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Everything posted by mtnickel

  1. Just need a decent set of oem bolts for my z31t axle swap. I’ve heard they are more like a press fit into the axles and wanting to make sure they’ll work with the adapters I sell.
  2. mtnickel

    Z31T axle swap CAN fit

    Hi guys, Just thought I'd finally post some of my findings here since this is ultimately the place where I learned everything there is to know about technical aspects of the Z-car. So i present, the making of a z31 adapter. I realize this has definitely been done before and I'm not claiming to be the originator, but I never saw any measurements, or calculations and started from scratch instead. The following may not flow very well as most of it is from the instruction guide I made, but I tried to quickly edit as best I could. Background So there’s been a lot of information going back and forth about whether Z31 turbo axles will fit in the S30 chassis. Companion flanges, cage flipping, and then even custom shorter axles to be swapped in…which work, which don’t? Do the axles bind? etc. I’m trying to dispel at least some of the rumors/hearsay. Here is what I’ve found on my early 260z (I haven’t measured on 240z, or 280z, but I have a suspicion that the pickup points and axle clearances are all the same). Stock Axles compared to Z31T I took a measurement of the length of the stock axles while on the car at ride height. I then compared that side by side to stock Z31T axles. It was quickly apparent that it was going to be very close. The driverside looked to have some room, but the passenger side was as long as the axle if not just slightly longer. Driverside: Passenger side (centering lip is very close...hard to tell from pic). The Adapter Requirements Once I saw these measurements, I knew that if Z31T axles were to work, the companion adapter needed to be as far out as possible. Hence we aimed to make the adapter so that it is flush with the stock outboard flange. Here's how it turned out: Test Fitting With the adapters welded up, we then threw them on the car to check fitment. The axles are actually at their tightest point in full droop. Many have stated that when the axles get parallel/straight, they are longest and can bind, thus changing spring rate, wearing diff bearings, etc. They absolutely are not tightest there. I took the springs out, fitted everything up and during testing binding occurred in the lowest 1-2” of travel. Moving the hub upwards resulted in more clearance. I believe this is due to 1 of 2 reasons The axle and control arm are not parallel. I think closer to full droop, the control arm is pulling the hub closer to the diff at a faster rate than axle is. (in picture, all lines are the same and the distance between the 2 line end points (simulating lower arm and axle) is kept the same. The dotted line is aprox where the strut might be. So at full droop, the strut pulls in faster and leaves more of the axle out to bind against the strut) When the axle is parallel, the cage ends are also square, but as they get more angular, the axle may actually get slightly longer. It’s the same reason when the box below couldn’t be removed between 2 fixed walls without it becoming longer first. Comparing the fit on both sides, we find the passenger side is the tighter fitting axle. With the OEMZ31T axles, technically the driverside would be ok without flipping the cage, but you may as well flip the cage since you’re having to do the passenger side anyways. The passenger side OEM axle binds up during the lower 2” of droop. It binds so much so that you can’t even get the axle in when the car is jacked up. Flipping the cage gave enough clearance to both get the axle in and have a little give. Once closer to ride height, the clearance increases further and even at full compression there is lots of clearance. ROCK AUTO axles: These axles use the tripod design of the 280zx Turbo axle I believe (or maybe NA 300zx as well, don’t quote me on this. All I know is its not the same design as the OEM Turbo Z31 axles. Because it’s a different design, there are actually no cages to flip, so nothing can be done to these axles to make them shorter. Thankfully they fit as is and are just that little bit shorter than the OEM axles. So, Don’t bother popping the grease cap, as you’ll just find nothing to flip. Cage Flipping Details The cage flipping saves about 3.5mm of clearance (a little over 1/8”) no more.See the space between the cage and the axle end. This is the total amount of clearance we gain. After the cage is flipped, the axle end becomes the longest point. 1) Put your axle in a vise. 2) Grab the cv end and raise and lower effectively hammering the cage into the grease cap. You don’t pry the cap out with tools, but rather use the internals of the axle to pop it out. Use care here, as the first one I did shot the cap off spraying grease all over my friend. Haha. 3) Slide the outer cv cage down as far as you can. Mine inverted the seal a bit and stayed down there. You want to have access to the cage and balls. 