Stock Brakes vs. Upgrades

[kce]

So I got all fired up about doing the Toyota S12 caliper swap in the front and rear disk conversion but them I returned to the FAQs (see I do read them!) and thought about this:

 

The stock Z brakes are adequate for street driving' date=' autox, and drag racing.

The stock Z brakes are adequate for street driving, autox, and drag racing.

This is not a joke. Even with a V8 or turbo pushing lots of hp;

The stock Z brakes are adequate for street driving, autox, and drag racing.[/quote']

 

 

 

Well if that's the case, then why bother at all? I know 'adequate' is a relative term but for someone like me whose car is going to see 95% street and *maybe* some very causal autocross racing and a pass or two down the strip, should I even concern myself with upgrading the brake system? I spent quite a bit of money upfront on the car, so luckily the brakes are in great shape. Should I just look into some nice brake pads and cooling ducts and call that good?

 

Your advice and taunts are welcome before I spend thousands of dollars (that I rather use of build a 500hp LS1 ).

[FlatBlack]

Heh. Thousands of dollars?

 

I think I have less than $100 in my S12+8 upgrade.

 

I just did new rotors, rebuilt calipers, and bought new pads. I will be upgrading to SS lines soon.

 

The stock brakes are alright, but I'm very glad I switched. Also, they have a nicer aesthetic value, seeing 4 pots are way better than seeing one big round caliper.

 

My brakes are front biased now, but a cheap rear disk swap and proportioning valve will fix that. I would guess 40% of my driving miles this year have been directly related to autocrossing [traveling to events and then running in them], but they help on the street as well. I like the pedal feel over the stock calipers as well.

 

Do you need them? No. Do you want a really good upgrade for cheap? I don't know, I don't read minds

Edited October 1, 2010 by FlatBlack

[kce]

Heh. Thousands of dollars?

 

I was exaggerating for comedic value.

 

So do you feel like the handling and brake feel was substantially improved? I mean for that amount of money, it's almost impossible not to want to a caliper swap.

[goodoldjam]

A upgrade wouldn't be that beneficial to me ATM. If I can't use more stopping power then why do it.

One of these days I'll hunt down the parts, right now I'm thinking being able to use what I have to it's fullest is probably what I should be focusing on.

If my brakes weren't in decent shape I would consider a upgrade as long as I was there, it really isn't that much.

[ktm]

Seriously, read it again:

 

The stock Z brakes are adequate for street driving, autox, and drag racing.

The stock Z brakes are adequate for street driving, autox, and drag racing.

This is not a joke. Even with a V8 or turbo pushing lots of hp;

The stock Z brakes are adequate for street driving, autox, and drag racing.

 

It is true. Many people upgrade to disc brakes "just because" or because they believe there is a perceived difference. You can lock up the fronts with the stockers just as well as with Wilwoods on a street car. Others upgrade for valid reasons such as tracking the car (I am not talking Auto-X).

 

My stock brakes were fine for a while, but I upgraded because my fronts needed rebuilding and my rear drums were shot. I managed to get great deals on parts for sale and it cost me the same as buying reman'd stock parts. Would I do it again? Yes, because disc pads and rotors are easy to come by and are relatively inexpensive compared to drums.

[bjhines]

Street, AutoX, and drag are certainly not all uses for these cars. Track-days and Road racing make great use of the upgrades. I can tell you from experience in a variety of cars that the Datsun S30 stock brakes are a handicap on a race track. They just suck in SOOO many ways.

 

The 1984 300ZX rotors(front and rear) with appropriate hydraulics and brackets are a FANTASTIC upgrade for track duty.

Edited October 2, 2010 by bjhines

[cygnusx1]

In racing, size matters.  You need to have a place to dissipate heat.  Although stock brakes do work well, they quickly become too narrow a path for heat to flow through.  This is especially true when you start talking about 300hp+ Datsuns on a race track.

