Jeff Berk

I installed a temporary set of gauges to monitor the temperature of the radiator at upper hose inlet, engine compartment at fuel rail, oil at oil cooler connection and of course, the differential at the fill plug. Unfortunately, the two digital gauges have an upper limit of 120C (248F) and I think I've already exceeded that temperature in the engine compartment. The two dial gauges have a range of 40-140 C (104-284F). I currently still have the stock diff cover installed and I want to conduct a few autocross events to get an idea of what heat level I'm looking at. I'm taking the new diff cover to the machine shop to drill and tap the fill and drain holes on Monday. I drilled one of the mounting holes too deep and it broke through but I'm assuming Teflon(tm) tape will withstand the temperature. After this step, its ready to go except I need to create a modified rear transverse to clear the fins on the new diff cover.

So you don't own anything newer than around 2005?

Although I'm constantly tinkering with my '74 260z, I find it very rewarding when I make a discovery, learn to do something new, or fix a system that I never knew how to fix. I definitely spend more time under the hood than in the driver seat. I was reminded of how enjoyable it is working on this Z today when my 10-yr-old Chevy Volt stopped recharging and I had to take it to a dealer. My OBD II scanner could not read hybrid codes because I needed the $5K unit to read the recharger module codes. The dealer charged me $180 to start diagnosing the problem then told me to continue trouble shooting the problem I needed to give them $700 more. The cause of the problem was one of three issues. The cost for the most likely problem, a recharge control module, would end up costing me $3K+ to replace. This on a car worth $4K. I got lucky and after the 1st $180, I called a small repair shop within walking distance of my home and found out that he has personnel trained in working on rechargeable hybrid cars. I'll still have to pay $1.2K for the part, but I can avoid the near $200/hour labor.

The voltage regulator (engine side) to ground is 0.2 ohms so that seems fine. A few months back, I had a battery cable connector crack giving me a intermittent connection. That may of resulted in high enough resistance to melt the wire. Hopefully, nothing else was impacted.

For right now, I soldered a new ground wire. What confuses me is that the box is attached to the fender by two screws. Shouldn't this ground the box? I also smeared some dielectric grease (a.k.a. turn signal fluid) on the exposed components on the open side of the regulator. Good point about checking resistance.

I noticed a burnt wire on my voltage regulator. Can I just clean it up and tape it or would it be best to track down a replacement or investigate a cause of the melted insulation? They are $84 at Rock Auto. The braided hoses in the background are to my oil cooler in case you are wondering.

No, the new cover will have to wait a few months while I test the stock cover out and get an idea of what temperature it builds up to. Then I'll install the custom unit and try it with and without an air deflector. From what I was reading, setting a clutch type LSD to 80 percent lock as I did will build up more heat than a 100 percent lock. I don't plan on playing around with the lock unless I have to because adjusting the lock requires the removal of the differential and all the parts that are in the way of the differential.

The LSD is installed and seems to be working smoothly and quietly! Here's a summary of my experience installing the KAAZ DBN 2020 SQ in a Datsun 260z with an R180 differential: Installation Challenges and Solutions: Thread Buttons: The R180 differential uses side yoke bolts, while the DBN 2020 requires C-clips. Thread buttons are needed in the new LSD's side gears to adapt them to side bolts. Reusing the buttons from the original side gears might be more cost-effective and simpler than using KAAZ buttons (which lack splines). Ring Gear Compatibility: KAAZ R180 units are designed for 115mm ID ring gears. Early US Nissans might use a 110mm ring gear. Machining the 110mm to 115.3mm on a 4-jaw lathe is possible. Differential Case Clearance: The LSD will require grinding on the differential case for a proper fit. Use a Dremel or similar tool to remove minimal material, allowing the LSD to slide in end first then rotated for the ring gear to enter. The KAAZ technical support team was very helpful regarding cooling requirements, which was the subject of a separate question I posted on ClassicZCars.com. Hi Jeff, Thank you for the update. I am glad that all worked out. As for the oil, an external oil cooler will be a big plus for cooling and extra oil capacity. Under racing use, 80w90 GL5 will not last long. Generally speaking, one weekend of drifting or two weekends of road racing will kill the oil. We used to compete in Formula D and Time Attack series with our own Nissans back in the early days. I have tried many different brand oil both mineral based and synthetic based. At Formula Drift event, we had to change out the oil every day as the oil becomes like water after several runs. Once the oil is done, the diff will start making lots of chatter noise. For a daily driver and/or weekend spirited driving, the 80w90 will work fine. Oil change intervals will be every 4-5,000 miles or when the chatter noise starts to get loud. For this the Kaaz oil or the one from Torco works well. For racing use, I highly recommend the use of Torco RGO GL6 85w140. This oil will work well for most usages. If using Torco, please add their lsd friction modifier Type F. Heavier grade oil will last longer and more miles before change. After we switched to Torco, the gear oil lasted the whole race weekend. Kaaz unit works best with the mineral based gear oil. Synthetic oil will not harm the unit but the operation noise might get pretty loud. As for temperature, once it goes above mid 200F the oil will start to breakdown. Best Regards, Ray Nakadate Kaaz USA

I got the buttons on... I froze the buttons, heated the end gears with a torch, started the button with a brass mallet, and finally got out my 5-ton gear puller. I hope I never need to unbutton the LSD.

