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stock power(?) brakes?..with a 350??


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The 240 I just bought has a cute little booster behind the master cylinder..but someone just told me that the early Z's didnt have power brakes as an option..is this true? It sure looks like a small power booster to me and it has a hose hanging off of it that looks like a vacuum line.

 

The previous owner said it "stopped on a dime". I find this amazing considering the front disks are toasted. How well do the stock brakes (in GOOD condition) stop a mild V8 Zcar? Are they safe and predictable?

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Guest Anonymous

A couple of things to check. It does have a booster, just a little one. First, check the booster operation. With the car off, put your foot on the brake pedal and start the car. If the pedal goes down, the booster is working. If not, it isn't. Now why it isn't could be a couple of different things. Check the connection and the hose to ensure that it's good. If your engine is radical, it may not produce enough vacuum to power the booster. If there is sufficient vacuum, it may be the booster. I had to get one used for my 77, and it ran $50 from Mr Z in Albuquerque. Mine went bad from a leaky master cylinder.

Hope this helps.

Ct..

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Forgot to mention I also run a vacuum canister from crane to help as I have a bit of a cam in my 355. Seems to help,replaced booster as well. Not a hard job,couple of hours. Good luck. Mike

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Thx for the responses guys.

 

I've done some searching around and found the "Toyota 4piston upgrade". All the threads I read seem to jump al over the place tho..outlaw this and 5lug that.

 

Can someone explain exactly what parts I need and from which year of which vehicle to do this upgrade? Is it a direct bolt on to the datsun spindles?

 

Sorry if this is a rehash of info. I know the info is around the board already but its too mixed up and I'd just like info on the toyota caliper/disk swap..nothing fancy (read expensive).

 

Any help would be appreciated!

 

Jason

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I thought all 240s had a booster. My '71 does.

 

Regarding braking capabilities, I've said it before and I'll say it again, the stock setup in good condition with fresh brake fluid and with decent lining materials (Metal Master, Porterfield, CarboTech, Hawk, etc. up front and stock Nissan (NOT Pep Boys, AutoZone, etc) shoes in back) will work far better than most realize.

 

That's what I've been running for years, and I can brake with modern cars with much more impressive brakes easily at the track, even after 20 minutes or so of hard usage.

 

Of course if you have over 200hp AND do extended lapping sessions at the track, you might need more. For a street or strip car, you do not.

 

Braking performance is limited by tire grip, and no amount of $$ spent on bigger better brakes will change this. If you can keep the stock system balanced, and don't have problems with overheating the fluid or lining materials, it ain't too bad.

 

Dan Baldwin

'71 240Z 3.1

COMSCC #7 SPB

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Guest Anonymous

Good points Dan. I have 4 pistons up front with the 79 power booster and stock rear drums. This setup puts me against the 5 points really quick when I forget that I am not driving the Conversion Van. ;o) I am thinking that I will go to the disk rears with a proportioning valve. That's about as far as it will go.

Ct..

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Okay... so far as I know all had power brakes. In order of "upgrades" here's how I see it based o nthe research I've done:

 

1) Stock everything with upgraded pads. Okay performance but watch your speed and following distance smile.gif

 

2) Toyota calipers with good pads using stock solid rotors. Better but not super duper. I had these on my car until recently and I thought they worked well. The pad size is about twice sttock and you'll have 4 pistons on each side for even pressure.

 

3) Toyota calipers with vented rotors. Damned nice with the same size pad as #2 but with better fade resistance due to superior cooling. Can be done 4 or 5 lug.

