I came up with yet another idea of using the Traction Control System (TCS) pump thats used on the rear brakes (When rear wheels spin faster than the front) to use when normally braking or in emergency braking. So basically the TCS pump would pump brake fluid to the rear brakes along with you pressing the brakes as well to stop the vehicle faster.
Sadly you can't really tie the TCS pump into the front brakes because that would cause more real world problems. But the newer cars come with this sort of feature I assume but that works with all four wheels I assume as well.
I don't know how many Q45a (Active Suspension) cars came with TCS but they would see the biggest benefit of this idea. And sadly only 1991-1996 Q45's came with TCS so sorry 1990 Q45 people. I have to admit 1990 Q45 owners must be better drivers because of the lack of extra's (electronics).
What do you guys think?
Using the TCS pump to decrease braking distance
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Infinitiguy19
- Posts: 7787
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- Car: 1993 Infiniti Q45 188580 Miles
1994 Infiniti Q45a 240000 Miles
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Q45tech
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- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Re: Using the TCS pump to decrease braking distance
The Q45 ALREADY uses a HIGHER rear brake bias than most conventional vehicles ever buit since it has a viscous differential.
The 54/46 weight bias and the 113.2" wheelbase creates a minimal weight transfer during a panic stop.
95% of braking distance comes as a result of tires anyway. The system was initially designed for soft fast wearing tires [using 400 index tires] will lengthen the stopping distance vs 160.
I would suggest you spend a few weeks studying and deriving the mathematics of the entire braking system you will see if anything that the rear system is overbraking for the typical tires used on Q45.
The 54/46 weight bias and the 113.2" wheelbase creates a minimal weight transfer during a panic stop.
95% of braking distance comes as a result of tires anyway. The system was initially designed for soft fast wearing tires [using 400 index tires] will lengthen the stopping distance vs 160.
I would suggest you spend a few weeks studying and deriving the mathematics of the entire braking system you will see if anything that the rear system is overbraking for the typical tires used on Q45.
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Infinitiguy19
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1994 Infiniti Q45a 240000 Miles
Re: Using the TCS pump to decrease braking distance
I had no idea that the rear differential would help with braking. I wish this idea would help with braking but at the same time its somewhat difficult to implement.
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Q45tech
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1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Re: Using the TCS pump to decrease braking distance
Removing ABS will under expert driver operation reduce straight ahead braking distances, as every ABS cycle increases braking distance.
Easy to measure time and number of ABS cycles to see how BAD TIRES are relative to road. The longer lasting the tires the more the ABS cycles in each stop.
Just be sure you have a time base that resolves things to 1-3 thousandths of a second to get all data.
Fresh brand new ABS relays can give you a foot or two edge on braking distances. At 60 mph = 88 fps thus each 1/100th is 0.88 feet..........cycle time should be 1/6th of a tire revolution in feet.
As a scientific exercise measure /calculate the time it takes for each caliper to let off and resume braking and how that effects the pad and rotor and tires.........even the road is change by a single vehicle braking.......momentarily.
How does camber and body dive affect braking, how do lowering springs increase stopping distance. Hint measure camber gain curve as the body dives 2-3 inches un front.
Easy to measure time and number of ABS cycles to see how BAD TIRES are relative to road. The longer lasting the tires the more the ABS cycles in each stop.
Just be sure you have a time base that resolves things to 1-3 thousandths of a second to get all data.
Fresh brand new ABS relays can give you a foot or two edge on braking distances. At 60 mph = 88 fps thus each 1/100th is 0.88 feet..........cycle time should be 1/6th of a tire revolution in feet.
As a scientific exercise measure /calculate the time it takes for each caliper to let off and resume braking and how that effects the pad and rotor and tires.........even the road is change by a single vehicle braking.......momentarily.
How does camber and body dive affect braking, how do lowering springs increase stopping distance. Hint measure camber gain curve as the body dives 2-3 inches un front.
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djwarner
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2006 350Z - Location: Central Florida
Re: Using the TCS pump to decrease braking distance
Paul,
What makes you think you don't already have the proper balance of braking power front versus rear? Proper design says the front brakes should always lock-up before the rear. If the rear locks up first in any kind of turn, you'll swap ends. I believe the design engineers knew this.
What makes you think you don't already have the proper balance of braking power front versus rear? Proper design says the front brakes should always lock-up before the rear. If the rear locks up first in any kind of turn, you'll swap ends. I believe the design engineers knew this.
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Q45tech
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1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Re: Using the TCS pump to decrease braking distance
With ABS it's all in the software inside ABS computer over and above the ratios set by piston area, fluid pressure divison, and master cylinder.
Published 129 feet [with fast wearing Michelin's] in 1990 was serious stopping power in a 4,000 pound vehicle.
By the way a 1990 300zx took 132 feet to stop the lighter vehicle.
Published 129 feet [with fast wearing Michelin's] in 1990 was serious stopping power in a 4,000 pound vehicle.
By the way a 1990 300zx took 132 feet to stop the lighter vehicle.
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Infinitiguy19
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1994 Infiniti Q45a 240000 Miles
Re: Using the TCS pump to decrease braking distance
Really says something to the people that want 300ZX brakes, Just kidding.Q45tech wrote: By the way a 1990 300zx took 132 feet to stop the lighter vehicle.
DJ: I was just hoping I could improve the G50 (1990-1996) Q45 in someway. But this is not one of them which like I said is sad/ but at the same time I am glad because installing Brake pedal position sensor or switch for this would be a pain.
And thanks for confirming what I had thought Q45Tech about electronic relays. I knew they must wear out so I want to replace EVERY relay in my Q45 to get it back to new. I hope I will see the best change from the new Engine Control Module and Ignition (Spark) relay's!
But that will have to weight for a IOS order as the local dealer (They know who they are) want $15 for the shift indicator light bulb. It didn't burn out but while I am in there I might as well replace it after going through that mess removing those three screws.
Q45Tech I will read up on all your posts that I can find (Google Docs and NICO search) for the Q45 brakes. hell I would make a list of your bests posts but I can't find a single bad one so everyone might as well just search for your posts. I know many will disagree with me on this one.