KAAZ tech replied that its a tight fit but I should be able to install the new buttons. In the mean time I found this thread: https://ratsun.net/topic/23766-k-r180-411-swap-need-help-pics/ that shows how to swap the buttons from an older R180 to a K R180. The article also references the same thread that Zed Head posted but includes more detailed information on how to separate the spider gears from the R180 to get to the buttons. Specifically, it shows where the roll pin is located that I need to drive out.

Thanks, I'm aware about the ring gear size issue because I had to machine mine on a lathe to get it to fit the LSD housing. I'm beginning to think the KAAZ LSD was designed for the Japanese market Z's.

Well, I'm still trying to get the LSD installed. The technician at KAAZ told me that I could purchase different "end gears" that are designed for screw type stub axels. He was traveling to Japan and would have them delivered to his hotel and bring them back to the States to ship to me. It would cost me about $350 but I really needed to get the Lsd installed so I agreed. A few days after he shipped them to me he e-mailed me again to say he discovered there was a threaded insert I could purchase for the existing end gears that would permit the use of the stock stub axels and I should send back (at KAAZ's expense) the new end gears I purchased. It took two weeks to get the threaded inserts and I tried to install them today. They don't fit. I can machine them down to make them fit but by then, it might be just as easy to machine my own from scratch. Lets see what KAAZ suggests now.

I hope to see you around Cleveland sometime. My car is out of commission right now waiting on a part for the LSD I'm installing. Jeff

Just wondering, why did you go to SU's and not stay with the Mikuni carburetors?

At first I thought CO was joking, but after reading the zclub thread, I'm not too sure.

I just found this on e-bay but my car doesn't have this flange. The splined axle is part of the universal yoke.

I finally was able to regain access to my garage to install the differential and ran into a (major) glitch. My axle ends will not attach to the new differential. Everything went fine, other than a smashed finger, until I tried to screw in the yoke fixing bolt. It would just spin. It was then that I realized that there was nothing to screw it into. I contacted KAAZ in the US and was told that the unit I purchased DAN2020 is designed for a C-clip stub. They do have a unit designed for a bolt-type stub like used in the early Skylines DAN2030. Dose anyone know where I can get a stub designed for C-clip installation or a drawing showing the exact location and dimensions of the C-clip slot so I can machine one on my existing stubs? Note that although KAAZ tech support identified the DAN2020 as being the correct model for my car, I purchased it from a vendor in Japan in early December so that potentially complicates any exchange.

I was just installing the differential with the original cover when the post man pulled up with a package. It came to a little more than expected at around $60 plus $23 S&H, and will need a lot of post-casting cleanup but for a first custom made part, I'm more than satisfied.

This is related to a project on another thread. I'm having a custom diff cover cast and need to tap it to accept the OEM plugs.

I wonder if it's actually 1/2-inch BSPT? They are almost interchangeable. If it is 1/2-inch NPT I should have one locally available.

Does anyone know the threading size for the differential drain and fill plugs. I tried to measure them and came up with 27x2.0 but apparently this was incorrect. My "Thread Detective" doesn't go this high.

Maybe a video camera or cell phone instead of putting yourself under the car. Or maybe find or borrow a set of "chassis ears". Unfortunately, you cannot attach them to rotating parts.

Great mod! Any chance you still have that CAD file? Its a shame to cut up the cross member just to get the two saddles. Great paint job! I've been tempted to get one of the inflatable paint booths for the back yard or create a booth in the garage like you did. For now, I'll stick with vinyl wrap.

Patcon, I've been going through the pages of the Lily build and have not spotted that part yet. Can you give me some direction on where that section of the build thread is? Jeff

That cross member supports the transverse links which gives me pause. It might be possible to create a standoff to shift the cross member 2-3 inches to the rear. The question is: Does the improvement in heat dissipation from the LSD worth the change in design of the vehicle's suspension supports? It looks like this R200 finned cover had the same issue and required modification as well: https://protunerz.com/products/protunerz-billet-r200-finned-differential-cover My son's partially dissembled Lotus is back under the Z again making this more difficult.