[bjhines]

I have a friend who runs stock brakes in ITS class. He has the skillz to manage the heat on track. It is still his main handicap, even with the stock L24 engine.

 

I don't like the way the pedal drops when the drums heat up. The main disadvantage of the drums is not heat dissapation. The drums grow in diameter which causes the slave cyl to displace much more fluid when the drums peak in temps. This causes the pedal to drop whenever the drums are really hot. I find that I had good pedal after a long straight, but a series of turns would cause the pedal to drop further and further as the heat built up after 2 or 3 consecutive braking zones.

 

Rear disks are much more consistent. The pedal stays the same height until you crack a front rotor. I have found that modern race friction compounds can stop the car no matter how hot they get. The front stock disks will crack with abuse on track. You can also boil the grease out of the hubs. I pulled in missing my front grease caps a few times from heat and pressure.

[AkumaNoZeta]

What I've been thinking for my car is since it will be a 100% street car basically that I will keep the stock brakes and since I want manual brakes, get a dual master cylinder set-up with a balance bar so I can tune the front:rear braking ratio for better efficiency.

[RTz]

Rear disks are much more consistent.

 

Exactly.

 

I've swapped a few S30's over to modest rear discs, purely for consistency. Most of my activities are street and autocross (where repeatability wins races). Stock fronts, appropriately sized rear discs, prop valve, and a proper set of pads have served me well... even with V8 power.

[strotter]

I have to agree that, under normal circumstances, the stock S30 brakes are more than adequate. That said, though, I have managed on several occasions to fade them to scary worthlessness; I live near the Sierra Nevada mountain range, which is criss-crossed with wonderful driving roads. Not so much high speed, but with significant, long, altitude changes. Even slightly spirited driving on downhill sections will quickly fade the system, so much so that I've had to pull over for a while to allow the system to cool. More brake = better, under those circumstances. Even so, however, I have no plans to upgrade.

[h4nsm0l3m4n]

When I switched to rear disc brakes I didnt feel a huge difference in terms of braking power. However, consistency and ease of maintenance are much improved. Also with the 240sx caliper setup you have a huge selection for brake pads (including R compounds) for further tuning in your application.

 

Though stock brakes and good pads work great for autox and street driving I suspect if frequent track days are in your future vented rotors are going to be highly desired. I also feel that if youre doing a V8 swap with high hp some front brake upgrades are good insurance. I'm upgrading to toyota calipers and vented rotors alongside my LS1 swap. I figured with 400+ hp you can get going very quickly very easily. A couple hundred bucks is not much compared to the net cost of swapping the LS1. For me I saw little reason not to go through with it.

Edited October 2, 2010 by h4nsm0l3m4n

[Leon]

I have to agree that, under normal circumstances, the stock S30 brakes are more than adequate. That said, though, I have managed on several occasions to fade them to scary worthlessness; I live near the Sierra Nevada mountain range, which is criss-crossed with wonderful driving roads. Not so much high speed, but with significant, long, altitude changes. Even slightly spirited driving on downhill sections will quickly fade the system, so much so that I've had to pull over for a while to allow the system to cool. More brake = better, under those circumstances. Even so, however, I have no plans to upgrade.

 

The stock brakes are adequate. Friction material selection is critical to proper brake function. Organic materials will work better at lower temperatures and semi-metallic materials are more well suited for high temperature. There are options in between so you can essentially pick the right friction material for your situation. The pedal may get softer, but you should not lose brakes to a point of it being dangerous if you're using the right pads and shoes.

 

Like has been said, switching to rear drums is better for consistency because of the tendency of drums to expand under heat and inherently not dissipate heat as well as disks. If you race and the rules allow it, I'm sure it's a worthwhile upgrade.

[josh817]

The stock brakes are adequate. Friction material selection is critical to proper brake function. Organic materials will work better at lower temperatures and semi-metallic materials are more well suited for high temperature. There are options in between so you can essentially pick the right friction material for your situation. The pedal may get softer, but you should not lose brakes to a point of it being dangerous if you're using the right pads and shoes.

