telling you that "some track guys" run high caster without understanding just how fast they are in the first place and what other mods they may have in a second place is just plain noise best not to pay attention to.

PS GM sells a lowering kit for a non 1LE SS without any specs re changing caster.

PSS By design, the more caster the less responsive steering, the less responsive car = the more understeer.
No race cars run such high caster, unless they are mid/rear engine cars. To the contrary, they usually run less than our stock caster to make them as responsive as possible.

Ah yes, good point!

And good to know! Thanks

They also offer a rear Toe lockout kit that apparently stops the alignment from getting out of whack and causing premature tire wear

thats the only spl part i have so far but will be getting more in future!

On this I was referring specifically to the spindle height and roll center. Chevy makes a range of ride heights on various trim levels of Camaros, and to my knowledge they don't do anything to correct the changes in RC that occur with the varying ride heights.

Gotchya.

I also forgot they offered lowering kits from factory without roll centre correction.

I will be getting the front lower control arms so that I can increase camber. That’s the only part I’m getting for sure

My pleasure! The rear toe kit is proly worth getting.
Speaking of tire wear: increased caster can cause it, due to delayed responses (on the front of course). Cheers!

I have Vorshlag camber plates and run -3* in the front. There are two caster settings on the plates, Stock (7.2* measured on mine) and more(measured 9.2* on my car). so it seems that it's a 2* difference.

The plates make sense for those that cant get enough camber from stock bolts. But, i could get 2.9 out of mine, yet prefer 2.6 for tire wear. Even at that setting they cord first on the inside. Maybe slicks would need a bit more, but i dont run them.

Just curious: you will be getting more parts for WHAT purpose exactly?

Everybody wants our money. All the time. And especially if they sense we may not clearly understand causes and effects :)

What exactly are you trying to fix handling wise? You knocked off a tremendous 3 seconds of your laptime with stickier tires and improved driving alone. Given your track config, i would not do anything that - even remotely:
1) reduces responsiveness of the car
2) increases tire wear

Remember, fix has to be based on what a driver feels, not what some guy tells you, that sells parts. I suspect if he sold shocks he would insist you swap those as well, to match the springs. Etc, etc. If you start listening to others vs yourself, the list will be infinite and your car at an ever changing state of flux. And eventually you may start taking parts out, because it doesnt feel right anymore.

If you want more camber, just get camber plates! Those and rear toe lock out make sense. However, if ya run 2.5 and 2.0, adjust up based on YOUR tire wear and do it in small increments (on the front, obviously) lest you can ruin a pair of F tires in a day (ive seen it done first hand). More is not always better. It all depends on a venue, driving style, tire, etc. So, thats another thing YOU must pay attention to as a driver and adjust accordingly. Not "some guy" that has never driven your car and/or your track.

Bottom line: it is your wallet. But even if ya have plenty of spare cash burning a hole in it, spend it wisely and spend it on items that will give ya best return on investment.
My cents anyway. Cheers!

GMG, i had mentioned this before: if i were you and since laptimes are your obvious focus, i would seriously consider ZLE DSSV suspension (on sale now, see link).

This would lower your car, give you many benefits of coilovers design and Trans Am tested racing solution from one of the top shelf pro racing houses on the planet. Zero guessing here.

Sure, your DD ride quality would suffer, but then again id imagine tons of ZLEs never see a race track and folks do street those cars successfully.

Not only this, but this would position you perfectly for another future go faster mod: aero (which requires much stiffer springs and shocks to go with them).

For the price of all the parts that you are being recommended to purchase (more or less), you can do a wholesale, complete and proven suspension upgrade designed for the car. Plus position for the future. Food for thought.

https://www.gmperformancemotor.com/parts/84352121.html

Their swaybar links would also be a good purchase

What would they achieve over stock? Thanks!

I’m running 305/19 and will soon be moving to 315 or 335/18s so the added clearance to the strut from camber plates is beneficial. I also use the car primarily for autocross and even at -3* I’m wearing the outside more than the inside of the tire. I check tire temps when I’m at Willow Springs and with the fast, high load corners, -3* comes close to even temps with the Supercar 3 tires.

Well, the whole purpose of adjustable end links is so that you can remove stab bar preload when at rest. The benefit is equal roll resistance when cornering. If you happen to have adjustable coil overs, it also makes corner balancing easier.

Agree. Camber plates make perfect sense if increased camber makes a difference based on a venue/driver. That was my key point as well (over revised lower control arms somehow being a "must have" item).

I too run high load tracks and personally 2.6F works great for me. Having said that, i also run a stock G3 tire.

Cheers!

Ya, we did it on my C5Z and frankly i could not feel any difference, nor my laps improved any, nor my tire wear, but my wallet got lighter :)

Agree re corner balancing, but none of the cars being discussed here have coilovers so it is a moot point.

Cheers!

Thanks! If you dont mind me asking: how much are these?

nice ! you will love them

Krops, you must own shares in every aftermarket company :))

But seriously, can somebody translate SPL statement that eccentric lockouts MUST be accompanied by adjustable lower control arms?

haha nope just support the ones that support me and especially nice usa made products!!


and i have them on my car and i dont have the adjustable lower control arms why would you need both?

Ya id become a cheerleader too if i got free gear. We could become quite a team lol :)

But, seriously, that's what their website says: you MUST have adjustable control arms. Hence my original request for somebody to translate it.

I would think that is a misprint... as you would need adjustable TOE arms to run the eccentric lockout.

some stuff free some stuff discounted it pays to work in the auto industry...


and i think thats a misprint

Exactly. Moreover, in product description for their toe arms plus lockouts this warning is omitted. Hmm...

Right :)

Maybe contact your buds there and ask them to remove it then? Or explain it. Either one...

Maybe shoot them an email and let them know what you found while trying to pick apart their product description.

That is their quote on just the lockout kit. They are talking about you must have adjustable toe links if you use the lockout kit. Agree that control arms isn't the correct term, should be toe links, but the rest of the sentence does talk about adjusting toe. And they are developing a lockout kit for the lower control arm which will require you to get the adjustable upper control arms.