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Adding info I was given from Keas on these transmissions. I was given permission to share. In an email I was told that only a slightly stronger spring could be used in the Pressure modifier valve. This goes against what other build info I have found online. I think the info on replacing the plastic thrust bearing and modifying the planetary to be very useful. I have seen alot of people in my searching having broken thrust bearings or planetary failures. I know this is an old thread but trying to put this info in places it can be found JATCO 4N71B Rebuild Modifications.pdf

Hello everyone. I am building a 1984 Maxima wagon (not a Z but has the same basic drivetrain.) I have turbo'ed the stock L24e and have a L28et sitting on the stand to put in. My car is auto and has the L4n71b transmission. I am in the process of rebuilding a 1984 300zx Turbo auto transmission for the car which is a 4n71b. Firstly there is very little info on the internet about these transmissions and half of it is wrong. In my searching for info on how to build the 300zx transmission up to handle power the name KEAS from Australia keeps popping up. They seem to have done alot with the jatco transmissions in the performance world. Well I emailed them and asked for pricing on a valve body This is where I was shocked. They sent me the instructions on where to drill the separator plate and then he sent me the info on building up the transmission itself and how to address the weak points. I asked if I could share and he said yes so putting the info on here to help future builders. What is interesting is that they don't modify any of the springs per the level 10 info and the shift kit the guy from austraila sells. See details in the thread below. Little hard to follow but i think you can understand. Jeff, The only Valve that could use a slightly Stronger Spring is the Pressure Modifier Valve. Over-do the strength of the Spring and extremely late or nil WOT Shifting will occur. The Weak Areas in order of Failure are: Intermediate Shaft Input Shaft Over Drive Sprag. We have Billet Piston/ Servo Sets but your not there yet. See attached PDF for transmission upgrades. Have fun. Paul. Wow thank you so much for that info. I have the stock modulator from the turbo 300zx. And I have ATP nx-2 modulator. Thats adjustable that is listed for the turbo cars. Not sure about the diaphragm thickness. With the separator plate do I need to do anything with the valves? The info I've seen online say to shim the pressure regulating valve 2.54mm and the pressure modifier valve the same or install a stiffer spring.(or pin it for very firm shifts. From the link below. https://www.mygen.com/users/dbruce/myz31/LevelTen_Performance_Automatic_Transmission_Install.htm At what point are the cast band pistons not viable and billet ones are needed? And yes the engine is a l28et from a 280zx turbo. Not sure if you ever got those in Australia but its the same l6 platform as the L24 from the 240zed etc. Jeff, I'll assume your Engine is Turbo Charged. The Valve Body (If it was from a Turbo Charged Vehicle) runs into Shifting issues around 13psi. And you cannot buy the Turbo Specific Modulator anymore. It contained a thicker diagram that lasted longer the NA items. I would fit a Full Manual Valve Body that has fixed Line Pressure. As a starting point- try modifying your Separator Plate as shown on the PDF Building a 1984 Maxima Wagon in the USA. Has a L28et from a 280zx turbo with a 4n71b from a 84 300zx turbo behind it. Planning on around 300 hp to the wheels Just replaced all the gaskets, seals, o-rings, clutches, steels, and bands set all clearances to factory spec. What valve body mods do you offer? Finding info in the states is hard and your name keeps popping up so I thought I would see what you offer and pricing. Thanks JATCO 4N71B Rebuild Modifications.pdf

No, i didn't buy them, the goal was to have them made at Volvo Power train as Penta(i'm Volvo Penta) have some of their product development there. but they are over there heads in work so no time for private stuff. I have contacted a guy that makes sequential gearboxes and other fun stuff to make them. /Christian

They are Spinwerkes series 82. Unfortunately they are no longer available. I bought them around 2007. 15x10 and weigh 12 lbs

@74_5.0L_Z what wheels are those?