 

4) Outlaw calipers with 12+ inch rotors up front on aluminum hats. Sprung weight plummets, you get 4 pistons at each corner (SCCA is working up a rear disk setup for me using this), looks awesome! Only downside I'm aware of is lack of dust seals on the calipers. Tire traction will be your biggest problem here as I expect this to stop to the limits of your tires smile.gif

 

I'm going Outlaw all th eway aorund. My 5lug Toyots setup shipped th eother day and I've got a 4lug solid rotor setup on hold for another member here. Rear disks have been the biggest problem as 240SX calipers require welding and are ugly iron single piston. Outlaws out back will require a custom bracket, MikeSCCA is making one of these for me but it will require Wilwood spot calipers for an E-brake in addition to the $80+ dollar Outlaw rear calipers. IMO this is an awesome setup once you've found out how much those 240SX calipers cost (cough). If this is interesting to you get with SCCA please. I'd like to see lot's of folks try this so he won't have spent a ton of time in development for just one sale... I'll document it when I set it up, Mikelly has already documented the front setup.

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Can someone explain exactly what parts I need and from which year of which vehicle to do this upgrade? Is it a direct bolt on to the datsun spindles?

 

After reading some of the responses..Im wondering if a fresh stock brake setup would be enough for my 350Z..maybe so

 

BLK what do you have for sale and how much? (Im gonna go check the buy/sell area next so if its there..ignore me smile.gif )

 

 

 

[This message has been edited by Racin_Jason (edited March 15, 2001).]

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Any braking system in which the tires are not the limiting factor is inadequate. On my track-driven Z, ~2500 lb. with me in it, ~190hp, the tires (sticky Hoosier R3S03s at that) ARE the limiting factor. (Note: track tire size of 225/50-14 means I get VERY good leverage against the pavement. Brakes are PLENTY responsive with 225/50-15 street tires, too. Taller tires DO require increased effort at the pedal for the same deceleration rate, though energy dissipation remains the same.) At tracks like NHIS, Lime Rock, Watkins Glen, Mosport (check here: http://www.comscc.org/~comscc/results/index.htm for lap times), brake pedal remains FIRM for 20+ minute lapping sessions. For longer than that, a couple of clicks on the parking brake *may* be required to adjust the rear shoes on the fly. Again, I'm running STOCK calipers, rotors, wheel cylinders, drums, and shoes. I'm currently using CarboTech Kelated Metallic pads, but have also used Porterfield R4s and Metal Masters with no problems. I use Ford heavy duty brake fluid (cheap, with a 550F dry boiling point), which I replace before each track event. I do have braided stainless flex-lines.

 

If you absolutely MUST do an upgrade, consider the solid-rotor '79-'83 Toyota 4X4 truck 4-piston calipers. This can be done pretty cheaply and easily. Only parts required are the calipers. Only mods required are rebending of the hard lines and trimming or removal of the backing plates. Front/rear brake bias is minimally affected.

 

As for me, my Z money lately has been going into aerodynamics (spook, spoiler, headlight covers), suspension (offset rear control arm bushings to zero the toe). The next wad o' cash will be going to the cylinder head (porting, decking for compression increase).

 

Bottom line: Why spend money on mods that won't make you faster?

 

Dan Baldwin

'71 240Z 3.1

COMSCC #7 SPB

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Right now it looks like both of my brake setups are sold. I'm waiting on cash before shipping my solid rotor 4lug stuff but right now it's spoken for. 5lug stuff has been shipped to Miami already smile.gif

 

IMO the solid rotor stuff worked okay. I never got it hot enough to fade but since I'm upgrading I'm going to go with th egood stuff. Yeah, I could probably get away with a lesser upgrade and I even had the parts here ready to mount but... I guess partly due to the looks and the knowledge that the bigger stuff will stop that puppy like RIGHT NOW swayed me to the Outlaw stuff. I'll go with as big a tire as I can too in order to take advantage of that leverage too. (shrug)

 

Whatever you do - upgrade the stock stuff! Heck, I'm selling off my solid rotor setup - pads, rotors, and hubs, for only $150 +shipping. For double the pad size and 4 pistons that's not too shabby! Rear disks aren't really needed but I'll be darned if I wanted to tinker with drums ever again - ick! smile.gif

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most of what we do with these cars is looks (well a good portion) other wise why paint it and have nice rims. IMO tiny little brakes under a 16+ rim looks silly.

 

so to those who say stock is fine "it is" BUT its FUGLY! stock suits a stock Z or a specific class of racing not highly modified street cars. i laugh at honda's and such that have dinky little brakes under 17" rims looks sooooo stupid!

