GMHTP's 6-piston CTS-V Setup
04-05-2011, 08:16 PM
#145
04-05-2011, 08:50 PM
#146
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Yes those are options, I was just wondering what the one in the post was. There are some other great options by stillen and coleman as well that can be had for ~$800. A sponsor over on another forum has the custom coleman's for that price and are an amazing piece.
04-05-2011, 09:34 PM
#147
07-26-2011, 02:22 AM
#148
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It's hard to argue with this...
Also, glad to see you've done the swap in the past, I think it is excellent for what we are doing with the car and have no regrets about the current setup. I will say that we are planning to go further but everyone is going to have to wait to find out what happens....
Also, glad to see you've done the swap in the past, I think it is excellent for what we are doing with the car and have no regrets about the current setup. I will say that we are planning to go further but everyone is going to have to wait to find out what happens....
07-26-2011, 09:32 AM
#149
I can absolutely assure you that somehow adapting a 996 brake system onto an F-Body will be demonstrably worse than the OE system (all other factors being equal), as well as downright dangerous. The rear brakes on that Porsche can contribute up to 45% of the overall braking effort since the engine is hanging out back --> NOT gonna work on that 'Bird.
This is not rocket surgery (!), but math, engineering and real-world experience. While we are quite safe in holding the .25% incremental changes for race cars, changing mechanical bias on a street vehicle by more than 6 or 7% is inviting trouble -- unless you are talking about a show car.
You certainly are entitled to your own opinion on this, but the underlying physics behind vehicle dynamics is completely neutral and unforgiving. I've made enough mistakes in my career in this field to understand that fact better than I ever wanted to. And this includes (many years ago when I thought it was no big deal) adding too much front brake torque and actually lengthening stopping distances. You just don't forget stuff like that!
Chris
This is not rocket surgery (!), but math, engineering and real-world experience. While we are quite safe in holding the .25% incremental changes for race cars, changing mechanical bias on a street vehicle by more than 6 or 7% is inviting trouble -- unless you are talking about a show car.
You certainly are entitled to your own opinion on this, but the underlying physics behind vehicle dynamics is completely neutral and unforgiving. I've made enough mistakes in my career in this field to understand that fact better than I ever wanted to. And this includes (many years ago when I thought it was no big deal) adding too much front brake torque and actually lengthening stopping distances. You just don't forget stuff like that!
Chris
You have people that are doing things and actually KNOW and you have people that think they know that are always louder. Why dont you go to the track and see people who actually regularly race their 4th gens and see that most of them are running some aftermarket BBK (maybe GM parts but maybe not).
First the factory **** sucks, second if you run a stock caliper or even a c5 z06 caliper track abuse can spread the caliper and ruin them. Its pretty common.
Second If bias is such a problem then adjust it plain and simple. Your making it out like its impossible, but people do it all the time. BBKs using porsche parts is pretty common among the road course crowd.
You should ask some of the people who actually races this setup.
Lastly given GMs track record with these cars not much they did on these cars is right outside of the motor and trans. I could sit here and make list of know problem areas but we all know how long that is, so why would anyone think that they had the brake bias so right from the factory I bet a little change is probably better anyways.
08-04-2011, 11:19 AM
#151
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So slapping on a set of modified Big Reds, we get a system where the front calipers are down 20.2% in piston area, but the effective radius is increased by approximately 15.9%. This would give a rearward balance shift of around 4.3%, which is closer to ideal given the front-heavy OE bias. It would be sensible to predict the driver would be happy with this shift, made possible by the decrease in front axle torque (while also gaining heat capacity as compared to where that car started off). Add in some aggressive track pads and this hybrid system should slow that car down very well.
