Sideways Posted June 10, 2013 Share Posted June 10, 2013 (edited) I see a lot of talk on the forums about how fast someones car does 0-60 or 100, how quickly itll shoot down the 1/4 mile, how much power they were able to put down on what kind of dyno, how many Gs they can hit/hold on a skid pad, and etc.But what about brakes? Brake upgrades come up all the time here- Larger calipers, vented rotors, disc conversions out back, etc. Weve got a lot of options available to us now and a lot of us are experimenting with these options to find whats "better". But I've never seen anyone talk about actual measured results. Id like to see this change, Id like to see us create a source of results to help others dial in their brakes and help establish some benchmarks.Id like to welcome anyone and everyone who has measured their braking distances to share what theyve managed, or to ask others to go out and (SAFELY) find out their own to share with the rest of us. Please include relevant information no matter how trivial. Master cylinder swaps, rotor swaps, caliper swaps, what pads you were using, if you have a proportioning valve or brake bar installed, what tires and their size, etc. I know a lot of this will come down to tires and brake balance, but im extremely curious to see what kind of "balance" were hitting with some of the readily available upgrades/swaps/kits, etc. Again this is just to help us establish some base line benchmarks in hopes that we can help eachother dial in (or down) what kind of braking distances were seeing. Think your brakes are awesome? Come and compare!As a reference- Most sources Im able to track down place a stock early 70s 240z at doing 60-0 in 150 feet. Anyone else care to contribute? Edited June 10, 2013 by Sideways Quote Link to comment Share on other sites More sharing options...
Nigel Posted June 10, 2013 Share Posted June 10, 2013 Great topic! I'd love to see a discussion of this too. With modern cell phones and tablets with built in G sensors, braking force datalogs should be possible too. I'm hoping to run a few tests myself this summer. Nigel Quote Link to comment Share on other sites More sharing options...
CasperIV Posted June 10, 2013 Share Posted June 10, 2013 (edited) The problem is that it is actually quite hard to measure braking distance. I am going to attempt to do so once my car is back from paint and put together, but I remember doing so with my S2000 was a PITA. The problem is that GPS isn't always very accurate on the move for positioning, so calculating from the point brakes are applied to when motion ceases doesn't work very well. Likewise, measuring with static means (stop cones and a measuring tape) is more of a guesstimate as it is very hard to the driver to start applying brakes exactly as they cross the cones. Beyond those issues you then have to be able to really use the brakes at 99% so that you can stop as fast as possible without locking and adding distance. I would be very interested to see what people can get number wise, but I don't believe it will be very definitive without some decent equipment. I personally am looking to setup a cone braking zone while also using a G-Tech Pro and just doing as many tries as I feel it takes to get a good test... but that means A- having a place to do it and B- having a $200+ tool to verify data with. There will also be significant differences in stopping distance due to tire size, composition, pressure, suspension stiffness, and weight distribution. My results may not be overly useful to everyone as I will be doing it with a car that has an SR20DET swap which will change things a bit. Edited June 10, 2013 by CasperIV Quote Link to comment Share on other sites More sharing options...
280zex Posted June 10, 2013 Share Posted June 10, 2013 (edited) I'm willing to contribute!! However I am still waiting for my transmission rebuild. When that is done I'm off to the track!! My car 1976 280Z, turbo 2.9L straight 6, weight with 1/2 tank gas is 2680lbs Brake upgrades are: Toyota 4x4 4 piston calipers up front with non vented rotors and SS lines. Rear disc conversion with 1 piston stanza calipers and non vented 300zx rotors with SS lines. stock brake pads on all 4 corners. Chevy 1 1/8 master cylinder with upgraded hard lines. Stock brake booster. I have an Autometer DPIC g-meter guage installed in my Z. This measures accel, lateral and decal g's along with 0-60, 60-0 times via datalog. I can post up what my findings are. My tires are about used up, AND I will be on a 1/4 drag strip. So my GUESS is that may sqew the information a little as most tracks have a lot of rubber on the surface giving extra traction v.s. regular road surfaces (?). I am very curious about what other Z drivers find out!! Edited June 10, 2013 by 280zex Quote Link to comment Share on other sites More sharing options...