I also posted about this on the Classic Zcar forum but forgot to update this one. Here is a link to that post: https://www.classiczcars.com/forums/topic/69530-77-280z-running-rich-at-idle-afm-screw-doesnt-work/#comments In short, I tracked the problem to a faulty AFM (Air Flow Meter). The carbon track inside the AFM looks fine but when hooking it up to a battery and measuring with a multi meter there was a break in the track. Unfortunately it’s not repairable and I couldn’t find a Datsun AFM in Europe or somebody that could repair or recreate the circuit board (the carbon resistive track part that is). This has lead me into a pretty undocumented part of the Datsun / Bosch EFI system that is the AFM. It’s pretty much just a voltage divider (brings down the battery voltage) and a potentiometer. However nobody makes a potentiometer I could jerry rig inside of the AFM to recreate the original signal. However in my goal to make the car run (not rich) again I found a possible solution. Why not just use a different AFM? I mean it’s basically just a generic Bosch / Denso AFM module (5 pin) with fuel cut off (which makes it a 7 pin). The only problem is that the Datsun’s use the earlier > 5V AFM otherwise u could just grab one from a BMW or Opel. I did find an Australian forum post that mentioned a Toyota AFM that was plug and play with some spring tension adjustment with a part number that (over here) came back to one from a 90’s Ford Probe / Mazda 626. The part number was F201 13 210 (197100-3420) for the record. As this AFM was only €25 at the local wrecker I got one as well. I will be testing this AFM over the weekend to see if it actually works in the Datsun and also works well. I did notice the Mazda AFM is much bigger then the stock one. Maybe that second hand 60mm throttle body I saw online might be an good upgrade as well if this AFM works.

Ok, well back from the EFI conversion posts, back to just regular fun stuff posts. I decided to try custom length spark plug wires again. I ordered a set of the wire "cranes" from Lonely Driver Company and then ordered a set of 8.5 wires form Amazon and installed them today. As the pics show, it made more of a difference than I thought.

5 years to finish, as if you don't have enough stress with this build. At least you got the greenlight for now. Maybe I missed it, but did you buy halfshafts from somewhere, what's the wait on them?

The two areas "1" are a great place to attach tow hooks.

My current issue is with leaking oil and coolant. My head gasket is leaking coolant - this is between cylinder 1 and 2 on the RH side. I can see the coolant right at the edge of the engine/cyl head. When I installed the new timing cover, my head gasket got torn at the top. I made a gasket and used some aerobic silicone. The oil is leaking a little on both sides. The plan is to remove the cylinder head, take it to the shop to get it reconditioned (new stem seals, check the springs etc), put a new set of ARP stud fasteners with an OEM gasket. The new gasket will also stop, hopefully, the leak at the top of the timing cover. I checked the prices on the Nissan head bolts - they are in the hundreds now. Not sure what happened. The MSA is basically recommending to go cheaper ARP route (which used to cost more in the past, now it is reverse).

I also decided to re-address the lean condition on hot restarts. When it happens, the fuel pressure would bounce around, 18 - 22 psi. The FPR is set to 37-38 psi (w/o vacuum), at idle normal psi is around 31-32 psi with the vacuum attached. The FPR is an Aeromotive unit. Started with the fuel pump's (Walbro 255) voltage. 1. My original design - battery -> circuit breaker -> microsquirt's fuel pump relay -> main relay -> 30AMP relay (Inertia switch) -> Fuel Pump All wiring is 14 gauge. The voltage delta between the battery's and the fuel pump's was 1.5 Volts! 2. Re-did the ground - dedicated negative to the back panel's ground point where the tail lights get grounded. The delta was 1.2 Volts. 3. Installed a dedicated FP relay in the engine bay (Tyco 75Amp, with a 25amp fuse), with direct run to the fuel pump. The microsquirt's relay provides a trigger on post 86, inertia switch (in cabin) - ground. The delta is 0.3 Volts. Here is a diagram: Another possible issue might be related to the pre-pump's G3 Fram's filter being too restrictive (40 micron). Installed a 100 micron pre-filter: The pump is very quiet. The hot restart ends up with 14-15 AFRs for about 40 seconds, then it scales back to my pre-configured 13.5 at idle. I don't see a lot of fuel pressure fluctuations any more. As a precaution I added a 1979's 'hair dryer' to cool my injectors. I found it at a junk yard. I am using a time relay board which is set for 15 minutes. When I park the car, I can engage it from inside. I will test it on a hot day:

Installed a set of OEM engine mounts. They are still available, the cheapest ones are shipped from Japan (ebay source), about $120 total. Originally, I figured I would save some money and ordered a $20 special for a pair + s&h. Then I found some posts on classiczcars about their poor fitment, SAE threads (not with the pair I purchased), misaligned locating pins etc. Here are some pictures for comparison. The center bolt is longer on the after market one: The locating pin is way off: The OEM mounts fit like a glove, no issues.

Adding n42 intake. $350 shipped in lower 48?

