My son and I want to clean up / simplify the engine compartment and entire dash on his '72 complete resto. We want to keep the rear drum system and e-brake, but get rid of the factory brake warning light system on the fire wall and the factory proportioning valve - install an Arizona Z proportioning or another aftermarket one. We're completely removing the dash and existing electrical so we don't have issues with warning lights. Any insight on the above reduction and simplification?

I've been thinking of the same thing as well...interested in hearing others experience.

I didn't see the value in installing the rear disk set-up. My son may disagree. But the crap all over the firewall -- proportioning valve then the warning light switch -- just don't want to go back with so much BS. He's going to know when his ride isn't braking right; no idiot light is gong to help him sleep. We like the idea of stripping it down to basic-basics. Having a real clean engine compartment, etc.

Hybrid Z link pretty much gives me confidence to abandon the warning light switch and plumb in a new knob style balancing valve in the rear brake line system wherever I want (probably next to stock e-brake). Here is the link:

Brake upgrade FAQ - Brakes, Wheels, Suspension, and Chassis - HybridZ

This came from another member with an incredible blog; grannyknot

Uncomfortable questions excerpted from the court transcripts of Murphy's Law:

"So, Mr. Plumbing, in what way did you feel removing the proportioning valve from the brake system of your antique vehicle would improve its braking efficiency or reliability?"

"We see that Nissan's OEM braking system was designed by some of the Japanese auto industry's top mechanical engineers. What are your own engineering credentials, and what other brake systems have you designed?"

"What laboratory or governmental agency certified your modified braking design safe for use on the public roadways?"

"When your vehicle rear-ended my client's vehicle, rendering my client unable to work, due to excruciating neck pain, is it at all POSSIBLE that your brake modifications -- in your EXPERT opinion -- might have contributed in some way to the accident?"

I'm not trying to be a smart-arse. I'm just saying that unless you're going to trailer your car everywhere, you shouldn't modify anything that could impact the safety of others, including your passenger, unless you're willing to risk this sort of questioning in court. Remember that any good ambulance chaser attorney is going to pay some guy to go over the wreckage of your car with a fine-tooth comb and note any modifications or safety problems.

Hmmmm... Is it possible that you could simply relocate the proportioning valve and brake light switch, perhaps to a location underneath the body?

Edited April 23, 201410 yr by FastWoman

I take it your 72 is after July 72 becuase you want to remove the proportioning valve from the firewall. In that case you could go to the pre July 72 system which has the proportioning valve at the rear.

It is static type, like the Arizona type, which means it is not balanced with the front system.

Removing the brake switch, although it would unclutter the engine bay, could have legal issues like FastWoman said.

Chas

I take it your 72 is after July 72 becuase you want to remove the proportioning valve from the firewall. In that case you could go to the pre July 72 system which has the proportioning valve at the rear.

It is static type, like the Arizona type, which means it is not balanced with the front system.

Removing the brake switch, although it would unclutter the engine bay, could have legal issues like FastWoman said.

Chas

I appreciate the cautionary warning. I desire to simplify without removing items which will increase risk. The two devices (brake warning light and proportioning valve) create six more connections and compound potential problems discussed throughout these blogs creating hair-pulling scenarios and by proxy allowing unsafe items to increase. I don't want to get rid of the proportioning adjustment, I just want to plumb it in a different place and create the ability to adjust it (if my son insists on the "cool" disk upgrade for the rear brakes at some point). I do, however, want to get rid of the "idiot lite" mechanism. I don't want idiot lites; line pressure gauges if I feel it becomes necessary to monitor brake line status would be the solution. The z has two independent systems already so I'm not worried about a "sudden and accidental" occurrence rendering the vehicle unable to stop -- three, with e-brake option.

I'm not a purist; don't want everything stock and unmolested. I'm not a mechanic; don't condescend to know more or believe I can design better or improve upon those who know better. I'm a dad, fearful of his 15 year old treating the roads as a playground, driving too fast, hurting himself or others. I'm a dad who said "Maybe if I buy a lift and find a fixer that's his ultimate dream car, I can turn his car obsession into a good thing rather than a dad-worrying-helpless-hell." And "Maybe if he spends countless hours getting greasy and cleaning currently unknown items and trying to understand how and why they need to go back, he'll remember this incredible investment of time and effort someday... when the urge to show-off or push the envelop creeps up... and think better!". I don't know, but I'm trying. And I do want him to feel a complete understanding of his build and choices in modifying so that his enjoyment of it will increase as well.

I take it your 72 is after July 72 becuase you want to remove the proportioning valve from the firewall. In that case you could go to the pre July 72 system which has the proportioning valve at the rear.

It is static type, like the Arizona type, which means it is not balanced with the front system.

Removing the brake switch, although it would unclutter the engine bay, could have legal issues like FastWoman said.