Nigel Posted June 10, 2013 Share Posted June 10, 2013 Brake upgrades are: Toyota 4x4 4 piston calipers up front with non vented rotors and SS lines. Rear disc conversion with 1 piston stanza calipers and non vented 300zx rotors with SS lines. stock brake pads on all 4 corners. Chevy 1 1/8 master cylinder with upgraded hard lines. Stock brake booster. That's a huge master cyclinder for rather small calipers! Have you actually tried it yet? Nigel Quote Link to comment Share on other sites More sharing options...
scott Posted June 10, 2013 Share Posted June 10, 2013 Because there are several factors beside the brake components themselves that affect braking distance, setting up a test with one car and running tests with various brake configurations could separate out some of the variables. The test car could have a base configuration (weight and weight distribution) and set up with wheels (that can fit various brake components) and good tires (so that limits of some brake configurations can be evaluated). Similar brake pads could be used, but there are trade-offs (initial braking distance, fade, rotor wear. Some are better for track use and others for the street) This could be done like component evaluations done in some of the performance car magazines, like intake manifold evaluations or carburetor comparisons done on a base engine. Other factors should be evaluated like brake fade, reliability (this could be harder to evaluate), weight and cost (most are looking for a good balance of features for their braking system). I'd be interested in seeing this. I would like to see how Toyota SW12 calipers with 300ZX vented rotors compare with the stock brakes and with a Wilwood set up, etc. Quote Link to comment Share on other sites More sharing options...
280zex Posted June 10, 2013 Share Posted June 10, 2013 That's a huge master cyclinder for rather small calipers! Have you actually tried it yet? Nigel yes, its been this way for 5+ years now. The chevy master cylinder is for 1/2 ton truck with 4 wheel disc brakes. I also replaced the hard lines with a larger diameter. The setup works well and a heavy foot on the brake pedal will lock up all 4 tires equally. Quote Link to comment Share on other sites More sharing options...
randy 77zt Posted June 10, 2013 Share Posted June 10, 2013 (edited) Before I sold my z I used to run open track days with it.I used to like turn 10 at thunderhill-110 mph into a left hand 90 degree corner typical of a residential neighborhood.You could feel yourself being restrained by the seat belts .The hot track dot slicks(kumho v700) gave me traction that wasnt available on the street with cold street tires and inconsistant surface.I put some huge (345/35-17) rear tires and a disc brake kit on the rear of a fox body mustang for a friend.The huge rear tires got less grip under braking than the smaller tires that were on the car before the swap-the only way the huge tires would work would be under a road course condition where they were heated by use.Basically for looks only.I think a fair way of measuring a cars braking performance would be to measure g force under braking.I think there is an app for this on i-phones.Under some form of heavy duty use most people will find their brake system has been thrown out of balence (front x rear) by the brake mods they have chosen for their car.It took me 3 years of track days (3 or 4 times a year) to get my car to run with slower classes of trailered in race cars and pull decent lap times.My car could brake very hard on the street.I liked to scare passengers by running down freeway off ramps at 110 mph and pulling about 1g+ coming into a stop light with out any tire squeel.But if you jabbed the pedal or couldnt modulate the braking the car could have swapped ends becuase of too much rear brake bias-car was set up for track days.The brake set up on my car- 280 zx 15/16 master cylinder.4 piston toyota truck calipers.Drlled 84 300 zx rotors in front wih porterfield r4 pads.New brake line ran to the rear with Willwood proportioning valve by the gear shifter.84 300 zx rear rotors with 2 piston Willwood calipers with porterfield r4s pads.Ford motorcraft fluid-good stuff for free from work.The fluid was flushed before each track day.Brakes could be used with out thinking about overheating.My car was heavy-2650 lbs-1977 z with zxt motor and a/c.Stock s30 brakes will overheat and fade -or warp rotors.I did it. Edited June 10, 2013 by randy 77zt Quote Link to comment Share on other sites More sharing options...
NewZed Posted June 10, 2013 Share Posted June 10, 2013 I liked to scare passengers by running down freeway off ramps at 110 mph and pulling about 1g+ coming into a stop light with out any tire squeel.But if you jabbed the pedal or couldnt modulate the braking the car could have swapped ends becuase of too much rear brake bias-car was set up for track days. http://www.liveleak.com/view?i=3c7_1370751956 Quote Link to comment Share on other sites More sharing options...
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