 

------------------

Mike

mike@fonebooth.com

http://www.outlaw-brakes

raceparts and brake upgrades.

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Regarding leverage, taller tires give you REDUCED leverage, for acceleration and braking, as the extra height is INcreasing the torque required for a given level of acceleration or braking. I can definitely tell the difference between 225/50-14s and 225/50-15s, the 14s offering better acceleration and more braking gs per pound of pedal effort.

 

I totally agree with BLKMGK regarding tinkering w/ drums, what a pain. I discovered this past season, however, that by going back to Nissan shoes (had been using $$ racing compound), I didn't have to adjust them NEARLY as much. Once a day at the track, compared to once per session. Tolerable at the moment, but I'll probably go to disks one o' these days...

 

As far as FUGLY goes, to me super-tall wheels/tires on a small car like a Z give a sorta wagon-wheel appearance, especially if the wheels are FWD offset. Seems to me the whole trend in the large-diameter direction is to scale the wheels up to match the current crop of HUGE cars. I think that was one of the problems with the first Z concept, it was a decent-sized (i.e., reasonably and appropriately small) car on too-tall 18" wheels. Looked like it was on tippy toes. So they "fixed" it by replacing it with a positively IMMENSE car on 20" wheels! yuk.

 

Shorter wheels => less unsprung and rotational mass, better gearing, lower c.g. height

 

Dan "less is more" Baldwin

'71 240Z 3.1

COMSCC #7 SPB

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Ah, by larger I meant contact patch. I intend to run as wide a tire as I can in the stock fenders and in the back it will probably be a drag radial like the Nitto as I understand it's not too bad on the street. Taller tires do indeed give the wheel more leverage - this is why I shiver when I see jacked up trucks with stock brakes! However in my case I'll be going from whatever size rotor Nissan installed to a 12.19X1.25 rotor - a bit bigger in itself which will provide more leverage to stop. I hope that my tire height won't change that much to be honest but I'd like to get the sidewall down some. I've even considered going to 16's instead of 17s, 18's are a big no way!

 

The car I'm looking at for wheels has 18's on it but I think the 17inch will work out well -> drside2.jpg Those are 18X8.5s - I'm looking at 17X8 for 245 series tires.

 

 

 

[This message has been edited by BLKMGK (edited March 16, 2001).]

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Yes, exactly. If you go with a taller tire you've got a greater lever on the brake rotor that will reduce the brake effectiveness. However I'd hope that a taller tire might have a greater contact patch - but I'm not sure. For my taller tire I'm more than willing to compensate with a bigger rotor though. They should be showing up for the front brakes here pretty soon - vroom!

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I mentioned that I was using CarboTech Kelated Metallic pads. This is incorrect, I'm using CarboTech PANTHER pads. Just ordered a new set and Larry at CarboTech set me straight. The Kelated Metallic compound is used at the front for street/autoX ONLY. Kelated Metallic may be used for the rear shoes for track usage, however.

 

BLKMGK, I now see that we've been in agreement all along about leverage. i.e., taller tires have greater leverage against the brakes, so the brake pedal has reduced leverage against the tire contact patch.

 

Dan Baldwin

'71 240Z 3.1

COMSCC #7 SPB

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Dan, I think it's a drag racer thing, and I'm not going to try to debunk it. I think the theory is that the larger diameter tire will have a better SHAPE for putting power to the ground - a longer patch for/aft.

 

------------------

Pete Paraska - 73 540Z - Marathon Z Project

pparaska@home.com

Pete's V8 Datsun 240Z Pages

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Contact patch area is approximately the weight on the tire divided by the pressure.

 

So a 275/40ZR17 will not give you a significantly increased contact patch area than a 175/80-14. A wider tire will, however, give you a better contact patch SHAPE for cornering.

 

I still don't see why so many people think that a TALLER wheel and tire is better for performance.

 

Dan Baldwin

'71 240Z 3.1

COMSCC #7 SPB

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