RebekahsZ

The parking brake return spring is on the wheel end of the cable near the spindle pin. That could rust and break, or it is often removed for a disc brake conversion.

Drill that hole like johnc said while the drum is off. A regular bit works fine and the drum is usually aluminum, not iron, so it drills fast and easy. Get step bits from Harbor Freight for $9-ish. Go ahead and get one-I can't live without mine. If you don't find anything else, try disassembling the parking brake cable to clean and grease it. That is a good place to have a bind.

I found the hassle of a rear bar not worth the trouble. With CV axles, the link clearances are very very tight. I could get things to clear on the jack stands, then things would rub at ride height, or vice versa. Finally said screw it and ditched the rear bar. As a novice driver, I did an autocross with morning runs with the bar installed and afternoon runs with it removed. I could not appreciate a difference either way. If you have a V8 car with stiff springs and CV axles, I don't think a rear bar passes the performance to hassle to dollar to time test. I know this idea doesn't pass the bench racing logic, but perhaps I can save you some trouble.

My bad: Smyrna388Z

Need clarification. Which component goes into the differential as an output stub or side-axle flange? I want to google a picture of that part. Pics of your prototype as soon as you have time (and don't flunk out of school).

I'm glad this is being discussed-I'm looking to get a set soon. Please post the outcome as you figure it out.

I have been lucky for two years and my luck seems to have met its match with the 28x10.5 tires. I don't think anybody makes a 28" that is any narrower?? I will look but I don't think so. I need the 28" tall tire for gear ratio, but I think I might be willing to give a little on traction if it lets me hold up. I was pulling occasional 1.4 60' on the 26x8.5s. SunnyZ, I guess each diff has its pros and cons: a welded diff lets you one-leg it home and the CLSD lets you drive out broken a LR since it has no cross shaft. Learning, learning, learning. Who knows, this may have been propagation of a crack that started last year on the smaller tires.

Inner CV replaced. Car still down awaiting a diff output seal. Total damage: broken inner CV at the thickest section 1.25" diameter, slightly torn inner CV boot, some scratches and burrs inside diff carrier where the stub inserts, diff output shaft seal. Diff was slightly over-filled with friction modifier. I'm getting better with these axles. Wound up pulling passenger side axle also so that I could easily drive the broken stub out of the driver side (an LSD has no cross shaft), then put passenger side axle right back in. De-burred carrier. And side seal sealing surface with dremel tool. Trusting any metal chunks to fall to bottom of diff oil. Put axle on vice, mounted on shaft. Mark location of boot. Cut off old torn boot. Steady tug on inner CV while smacking hard with metal 3# shop sledge. Removed inner CV from donor axle same way. Clean out donor inner CV with gasoline and clean, clean, clean then regrease. Easiest way to regrease is to squirt grease into female splined inner CV, then insert splined axle shaft into hole to force grease past ball bearings. Repeate until grease is clean. Put new CV boot on shaft (Ive forgotten this before). Put inner CV on splined shaft. Take to press and have wife slowly press assembly while I massage c-clip into groove. Secure boot with big hose clamps.

I will soon be heading to the local Nissan salvage horde to gather up as many axles as I can get. There were as many as 6 candidate cars. I will be working in mud on my back with spiders and chiggers and mosquitos and thorns and snakes. Do any of you have any special instructions to help make removing these axles more expedient? Please let me know if I go straight to the 4 bolts at the outer CV with a crows foot wrench and a breaker bar or if there are any other assemblies that I will have to remove first. I am a S30 gyy and have never bern underneath a Z31. Any tip is welcome.

I plan to go with 275x17 in front and 315x 17 in rear. (I am at 245x16 in front and 275x17 in back currently). I use purpose built tires: hoosierR6 (track day)and A6 (autocross), the cheapest thing I can get for the street (because I drive slow on the street and like to so big smokey burnouts with the line lock on), and dragstrip tires (currently 28" Mickey Thompsons, but I may get Hoosiers next). So I don't really care about brand for street tires. I'm looking at dropping my front RBR width to 8.5 in order to get better offsets (the 9 and 9.5 s don't take advantage of the space made available by coilovers). The 275s may hang over a bit but i think they will be OK. I may even look at wider than 315s in back for autocross. I buy all my tires used that I can to help offset my guilty pleasure.

You will get a bunch of opinions and you have done more of the Z-thing than I have, so I post this respectfully. I would avoid media blasting to avoid loss of what little factory rust protection these cars had. If you go V8 and plan to go fast on a regular basis, back-half the car with a solid rear axle. After a grace period of several years, I'm starting to go thu the broken axle phase. I concur with the plan for automatic, especially since this is already an automatic car. It looks like an amazing starting point.