Chas

I appreciate the cautionary warning. I desire to simplify without removing items which will increase risk. The two devices (brake warning light and proportioning valve) create six more connections and compound potential problems discussed throughout these blogs creating hair-pulling scenarios and by proxy allowing unsafe items to increase. I don't want to get rid of the proportioning adjustment, I just want to plumb it in a different place and create the ability to adjust it (if my son insists on the "cool" disk upgrade for the rear brakes at some point). I do, however, want to get rid of the "idiot lite" mechanism. I don't want idiot lites; line pressure gauges if I feel it becomes necessary to monitor brake line status would be the solution. The z has two independent systems already so I'm not worried about a "sudden and accidental" occurrence rendering the vehicle unable to stop -- three, with e-brake option.

I'm not a purist; don't want everything stock and unmolested. I'm not a mechanic; don't condescend to know more or believe I can design better or improve upon those who know better. I'm a dad, fearful of his 15 year old treating the roads as a playground, driving too fast, hurting himself or others. I'm a dad who said "Maybe if I buy a lift and find a fixer that's his ultimate dream car, I can turn his car obsession into a good thing rather than a dad-worrying-helpless-hell." And "Maybe if he spends countless hours getting greasy and cleaning currently unknown items and trying to understand how and why they need to go back, he'll remember this incredible investment of time and effort someday... when the urge to show-off or push the envelop creeps up... and think better!". I don't know, but I'm trying. And I do want him to feel a complete understanding of his build and choices in modifying so that his enjoyment of it will increase as well.

I hope you didn't misunderstand my point. I didn't wish to imply that you don't know what you're doing -- or even really raise that question. Rather, I meant to point out that even if you DO know what you're doing, and even if you can make functional improvements to the braking system (e.g. with the 4-disc upgrade with double calipers), any attorney will use your modifications, good or bad, to destroy you.

With regard to the brake light: If your son should have a brake failure that the light might have forewarned him about, then that's a safety issue both for him and for others. Same issue. The brake failure light is not an idiot light. An idiot light is a light that is substituted for a more meaningful gauge, like an oil pressure light that comes on to let you know you've been running a dry engine for the last 5 min. But there's no better indicator of brake failure than a light. I remember once ripping a brake line, and my light was flashing at me about 2 brake presses before I would have lost all my fluid. I believe my stepson had a brake light that had been coming on for a very long time. (He's the mechanical engineer of the family, so of course he ignored it.) He was slowly losing fluid, due to a rusty caliper. His brakes did need attention.

Personally I'm thankful for any fault indicator in the instrument panel. That applies doubly with my kids and stepkids. I tell them very emphatically that if there's a light, THERE'S A PROBLEM. They've brought me cars with glowing lights, insisting that "the light just does that for no reason" because that's what some lazy mechanic told them. And then I find the problem and make the light go out. After doing this a few times, I think I've impressed on them that lights and gauges really do mean something.

Anyway, for my car, I want the brake light. For my kids' cars, I ESPECIALLY want the brake light, because they don't notice anything unless it's glaring at them on the dashboard, and really not even then. You should want a working light in your son's dash too. Surely there's a way to neaten up the wiring to the reservoir lids. Is there any wiring to the proportioning valve? (Some PVs have fault switches too.) One trick for neatening wiring is to wrap a solid piece of copper wire (12 ga would do for the brake wiring) together with the stranded wires with loom tape. That will stiffen the wire bundle, so that you can bend and form it neatly.

One final note: If you're worried that your son might be driving too fast and taking too many chances, there are much safer cars than the Z. You don't have to put him into a Volvo to keep him safe. There are even SOME modern cars that can be worked on. A rear-wheel-drive car with a 4-banger is generally roomy enough for any novice mechanic. I would put my own son in a Miata with a removable hardtop sooner than I'd put him in a Z. And FAIW, I also love my '92 Saturn SL2, which was the "family car" when my kids were growing up. There's a sports coupe version of the same car (Saturn SC) that I would highly recommend. It uses space frame construction and is tougher than most people would think. Mine has airbags and ABS, which were new options in '92. Anyway, there's space under the hood, even though it's front wheel drive. It's worth mentioning that I've driven stick my entire life, and I've not come across a better, more intuitive stick than is in that Saturn.

Edited April 23, 201410 yr by FastWoman

Fastwoman: I'm a dad with a son who has been working on sewer lines and doing wood chores since he was three. I tried to get him in a 635csi when the discussion of upgrading his mountain bike went south. That didn't work. He was stuck on the Fairlady. His money, mostly; our project.

Lawyers screw up everything, in my opinion. If we live in fear of what they may claim, we become as weak as them; saps who live off the wealth others create, for the most part (btw: my 15 year old wasn't allowed into Pick-n-Pull this weekend because of some punk legal claim. That's the revolution I'd love to partake in; tort reform in every form).

When we learn how to post pics on this site, we will. Thanks for the cautionary advice and I'll post our brake mistakes soon I hope.

Click the "go advanced" button, then scroll down to "manage attachments" then click on "add files". Find your pics then "upload files". Drag them down to the bottom bar, then "Done" or "insert inline". That's how I do it.

Working on sewer lines since he was 3? and your worried about a brake "Idiot" light? You need one.

Edited April 23, 201410 yr by siteunseen