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OK.

The girodisc FRONT rotors just arrived. They weigh 28 pounds (see pic below) STOCK OEM ZL1 rotor weighs 32.8 pounds a 4.8 pounds difference. (2nd pic)

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Since I am running 8MM spacers on my APEX 18 x 11 wheels when I run my RT660 315-30-18 tires I went ahead and ordered some 1/3 inch LONGER wheel studs for the front hubs.

I would have preferred ARP but no one has the damn things in stock so I got these:

https://www.ebay.com/itm/264715680249

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A few posts up you will see where I installed a VELOSSA Tech Big Mouth Ram Air system. I will have more feedback for you NEXT week after I finish a LAP ATTACK track day at EAGLES CANYON.

My ASS meter tells me that this probably doesnt make much difference at SLOWER speeds but I definitely FEELS like the car is pulling a little harder at the UPPER LIMITS vs NOT using the RAm Air setup.

Since Eagles Canyon has a Half Mile back straight, we will see if the car can MPH a little higher.

For those curious I already had a BIG MOUTH ROTOFAB Air Intake, and the addition of this RAM Air DID not really add any additional intake noise from what I could tell.

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Eagles Canyon CCW Lap Attack event via the www.apexhpde.com boys is THIS saturday 7/9

ok well GIRODISC Front full rotors will be going on along with MUZZY 1/3 inch longer Wheel studs. Vented brake piston kit part number 19207043 and piston boots 19207044 will be going on as well as long as someone gets off their ass and ships the parts to me in time.

New brake fluid WILWOOD EXP 600 Plus will be installed and Oil was already changed to Valvoline 20-50W VR1 Full Synthetic with WIX oil filter.

SLICKS are now BACK on the track wheels instead of the RT660 200TW tires because I am shooting for a 2.02-2.04 lap time. I will be in CLASS 2 Lap Attack Canyon CCW. With temps expected to be in the 100's, I am not sure those times are possible but will see.

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Ok guys I saw a thread on this but I cant find it for some reason but HERE is the situation with ANYTHING that is shipped form the GM factory.

GM uses their own internal shipping method to get the parts to the dealers and there basically is NO WAY to track a shipment that leaves the factory.

Case in point I ordered 19207043 from GMPARTSDIRECT on July 6th. The FIRST thing that is VERY aggravating is that they dont tell you whether or not the part is in inventory at the time of order.

SO............you find out AFTER you have paid for the part that well that part is on national backorder and will have to be shipped from GM. So if you paid for expedited shipping THAT is a waste of money because that only applies to getting the part to YOU from people like GMPARTSDIRECT, ONCE they receive the part from GM to THEIR facility.

ALL you can normally get is that YES the part is in transit from GM and basically it will get there when it gets there but there are NO shipping details other than that.

Now I am suppose to be OK with this I suppose because there are only SIX of this specific part number in the whole damn country and I will at some time in the future get TWO of them.

I am getting TIRED of hearing that COVID has caused all these service issues because that is CONSTANTLY used as an excuse to provide POOR service levels and we all are suppose to be OK with it. NO DOUBT it has made things more difficult. I am NOT going to patiently wait on the phone for 15-20 minutes to then be told I cant do anything for you.

There are a FEW vendors out there that provide their customers EXCELLENT support. The majority unfortunately DO NOT.

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Well boys ,

Track day yesterday and outside temerature was 105 degrees. That made it too hot really to get the 2.02 - 2.04 times I wanted but I did manage a 2.07 which was good enough for second place to a 2017 corvette that had BIG Aero and was MAYBE 2 inches off the ground LOL

His car was naturally aspirated as well . The heat was taking its biggest toll on my brakes. As I mentioned I was waiting on some caliper parts but they didnt get here on time so I babied the brakes a little bit but they definitely were not as good as they should be.

Just got an email that the brake parts will be here Monday so that will be this weeks project.

[s346k]

gain any speed on the straight from the velossa thing?

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Originally Posted by s346k

gain any speed on the straight from the velossa thing?