Just bought a L28et from a car with 90k on it. I saw a video of the car running but it wasn't building boost. But it idled well and tried to rev. Turbo is shot and hitting the housing on compressor and turbine side I took these off last night and have not cleaned them up and thought i would offer them up on here and see if i can get a decent price before I list them on ebay. Paying through Venmo is the best All parts are sold as is. 280zx turbo distributor, distributor shaft, cap and wires. As stated I saw videos of it running but I have not used it. Looks to be in good shape and the cap is newer and the plug wires seem to be pretty high quality and made in USA. $425 OBO Shipped in lower 48 Turbo AFM. Looks to be in ok shape. Has been opened and is missing the cover. I have not put a multi meter on it to test but the car ran to well for it not to work. Comes with the bracket $190 obo Shipped in lower 48 L28et Fuel rail injectors and Fuel pressure regulator. Appear to be stock injectors. I cycled them all with a battery and they sound good and do not sound gummy. Includes injector seals which are in really good serviceable shape. Not cracked that I can see. All pintle caps are present and the FPR holds pressure with my mighty-vac. $200 OBO Shipped in lower 48 Turbo manifold. In really good shape. Just as i took it off. All studs are good and heat shields are present. I believe this is the first time its been off and there was zero exhaust leaks on the turbo or the head side. $275. Plus shipping. I want to calculate this one as its so heavy. Turbo Actuator. Good used actuator. Tested it with my mighty-vac and it holds pressure. $50 OBO shipped in lower 48 J-Pipe Paint is ok but its in good shape. The TB rubber is very pliable. Turbo side is serviceable but stiffer. $80 shipped in lower 48 I have other things ill get listed as i get pictures. Turbo oil pan, sensors and control valves on intake manifold. thermo housings etc. Things i might be convinced to sell. freshly bead blasted N42 intake. Complete oil cooler from block adapter to cooler,

Honestly not sure yet on fittings. I’ve only done caliper swaps, this is the most comprehensive brake system overhaul I’ve done. Gonna see what I’ve got to work with and go from there, wish me luck 😅

Nice placement in your engine bay. It looks like you just ran a positive off the battery terminal (?) to your box and all the accessories are using the chassis for the negative side. It is B+ only. No ground. It connects to the + terminal of the battery. Accessaries draw fused power from the fuse box. Each accessary is grounded to the chassis.

Miles: Nice placement in your engine bay. It looks like you just ran a positive off the battery terminal (?) to your box and all the accessories are using the chassis for the negative side. As most of my accessories (radio, windows and A/C so far) are in the passenger compartment, I was planning to put my box on the passenger side firewall and probably run both positive and negative 10 ga. leads to it.

Luigi: I used a $70 "universal" power window kit that can be obtained on Amazon or eBay. A current Amazon vendor is JDMSPEED. This is quite similar to the SPAL that was marketed some years ago. What I found in my research was that several marketers offer the almost, if not, identical units on these shopping sites. As the units are all made in China - perhaps by the same manufacturer - this kind of makes sense. It's like every corner convenience store selling M&Ms. Earlier this year I started collaborating with Dave Irwin (Zs-ondabrain) to update and expand a thread he created in 2006 on the Classic Zcar Club website www.classiczcars.com). I decided to alter the wiring so that just two switches are used and the controls are mounted on the sides of the center console. The article has kind of stalled out as I went on to do other things on my car but I swear I'll get it done and posted there before year's end. In the meanwhile, here's a photo of the drive unit installed in the left door of my car. The drive unit is on the lower left and the "engagement gear" is on the right. It has plenty of power to work the window mechanism but, my goodness, you absolutely must have the window track alignment perfect or it binds up.

Hopefully you are converting to all SAE / AN brake fittings. It's a real pain to have a mix of metric and SAE. I routed my brake lines inside the cabin to get the brake lines away from heat. I'm running a Wilwood Tandem Master Cylinder (7/8" bore) and use a proportioning valve installed on the drive shaft tunnel.

I have been. And for those searching its nivlac57 on YouTube. I have a 84 maxima wagon and I measurd once when I had my engine out and it was to close to try. I am interested in yhe 5 cylinder though as it would fit under my hood.

Picked this up from local hot rod shop for my 240z SBC 350 project about 13 years ago. Circuits: Electric fan relay Fuel pump Radio and amplifier Power windows Summit Racing/parts store etc probably have this fuse box.

I found it just by digging around online. Wilwood makes the assembly, allows me to run two different sized master cylinders for front and back, and on top of that the horizontal bolt close to the firewall allows me to adjust brake bias between the cylinders, lots of adjustability. It comes with this cable so I can adjust the brake bias from inside the car. Yes, all new brake lines. I bought pre-bent hard lines and some distribution blocks. Once I get the rear suspension off, I’ll replace the lines, then figure out how to attach the cylinders, probably get some flexible stainless steel lines for that.

looks like i have to open my steering column next winter, i think i have play on lower splines, upper bearing might have also something going on. anyone has good link for that kind of operation on fresh memory?

Seppi72? what power window stuff / kit did you use?

I've used these....