 

Like has been said, switching to rear drums is better for consistency because of the tendency of drums to expand under heat and inherently not dissipate heat as well as disks. If you race and the rules allow it, I'm sure it's a worthwhile upgrade.

True that. I went to a track a week or two ago. I'm not particularly fast but there were some long straights where I was seeing 120+mph and then hard on brakes. Whatever pads I had, probably nothing fancy, they died after 20 minutes.

 

Use proper pads and proper brake fluid and it will work out. I killed pads and fluid got too hot. The consequences were when I put a lot of pressure on the pedal, I couldn't lock up the brakes at all and it felt spongy. After 20 minutes you could smell them and the pedal went all the way to the floor. I had to wait 3 hours until I got a little pressure back so I could drive home, however the pedal is still very very light.

 

So... proper fluid and pads and maybe some ducting to the front brakes, I bet it would work out well for what its worth.

[cygnusx1]

 There are more than one persons that use the handbrake lever to compensate for heat expanded drums.  Try lifting the lever a click or two and see how the pedal feel changes.  

Edited October 3, 2010 by cygnusx1

[bjhines]

See...^^^^ I never did that because what happens when they cool down. You click a few clicks on the adjusters and the brakes will drag badly when they cool off. There is no easy adjustment for when they cool off again, Not without removing the wheel and turning the adjuster with a screwdriver.

[josh817]

 There are more than one persons that use the handbrake lever to compensate for heat expanded drums.  Try lifting the lever a click or two and see how the pedal feel changes.  

Oh trust me I was trying everything I could to stop the car. Coming in way too hot and then your brakes are dead and its just like.... FUUUUUUUUUU. I have a feeling when I take the wheels off tomorrow and check the drums, one or two of them are going to have very little to no pad left. The front rotors are already chewed to smithereens. They look like really crappy records, Kris Kristopherson records.

[cygnusx1]

If you just lift the handbrake lever a click or two, it probably won't trigger the starwheel adjusters to move to the next notch...at least I never had that issue with hard STREET driving.  I never tried it on the track myself.  After my turbo swap I went out on Limerock with the stock brakes and good pads and shoes.  In the last session of the day I boiled the fluid coming into turn one.  I used the runoff, down shifted and made it around the next couple of laps with hardly a brake pedal left.  I was probably overusing the brakes as a newbie on the track but regardless, I don't EVER want to fear that my brakes are my limit, of all things, not the brakes!

[josh817]

I know what you mean. Once my $50 crappy tires seemed to be cooperating with me and I was getting use to the what it felt like to get loose and stuff, it started getting fun. Two laps later and my brakes were getting unpredictable. After they were gone I came in and a dude gave me a ride in his Evo I think it was with the paddle box and Brembo brakes and thats when I felt what good brakes were suppose to feel like. Stopping distance for me lets say was at the 300 marker, his was at the 100 or less, going quicker in a heavier car.

[kce]

Though stock brakes and good pads work great for autox and street driving I suspect if frequent track days are in your future vented rotors are going to be highly desired. I also feel that if youre doing a V8 swap with high hp some front brake upgrades are good insurance. I'm upgrading to toyota calipers and vented rotors alongside my LS1 swap. I figured with 400+ hp you can get going very quickly very easily. A couple hundred bucks is not much compared to the net cost of swapping the LS1. For me I saw little reason not to go through with it.

 

This is pretty much my thinking as well. I figure if I can spare the 4-5K I'm planning for the engine build, then I can spare a few hundred to upgrade the braking system. I also like the idea of rear disc conversion simply because of the ease of maintenance compared to drums. However, if it's not an absolutely necessary upgrade for the kind of driving and power I'm planning on, I will probably just stick with the stock system.

 

There's so much work I wanna do with the car, I'm having problems figuring out where to start! Suspension, brakes, engine, interior?