I searched and this may already have a thread, but I thought the info was valuable. I saw a roll bar main hoop in the Z-car owned by screen name SmyrnaZ at ZAttack in Nashville this past weekend. The main hoop fit like a glove! Every bit as good fit as the custom main hoop I just paid megadollars to have made. I asked SmyrnaZ where he got it. The answer: JCWhitney! The price: $77. Just want you guys who are making cages to know about this. I don't know any of the specs on it, but it looked to be 1-3/4" tubing. This option will make installing a roll bar only setup or even a NHRA 6-point cage a very do-able weekend project for anybody with a mig welder who knows how to use it. Contact SmyrnaZ for details. Sorry no pics. The bar was black and the interior was black with sun streaming thru the windows-my pics came out too poor quality to post.

Buy a huge rubber dead-blow hammer. Make sure parking brake handle is down. Smack the ever-living snot out of the drum at the curved edge between the flat face of the drum and the fins. If you hit on that curve, you are unlikely to hurt anything. But if by chance you shatter a drum, you are half way there. Wear eye protection. Hit it HARDER! Stand up and smack it some more. Use both hands.

Yeah, and I'm missing having a parking brake too, cause leaving car in gear to hold on a hill doesn't work with a broken axle. Since I have 7 R200s and 3 sets of CVs and 2 sets of shortened center bars, I'm gonna stay R200 a bit more-just too heavily invested. I rigged up a winch on the floor of the garage plus a couple of tow ropes to winch the car up my steep driveway (another special tool). So now when I break the driveline, whether it be a driveshaft or an axle, I will at least be able to get the car into the shop. Car is in shop now and I have tomorrow off. Will tear into it and see what we've got. Ordered a pile of output stub seals today.

Gonna build up an axle today before pulling broken one. Is the driver side the short inner CV or the long one?

I don't know a thing about auto trans-never had one but I'm thinking about it for next car. Why are you changing from the 700R4 to the 4L80e? Seeking only to learn; no leading bias.

That's reassuring. Maybe I'm just out an inner CV. Jon, your axle shaft still looks great. Can inner CVs (the splined output stub portion) be heat treated or something to add strength?

Looks great!

A few days after bragging about my rearend, I just snapped aCV axle. Pretty sure it is at the same place SunnyZ was snapping them. I think it is worth noting that I dead-hooked the car three times in a row from a 3000 rpm 2-step with 10.5" slicks onto a VHT coated track that was sticky enough to yank your shoes off. Either way, I just joined the club. If you are going to drag race it, think about a solid axle and be done with it.

I've had good luck with 200# for over 20 years. On thing you can count on: I've made every mistake on my car that you can imagine. And I've usually found the solution on this site with help from someone else.

This should probably be in drivetrain but most of my racing buddies pretty much stick to the Gen III forum. First trip out of the stable since switching to koni yellows and 28x10.5 MT bias ply slicks. Same 3.54 R200 CLSD and shortened Z31T CV axles as last year. Last year i was spinning the 26x8.5s at any track but the most immaculately prepped. Set konis full stiff (full rebound dampening) in back and full soft (least rebound dampening) in front. Put 15# in the slicks. Set 2-step at 3000. First pass: .539 rxn (.500 full tree), dead hook, 1.6 60', 7.18 at 99mph, straight as an arrow (oddly straight for bias plies). None of last years spinning, hook-spin-hook; no bouncing or porpoising. Second pass: dead hook, 7.22? Didn't like the dead hooking, so I pumped tires to 20# to reduce contact patch and allow a little wheel spin (that's what I was thinking anyway). After 5000rpm second gear burn out (no tire hop), staged, dumped clutch on the last yellow light and "BANG!" It was pretty unexciting in the car, but the track photog said the hood jumped up a couple inches. Pushed me against the back fence where the sprayer parks. Had me pull up trailer and winch it up. All the VHT about sucked the tires off my truck as I tried to avoid the groove as I went down the track. No oil leaks until I tilted car as it went up trailer ramps cleaned trailer up before pulling truck ahead. A circular spring (side axle seal spring) and some metal chunks were found at the line. Right axle is fine, left axle snapped but still in place, not flopping around. Looks like I snapped the splined portion of the inner CV, same as Josey was doing. It really sucks to have a steep driveway at times like this. Wondering if CLSD is fubar too, since it used to have 45# break away-would that make car moveable (it's not)? Jealous of Josey's old welded diff in terms of ability to get car up driveway. Lots if questions: air pressure too high, or just living on borrowed time after two years (tons of hot lapped passes) of living dangerously? May try to replace just that CV and do the repair in the street. Maybe it will rain, just to make life interesting. It seems to rain like hades everytime I break a driveshaft. If this keeps up all summer, car is getting back halfed this winter but will remain manually shifted.

Make sure you have torqued your stub axle before deciding something is wrong. My caliper was really tight on the rotor. Then I tightened stub to 200# and the rotor spun freely. I didn't need any spacers-it was bolt on for me.

Looks great!

Maybe a certain engineering student at Fayetteville? How does he have time?

IDK! I feel like I'm on borrowed time. Going from 26X8.5s to 28X10.5 adds a lot of rubber for traction, but it also gives me more sidewall to absorb shock. I also think I have SO much driveline slack in all the components. I've never spent any time checking the ring-pinion lash when I've done the CLSD conversions, but I'm going to spend some time on the next diff I build up. But, most of the slack seems to be in the T56 tranny!