08-04-2011, 02:44 PM
#152
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What is wrong here is the assumption that theory is reality, the real world works different and the logic behind this isn't spot on to begin with. Increase rear brake capacity causes lock up and very unpredictable results on Fbodies. Stock brakes barely meet capacity of the system and most road racers have altered the suspension greatly to where the stock system can no longer meet capacity therefore better front brakes are necessary; lets not even talk about how quickly they fade. I can guarantee the stopping is greatly improved! I have the 4 piston's on the front with the C4 stock rear brakes and the stopping is unbelievable. I have virtually no fade and the bias is perfect. I have a completely altered and custom suspension on the entire car geared for road courses and these brakes with proper tires barely lock up the tires when they are hot and the brakes are at optimum operating temp. Some can choose not to do this and that the setup is a bad idea, but that is their choice. My choice is based on results, which this setup delivers and if you haven't actually done it and tried it for yourself, you can't really knock it. Theory is great, but its called "theory" for a reason.
08-04-2011, 05:58 PM
#153
What is wrong here is the assumption that theory is reality, the real world works different and the logic behind this isn't spot on to begin with. Increase rear brake capacity causes lock up and very unpredictable results on Fbodies. Stock brakes barely meet capacity of the system and most road racers have altered the suspension greatly to where the stock system can no longer meet capacity therefore better front brakes are necessary; lets not even talk about how quickly they fade. I can guarantee the stopping is greatly improved! I have the 4 piston's on the front with the C4 stock rear brakes and the stopping is unbelievable. I have virtually no fade and the bias is perfect. I have a completely altered and custom suspension on the entire car geared for road courses and these brakes with proper tires barely lock up the tires when they are hot and the brakes are at optimum operating temp. Some can choose not to do this and that the setup is a bad idea, but that is their choice. My choice is based on results, which this setup delivers and if you haven't actually done it and tried it for yourself, you can't really knock it. Theory is great, but its called "theory" for a reason.
Chris
08-05-2011, 09:08 AM
#154
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In my experience (20+ years of it), theory and practice are generally very closely related. This is just plain ol' physics and vehicle dynamics. What happens with major suspension modifications is that often weight transfer characteristics are changed, sometimes radically. This means that the change in brake bias that was designed for a vehicle closer to stock is no longer valid for the modified car. This does not mean that the theory was wrong, but the premises were. A qualified suspension engineer can calculate the changes required and implement those changes before the modified car ever hits the track. This is what we did in NASCAR and Indycars when the testings bans started, as we could not afford to waste time at the track dialing in these sorts of basics when we needed to be way more efficient with the little time we had. But I agree with you -- for the average enthusiast, trial and error is the more realistic course of action. Let's just be sure it is done on the track and not on the highway!!
Chris
Chris
04-26-2014, 12:18 PM
#155
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Sorry to resurrect but in the end what ended up being the actual consensus by guys that actually road race these cars...4 piston CTS-V vs 6 piston CTS-V vs this is a purely aesthetic mod not fit for HPDE/track use??
04-26-2014, 11:34 PM
#156
What was the reason GMHTP swapped the CTS-V caliper to a Baer caliper? In this thread, BMR said there were issues with the 6-Piston CTS-V caliper and they switched to Baer 6S and maybe even back to the 4-pot CTS-V calipers: https://ls1tech.com/forums/multimedi...ti-killer.html
Any insight into what actually worked best? 4-pot or 6-pot Brembos or 6-pot Baer?
Any insight into what actually worked best? 4-pot or 6-pot Brembos or 6-pot Baer?
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Flielow (03-30-2020)
04-27-2014, 10:20 AM
#158
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I think the whole reason why they went with baer was to get a matching rear setup. so they got the baer front and rear bbk. but now they were having to much rear breaking, dont know if they adjusted it or not though.
04-27-2014, 01:54 PM
#159
Not sure how fair of a review I can provide Nate. Though the car stops on a dime with ten cents change...I dont really beat this thing around the track like "killer" does. As you know, I also have a hydroboost which REALLY adds to the stopping power/ability. Unfortunately, doing both at the same time, I dont have an A-B comparison.