Well that's hard to say. The reason being is that I normally brake at the 2 track marker at the end on the straight on Eagles Canyon. YESTERDAY I was having to brake a little sooner at the 3-4 track marker because of some brake issues with the calipers. I was hitting around 135 MPH though which is about the same as when I was braking at the 2 earlier in the year when it was also 10-15 degrees cooler.

So with that being said, I THINK it was good for maybe 1-2 MPH but I cant really absolutely prove that. As MICHAELANGELO said:

PEFECTION IS NO SMALL THING BUT IT IS MADE UP OF SMALL THINGS

So really the Velossa Tech Ram Air is a small thing but probably worth it in the scheme of things especially considering the cost is 169 dollars.

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I know it has been mentioned before in other threads but for those people running the GIRODISC front rotors like Myself , the CORRECT DTC70 Hawk Pad to use is part number HB649U.605. This pad is referred to as a 1405 shape pad. This pad is slightly narrower than the pad you would use on a STOCK ZL1 rotor which is part number HB631U.622 (for STOCK Zl1 rotor).

The overall diameter of BOTH the stock rotor and Girodisc Rotor is roughly 15.35. The GIRODISC rotor however has a larger HAT area so of course that means that the width of the actual braking surface is slightly narrower on the GIRODISC rotors which by the way are DIRECTIONAL unlike the stock rotors.

If you have the REAR Girodisc rotors, then you can use the same brake pads as what you did on the STOCK rotor setup. The pad shape on this one is called 0592. Correct part number for this DTC60 pad is HB194G.570.

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Ok first off, I had always assumed that ZL1 calipers are powdercoated from the FACTORY. The people at www.TOPKOAT.net however informed me that the factory calipers are actually PAINTED. That may be why they discolored so badly since powdercoating is more resistant to heat than paint

SO....I had them powercoat the calipers a color called TIGER Bengal Silver. Thats the color they said closely matches the factory silver color that the ZL1 calipers WERE. I found our AFTER the FACT, that they could have also powdercoated on the ZL1 logo which I would have gone for.

This afternoon we will be installing NEW vented brake pistons, seals and boots. These pistons came originally on the J57 Z06 brake package. So if you order these from GMPARTSDIRECT (part number 19207043), they WILL NOT ship them to you until you confirm that these will indeed fit our cars . It took me THREE days to get them to release my order.

So the VENTED brake pistons with the use of the GIRODISC titanium brake pad shields SHOULD prevent the calipers from discoloring due to EXTREME heat.

I will post pics later on this evening. For those curious, the cost to powdercoat the calipers was roughly 275 dollars. The J57 vented brake pistons with seals was 200 for each caliper . The boots (part number 19207044) are about 25.00 per caliper.

I will post some pics up later this evening

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Here are pics are the freshly powdercoated and rebuilt calipers. Notice in the FIRST pic that the caliper has 3 different size brake pistons. The LARGEST brake piston is nearest the bleed valve, then you see the one in the middle that is smaller and the last one is smaller than the one in the middle.

If you look closely you will see VENT holes at the outermost edge of the piston that makes direct contact with the back of the brake pad when they are in place. This vented piston design is what was used on the J57 brake option on the corvette Z06. A stock ZL1 brake piston DOES NOT have these cooling vents.

Second pic is looking straight down into the caliper and the third pic is the BACK of the caliper.

Overall finish is EXCELLENT and he uses threaded plugs on anything that has threads so that the powdercoating does not seep into those areas.

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UPDATE

When I was at EAGLES Canyon, the car seemed to me like the rear end wanted to move around a bit side to side like the stabilitrack was kicking on and off. So I took it back to DOGOUSE Performance at his shop at Motorsports Ranch in Cresson TX.

I got Adam Poland to test drive the car and he confirmed that SOMETHING definitely was a little off. He runs with ALL the nannies off, which took stabiltrak out of the equation, the car still seemed to have some movement side to side.

We did an alignment check and found then THRUST angle on the rear was a -0.12 degrees . It really should be CLOSE to ZERO. SO....He did alignment adjustments as shown in the file below.

I will use these alignment setting for BOTH street and the track. This alignment was done with my 18" Pirelli Slicks on and with tire pressures at 20 PSI on the front and 19 PSI on the rear.

