Topic: C6 Z06 Brakes on a '7 GXP

[starkmaster03]

Tire size is 255/45/18; a tad larger than the stock 245/45/18.

Chad - did you get the speed sensor issue situated yet ?

No, not yet.  Been long days and weekends with work.  I was just able to get the car back off the ground.  When do you want me to bring these rims back to you?

[POS VETT]

I actually have no use for them at the moment; nothing in the near future.  Sometime before the year end is good but it's not mandatory.

Are you getting a set of Vossen or are you going with something like CCW ?

[starkmaster03]

I actually have no use for them at the moment; nothing in the near future.  Sometime before the year end is good but it's not mandatory.

Are you getting a set of Vossen or are you going with something like CCW ?

I'm thinking of going with some replica 09 ZR1's unless I can find some originals.  I really would like some CCW's 555's but can justify that price.  The used CCW's on CR are nice but once again I'm looking to buy two sets of wheels and tires.

[starkmaster03]

Got any side-by-side pics of the C6 hubs next to the Kappa hubs?  Curious how much difference there is dimension-wise there.

Ask and you shall receive.  Obviously the rusted hub is the Solstice and the new is the Vette hub.

[2kwk4u]

Thanks, starkmaster03.  You're the man!  So if I gather all of this correctly, 3mm of your wheels sticking out can be contributed to the hub, 15mm to the offset, and 19mm (half of the wheel width difference - .75" * 25.4mm/1inch) can be contributed to the wider wheels.  Meaning overall the outer bead of the wheels protrude 37mm more than stock.  Does that about sum it up?

Not meant as criticism whatsoever... just trying to understand.  I'm considering dumping a fair amount into wheels that are 18x8.5 ET35 (and 5x112 mm PCD) and sending them off for widening (and possibly re-drilling - and then possibly black chrome).  Trying to get a sense of whether or not that will work.

[POS VETT]

He forgot to mention that there are hub spacers.  The front ones are 1/2" thick and the rear ones are 1/4" thick.

[2kwk4u]

Were the spacers necessary for caliper clearance, with these being Z06 brakes?  Or were they needed for clearance given the wider wheel (and/or tire) combo?

[POS VETT]

I'm going to let Chad explain it.

[starkmaster03]

Were the spacers necessary for caliper clearance, with these being Z06 brakes?  Or were they needed for clearance given the wider wheel (and/or tire) combo?

Tom is right.  I spaced the front hubs out a half inch and the rears a quarter inch.  I didn't want to cut the dept of the stock knuckle down to make up for the adapter and offset of the calipers.  I decided to make hub spacers so that the hubs remain stock.  I didn't want to run long studs and wheel spacers behind the rotors.  Here are a few pictures. I made the fronts out of aluminum and the rears out of steel.

[starkmaster03]

Here you can see that the holes are no were close to lining up, so adapter plates had to be made.

[2kwk4u]

OK, so given all of that, we're looking at 37mm more protrusion (summarized in my second to last post) plus an additional 1/4" at the rear and 1/2" at the front.  Totaling 43.35mm in the rear and 49.7mm at the front.  Is my math correct?

[starkmaster03]

OK, so given all of that, we're looking at 37mm more protrusion (summarized in my second to last post) plus an additional 1/4" at the rear and 1/2" at the front.  Totaling 43.35mm in the rear and 49.7mm at the front.  Is my math correct?

That looks right but I'm not familiar with the offset calculations that you have made.

[POS VETT]

Well, there is also a difference in rotor hat thicknesses.

[elff]

How much does all of this stuff affect the weight?

At this point, I would think all of this is heavier than the stock kappa parts.

[starkmaster03]

How much does all of this stuff affect the weight?

At this point, I would think all of this is heavier than the stock kappa parts.

I didn't check the rotors but all the Z06 calipers were right about 50 pounds loaded with pads.

[elff]

Just to confirm
That is
4 Calipers = 50lbs
So 50/4 = 12.5lbs caliper

[TomatoSoup]

Wow.  That seems awfully heavy.  Not sure what the OEM calipers weigh, but much less than that (I hope).  Big increase on unsprung weight?

Interesting... whenever these discussions come up about whether it's worth it to get bigger brakes/better for racing/less fade/bling etc.  Noone talks about unsprung weight. Hmm.

(Please note:  not knocking the OP here.  I think it's great that folks are doing these mods - for all our benefits!)

[Gentleman Jack]

Tomato soup

Why do you have to be so negative all the time?  The guy wants different wheels on his car.  He doesn't care about the added 19.86 pounds of unsprung weight he added.  It's not like he is racing the car or trying to save as much fuel as possible, he just wants to put some giant ass Vette wheels on his Solstice!  You of all people should appreciate that sometimes you do things just to see if they can be done (boost gauge, mirror, crazy electrical stuff no one understands but everyone is amazed by). I can't believe anyone would even take this rant seriously, or read the whole thing for that matter.

