Oversized brakes 91Q45 Question...

[Rex Rich]

I have 19in wheels... They make the brake discs look extra small.I want to upgrade the brakes F/R on my 91Q to bigger dia ones.

Looking around I found some info:Nissan 350Z Track Model Big Brake Rotor Adaptor Kit For The 300ZXSPL big brake rotor kit..."Our big brake rotor kit allows the installation of the large 12.8" 350Z track rotors with 300ZX calipers on the S13/S14 or Z32".

Dose anyone have experiense with this setup on a Q? Do the adapters work on the rear?Are there REAR oversized Track Edition Rotors for the 300/350ZX...I think I heard that there are 12.7 Discs for the rear?If so would they work on a 91Q w/the e-brake and all?

Rex Rich

[elwesso]

Theres no upgrade for the rear, as theres no need to.....

Im planning on doing the 350Z rotors on my Q when i need new rotors (already have the 300ZX brakes)..

[Rex Rich]

Hey Wes do you know how I can get the parts for cheap?

[maxnix]

Theres no upgrade for the rear, as theres no need to.....

I mean, after all, Nissan never changed their rear brakes.

Didn't have to. Just needed to move some extra inventory, that's the only reason why.

http://www.stoptech.com/tech_i...shtml

[JohnPa]

Wait a minute. I seem to remember a NICO member stating that the calipers on the 97-01 Q were the same as earlier, BUT that the Rotors were vented. Can anyone confirm this, and if so, is there an advantage to upgrading???

[Q45tech]

The 97-01 Q rears are the same as J30 rear rotors.

Diameter is the same, as changing diameter means a change in master cylinder ratios and porportioning valve and ABS software.

All a trade off: pad life vs tire life.Performance cars should have pads and tires that wear out TOGETHER every 15,000 miles like the G35 coupe. Every 4 oil changes.

Unlike race cars with driver controlled brake bias cockpit adjustment for fuel consumption [rear weight changes], passenger cars must accept variable passenger loads.

[elwesso]

I mean, after all, Nissan never changed their rear brakes.

Didn't have to. Just needed to move some extra inventory, that's the only reason why.

http://www.stoptech.com/tech_i...shtml

I was referring to theres no upgrade for the rears past the regular Z32 upgrade, the Q45 stock brakes in the rear suck..... Menaing theres no upgraded rotors avaiable that use the Z32 calipers in the rear.

[Rex Rich]

"front-to-rear weight balance of the vehicle" Front to rear bias will be FDup?...So big discs on the front - little stockos on the back no problem?

Check this?http://performancenissanparts....=5480STOP TECH - 350Z / G35355x32mm Front328x28mm Rear

If the ebrake works with the OE 91Q setup would luv to go with it?

Any encuragment please?

[elwesso]

Wow.. youd spend 4 grand on brakes that really wont do you any good over Z32 brakes??

[Rex Rich]

Hell No!Good question but Im trying to get to another point do you think these work?Then Ill go through the hell of trying to get something cheap!

[elwesso]

Theyd work but those brake kits are so stupid for street use on the Q..... SO stupid!

Youd never find a street tire that wouldnt just lock those suckers up..... I mean, with ****ty pads i can sometimes get the tires to lock up with the stock Z32 brakes.

[JohnPa]

The 97-01 Q rears are the same as J30 rear rotors.

Diameter is the same, as changing diameter means a change in master cylinder ratios and porportioning valve and ABS software.

OK, but is this a better setup than the stock 90 Q rear brakes??

[Q45tech]

Doesn't weigh much more so the temperature rise would be almost the same.

In mountains speed is usually low so the cooling effect of ventilated rotors is low.

THe only way to know is measure the rotor temperature rise ACCURATELY with an IR device. ~~$65-$160http://store.autotoolexpress.com/raymintemwit.htmlhttp://store.autotoolexpress.com/thermometers.html

A single panic stop [from 60] only raises rotor by ~~ 150F.............even in 100F summer that's only 250-300F [depending on previous cool down time and unbraking pad drag.

Don't confuse endurance with a single panic stop.

[Q45tech]

http://delphi.com/pdf/techpapers/1999-01-0483.PDF

Brake thermal study to gasp the heating of various components.

More often than not the brake fluid is the weak link in multiple stops in summer.

Interesting to see the effects of near new vs very worn pads on fluid temperature.

[one ton garage]

Big brake setups that allow you to run a rotor larger than 12" with the OEM nissan 4pot calipers are a waste... with such a large diameter rotor, a great deal of the brake pad actually overhangs past the outer circumference of the brake surface, and you actually end up having less pad material doing the braking for you. Of course, most of these places don't consider stuff like that... they just think "bigger is better"... and of course, most people who buy those things are of the same mindset so they probably never really look into the details

[hannibal]

OK, but is this a better setup than the stock 90 Q rear brakes??

Yes, cause the 97-01 Q rears use 292x16mm vented rotors vs 292x9mm solid rotors.

[elwesso]

The question remains of HOW much better it is.. it is better, but is it really worth it?

Id say a better alternative would be Z32 rear calipers

[maxnix]

"front-to-rear weight balance of the vehicle" Front to rear bias will be FDup?...So big discs on the front - little stockos on the back no problem?

Check this?http://performancenissanparts....=5480STOP TECH - 350Z / G35355x32mm Front328x28mm Rear

If the ebrake works with the OE 91Q setup would luv to go with it?

Any encuragment please?

Look at Brembo or AP Racing. If cost is not a problem, Endless has a nice little 12 pot front caliper.

My BMW racing guy says StopTech are a little spongey on the track. He uses single or double pistons on his track BMW (holds the class record at Texas International also). He also says AP calipers hes examined do not have dust seals, so would not be good for the street, but AP website says they do.

Anyway, they do have a nice 35mm front rotor that would most likely negate warpage for life.

Talked to StopTech last year, and they have not interest in a G50. Would prefer to sell you hard Hawk pads.

[Q45tech]

http://www.nlectc.org/pdffiles...0.pdf

Study the pursuit to see how various pad compositions react and the pad differences front vs rear temperature.

The question is best simplified as 9mm solid vs a vented with 5.2 mm metal 5.8 mm of air space and again 5.2 mm of metal. A vented rotor of same diameter but increased thickness might weight 8-10% more [9 vs 10.4 mm metal plus support vanes], so the temperature rise will be 8-10% less............now whether 600F-610F vs 660F is significant is unknown depends on the pad...........on the street where 600F is almost impossible at 300F the 25F improvement is even less significant.

In a single full panic stop from 60 mph the temp differences might be up to 10-15F less.

You can have too much rotor for the street which will result in less than optimum pad temp rise.

[Peterofdevon]

Speaking of rotors/pads...

I need new rear rotors and the fronts machined for my 94. Whats the basic/cheap upgrade here for rotors/calipers for front and rear?

I dont need anything custom or performance..I just want smooooth braking and less warped rotor issues.

Thanks!!!

Peter

[hannibal]

The question remains of HOW much better it is.. it is better, but is it really worth it?

Id say a better alternative would be Z32 rear calipers

I agree. 297x18mm with 2 piston calipers...

Q45tech, I like how you always return to the bottom line: heat dissipation. Doesnt the vented rotor have an advantage in that the heat is removed from the rotor faster than a solid disc? Or should I be more concerned about pad temp vs rotor temp?

[elwesso]

Its all about heat capacity, the vented rotors dont hold heat any better since they weigh approx. the same..

IMO, it is still best to mess with the front brakes before you mess with the rear brakes...