On the street, I will run these same settings but with MS 4S 305 30 19 wheels and 38 PSI cold at all four corners. Notice there is very little toe IN toe Out.

The only other issue we found was the mapping on the throttle body needs to be MORE linear and I will get AMP to fix that next week. Using the NW 103MM TB currently compared to the PRIOR LT5 TB.

I think what caused the trust angle to get off in the first place was a HARD OFF track incident. Adam reminded me that ANY TIME that happens you should have your alignment rechecked even if it feels that nothing has changed in the way the car drives

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As far as FACTORY produced super cars go, Mercedes has come out with the AMG GT Black Series. The reason I mention this is because we will be attempting to make my LOWLY Camaro SS 1LE with extensive mods but basically full weight competitive if not even QUICKER than the 400K Mercedes around a road course.

This Mercedes factory super car has over 720HP and has a POWERED rear wing that is adjustable and produces over 900 pounds of downforce. It is even QUICKER than a McClaren 765S. Here is an overview of the car.



This car LISTS for over 400K but you have to pay quite a bit more than that to get one.

This car according to Adam Poland whose shop is located at Motorsports Ranch in Cresson Texas STOCK has done laps on the 1.7 course CCW in the 1.14's. To give you some perspective, the quickest Camaro we currently have on the FAST LIST has a time in the HIGH 1.16's.

To get where we need to be with my car we will be messing with Throttle Body control tables so that we can get a more linear relationship of the gas pedal to the throttle body blade opening.

There are two ways to do this. One is to change the ECU programing via a program like HP Tuners or use a system that piggybacks into the EXISTING throttle controller like a VITESSE Throttle controller.

The reason we want to do this is because there is always a built in lag between the time you depress the gas pedal and the time the throttle blades respond. This is called a drive by wire system since there is no mechanical connection between the gas pedal and the throttle body.

Now you dont want this to be too sensitive or the car will be too jerky to drive smoothly. What you want is for the car to SMOOTHLY apply power and NOT to suddenly open the throttle blades with just a slight increase in pedal pressure. The type of sudden increase I am taking about is the equivalent of a boosted car getting in a boost range that spins the tires suddenly while for instance you may be doing a corner out procedure . You want to more directly control the power band of the car in a VERY predictable fashion.

I plan on trying out BOTH ECU programing and the Vitesse Controller which had NINE sensitivity settings in SPORT mode that can be adjusted on the fly. Setting 1-3 are close to stock and Setting 9 is VERY aggressive. We plan on using setting 6-7 since I will be running slicks and should be able to hook up well .

I will post back the results.

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Today AMP updated my throttle position tables so that the throttle blade in the NW103 is more in synch with the accelerator pedal.

On a NW 103 TB for instance there is NO HOLE in the throttle blade and I am running a fairly large CAM so with NO PRESSURE on the accelerator pedal, the throttle blade in the TB is roughly 20% open. Note: On a STOCK CAM at IDLE the throttle blade is about 15% open.usually

For purposes of emissions and fuel economy, the factory tables are set up so that there is some lag usually at anything in the 30% to 80% position on the pedal. So for example at 40% depressed on your accelerator pedal, your throttle body blades may only be 30% open. This is how your typical DRIVE BY WIRE systems work.

The DIRECT effect that this has on road racing is generally at the corner out position where you are exiting corner onto the straight. You want the engine to SMOOTHLY apply the power when you are applying LESS than full pedal pressure so as to not upset the balance of the car. With FACTORY tuning and a decent amount of power, the car CAN BE a little jerky because you DO NOT have a more direct correlation of your pedal to your throttle body blade. Most people refer to this a THROTTLE RESPONSE. Be careful with this because you CAN have TOO MUCH throttle response which makes the car difficult to drive as well.

Generally DRIVE BY WIRE systems have poor throttle response in the 30-80% pedal pressure range. HPTUNERS can be used to fix this issue and thats what AMP did today.

You could also use something like a VITESSE Throttle controller but it is probably BETTER to program the ECM as long as you are not concerned about factory warranty.