Take it easy on the guy.  Jeeze.

GJ

[TomatoSoup]

Tomato soup

Why do you have to be so negative all the time? [...]
Take it easy on the guy.  Jeeze.

GJ

Pppptptptptphtthth...

... and your mother wears combat boots!  Yeah!  (Whatever that means.)

[2kwk4u]

Well, there is also a difference in rotor hat thicknesses.

Touché.  I guess that's what I get for being nit-picky.  I figured rotor hat thickness to be negligible.  Are the Z rotor hats that much thicker than Kappa rolling stock?

[starkmaster03]

Wow.  That seems awfully heavy.  Not sure what the OEM calipers weigh, but much less than that (I hope).  Big increase on unsprung weight?

Interesting... whenever these discussions come up about whether it's worth it to get bigger brakes/better for racing/less fade/bling etc.  Noone talks about unsprung weight. Hmm.

(Please note:  not knocking the OP here.  I think it's great that folks are doing these mods - for all our benefits!)

I actually do race it at autox and track rentals but I'm not trying to be the most competitive.  What I was going for is the fact that I saw the Vette hubs fit pretty easily on another site.  I thought that I could then get the wheels that I wanted but not a fan of redrilling rotors each time.  I know that I could get C6 Z06 brakes to work on my Trans Am that I also race so I went ahead and bought them to see if I could get it all to work on the Sol.  If it didn't work out I would simply put them on the TA.  Yes there will be more unsprung weight, that is normally the case when going with a BBK.  Once again I'm not trying to be the most competitive but I just want everything to bolt up.  Yes there is the bling factor that the brakes will look at home behind some Vette wheels as well.  I figure that I can run some street/strip pads and instead of full on race pads and have the same braking power.  I can also easily find anything that needs replaced for decent price.

[wspohn]

Tomato soup

Why do you have to be so negative all the time? 

I didn't think he was being negative.  In fact he said he specifically wasn't knocking the original poster.

Face it - our stock brakes are perfectly adequate for any conceivable street use as well as much competition use provided you make a sensible choice of pad material, and there is no performance based reason to go to big brakes, so when someone does this sort of mod, it is obvious from the git go that it is done because he wants bragging rights, likes the appearance, or is just a crazy guy that gets satisfaction from modifying for its own sake (I've certainly done the latter).  So there's no point in arguing about that and I don't think TS was getting on his case for doing a mod that might negatively affect handling.

I just like watching mod threads, whether or not I would ever do the particular mod, just because I am a gear head and you never know what bit of info might be useful some day. I always read magazines like Hot Rod when I was racing British cars even though the other drivers thought it was a waste of time, because I found all sorts of useful technical hints there.

The OP is obviously enjoying himself and I (and I suspect TS as well) am enjoying the technical aspects of the thread, even though I would never do this specific mod.

Edit to note that while I was posting, the OP posted a message saying exactly what I had about the mod. Very sensible - thanks for the info.

[starkmaster03]

Touché.  I guess that's what I get for being nit-picky.  I figured rotor hat thickness to be negligible.  Are the Z rotor hats that much thicker than Kappa rolling stock?

The z rotors hat are thicker.  To what extent I'm not exactly sure because I couldn't get my micrometer to fit in to measure it accurately.

[elff]

Interesting... whenever these discussions come up about whether it's worth it to get bigger brakes/better for racing/less fade/bling etc.  Noone talks about unsprung weight. Hmm.

I do.   

My Wilwood Front Brake system is 11lbs lighter than stock per front side.
My front OZ Ultraleggura's are 11lbs lighter than the stock rims.
My Front tires are 4 lbs lighter than the stock goodyears
So I have shed 52 lbs of unsprung weight in the front of my car and 30lbs of rotating weight. 


My Rear Wilwood brakes are the same weight as stock, but larger with larger rotors. So Bigger but same weight.
My Rear wheels are 10lbs lighter than the stock rims and that is rotating weight. 
My Rear tires are 1 lb lighter [Which is amazing because they are 275s!!]
So I shed 22 lbs of unsprung weight in the rear and this is all rotating weight

And last and very important,  the tires match the above weight savings with better traction. 

I consider the upgrade worth ever penny and my car brakes better than it did with the stock components[Tires included in this statement] and now, I have a system that can maintain this level of braking under repeated usage.



I love this thread.   starkmaster03 has some serious DIY skills and it's been fun watching.  It makes the petrol head in me very happy

[Gentleman Jack]

Tomato soup

Why do you have to be so negative all the time?  .........    I can't believe anyone would even take this rant seriously, or read the whole thing for that matter.

Take it easy on the guy.  Jeeze.

GJ