I'd like to upgrade my Q45's front brakes with 300zx, and then use my Q45 calipers and new redrilled rotors on my 240sx.
First question, who's put 300zx on a Q and how do you like it?
Second question, do i need to swap anything more than the brake lines to pull off these brake swaps?
Most importantly, what can i screw up doing these swaps? ..better than learning the hard way.
Brake Swapping 300zx to Q45 and Q45 to S13
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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: Brake Swapping 300zx to Q45 and Q45 to S13 (dareo)
The oem 300zx calipers and rotors won't be much [if any improvement on the front of a Q] as the 300 rotors are not that much thicker [all the 2mm thickness is in middle air space] or heavier than oem Q rotors: No gain in rotor diameter!
1990 N/A: Aluminum caliper, 280x26mm rotor1990 TT and 1991-1992.5 (all models): Aluminum caliper, 280x30mm rotor1992.5-1996 (all models): Iron caliper, 280x30mm rotor
Q45 280 x 28 mmCaliper cylinder bore = 42.8 mm [1.685] X 2pad 127mm x 56mm x 9.5 mm thickMaster cylinder bore 17/16 or 27mmSplit point 569 psi x 0.4 reducing ratio
1990 N/A: Aluminum caliper, 280x26mm rotor1990 TT and 1991-1992.5 (all models): Aluminum caliper, 280x30mm rotor1992.5-1996 (all models): Iron caliper, 280x30mm rotor
Q45 280 x 28 mmCaliper cylinder bore = 42.8 mm [1.685] X 2pad 127mm x 56mm x 9.5 mm thickMaster cylinder bore 17/16 or 27mmSplit point 569 psi x 0.4 reducing ratio
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Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- 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: (dareo)
What is the temperature of rotors/calipers [as measured with IR temp gun] at which [immediately after] you notice the fade [by having to push the brake pedal harder].
Sounds like a brake fluid and pad problem. What is the brake fluid brand and age in months and tested moisture content? Which brake pad code material [U90, U91*, U92, U93*] you are using? Various oem pads are available and most dealers don't know the good ones from the ones created to address customer dusting wear complaints.* common pads at dealers
New recent factory shim/insulator replacement? Age of brake flex hoses? Oem rotors or some aftermarket brand of inferior grade grey cast iron?How long since calipers were rebuilt [new seals and caliper bores and pistons cleaned and polished.
As the pads wear more than half from the orginal 9mm thickness the heat transfer accelerates and brake fluid may begin to boil in severe duty.
IF YOU EVER boil the brake fluid it must be flushed out and replaced IMMEDIATELY as it is never the same again and just gets lower and lower in boiling temperature due to chemical changes in the fluid........not to mention the acids that form from moisture + fluid and heat in contact with rubber seals!
The pads are what fade from exceeding the 600-650F temperature but you can find pads that go higher [Metal Master for aggressive street >700-750F] and racing pads that will survive 1000F at the expense of noise and bad cold weather stopping.
Usual problems are that the braking system has not be kept up to oem new standards.
A 10% heavier rotor [certainly not the one from a 300zx] will only lower the rotor temperature 10%.
Sounds like a brake fluid and pad problem. What is the brake fluid brand and age in months and tested moisture content? Which brake pad code material [U90, U91*, U92, U93*] you are using? Various oem pads are available and most dealers don't know the good ones from the ones created to address customer dusting wear complaints.* common pads at dealers
New recent factory shim/insulator replacement? Age of brake flex hoses? Oem rotors or some aftermarket brand of inferior grade grey cast iron?How long since calipers were rebuilt [new seals and caliper bores and pistons cleaned and polished.
As the pads wear more than half from the orginal 9mm thickness the heat transfer accelerates and brake fluid may begin to boil in severe duty.
IF YOU EVER boil the brake fluid it must be flushed out and replaced IMMEDIATELY as it is never the same again and just gets lower and lower in boiling temperature due to chemical changes in the fluid........not to mention the acids that form from moisture + fluid and heat in contact with rubber seals!
The pads are what fade from exceeding the 600-650F temperature but you can find pads that go higher [Metal Master for aggressive street >700-750F] and racing pads that will survive 1000F at the expense of noise and bad cold weather stopping.
Usual problems are that the braking system has not be kept up to oem new standards.
A 10% heavier rotor [certainly not the one from a 300zx] will only lower the rotor temperature 10%.