4) I taped up the CV to ensure that while I was wrestling to remove it, the balls wouldn’t go flying into the dirt and grime on my floor. In hindsight however, the balls are a fairly tight fit and won't come out without a little persuasion. I found that out when I ended up rebuilding the whole axle as I didn't like the consistency of the grease and realized I shouldn't have mixed so much redline synthetic grease with the stock stuff. Probably for the best. 5) Take off the C-clip 6) Slide the entire cage off the axle. It may be a little stuck, so do what you can to pop it off (small plastic mallet, etc). 7) Turn the cage assembly around, and reinstall…should look like picture on the right. (I also ground the axle down, but this is not needed and you risk ruining the hardened temper if you don’t do it slow). 😎 You may at this point repack the unit with grease (compatible) as best you can. I ended up grinding the end of the axle a little as I wasn't sure how much room I would need. Not necessary however and perhaps can risk ruining the surface hardening of the splines if you're not careful. Rockauto axles are a lot thinner too: Grinding Stub Axle For the low profile adapter to provide all the clearance we need, you actually need to grind the stock stub axle down a little. See the nub sticking out from the flange? It would dig into our grease cap if we didn’t grind it off, so grind it down till it’s flush with the flange (use a straightedge to check for high points). There should be plenty of the staked portion of the nut still to keep that nut tight. Flange Welding and Preparation We ran into an issue after welding up our first set of adapters; the square flange on the Datsun hub is actually not very concentric. That is, the square doesn’t run true to the center of the axle assembly. Therefore if you just slip the adapter onto the square flange as best you can and go from there you may end up with it rotating on a ‘wobble’. I think we had something like 0.040" of runout by centering the adapter on the square portion of the flange. So it takes a little time and thought to make the flange concentric with the rotational axis. A dial gauge is ideal, but you could get it pretty close if you're good with some calipers: The stock centering hole can be pretty rough so it's tough to get it dead nuts. Plus when you tack it can pull the flange to one side. I recommend to shim it with paper or even shim stock if you have it, prior to tacking. Also, if you tack with the 309, it has enough give that you can give it a few whacks with the hammer to shift it a few thou one way or another. We ended up making a few more sets and didn't like all the fiddling, so we made a cool jig that locates the flange on both the stock axle ring and the new flange ring. Plus it bolts down to keep it flat to avoid warping. I could probably rent this thing out to anyone doing the job provided the leave a deposit and pay for shipping and such: Welding The machinist friend who made these with me said if we are going to sell any of these things, people gotta Tig weld them. Whether or not that's essential, I don't know, but I'll take his advice. It at least assures the welder has some experience and will know how to handle welding to cast. (remember the stock companion flange is from a cast piece). He said to use 309 filler. After all is said and done, these axles can be used without worry. I'm not sure how deep the MM flanges are or any others for that matter, but I do know its a pretty tight fit even with grinding the stub and flipping the cage. Although more clearance is had when the car rests on it's weight, so success can vary. Here's a few more shots of when we made both the first set and a bigger batch. To machine the backside, we cut the profile into those blank set of aluminum jaws. Here's the test fit on the driverside with the cage flipped and the axle slightly ground down. You can see from the amount of clearance, I didn't need to grind the axle down: Here's additional shot of one customer who had old school guy MIG weld it. If you can mig like this, pre-heat and avoid cracks, keep the flange centered, and keep it flat (bolted down), then it would probably work too: Sorry this is such a jumble of info...hope some find it useful. Happy to answer any questions. Cheers, Mark
  3. mtnickel

    Z31T axle swap CAN fit

    I’ll try to get a FS post up soon.
  4. mtnickel

    Z31T axle swap CAN fit

    Correct. It’s close on passenger side but fits and can be installed even at full droop where it’s tightest. It would be quite tricky to Center the flanges with the flange in the car. You’d have to remove the stock flange to weld it properly. Ideal to have strut out too so you can rotate it and check for runout before welding.
  5. I make weld on adapters now that basically do not add any width to where the stock square companion flange sits. You even need to lightly grind the stub axle so it's flush with the companion flange. I ran both sides through their entire suspension travel. Contrary to popular belief, the axle is tightest and most likely to bind at full droop. Even with my adapters, both sides need the CV cages flipped to be safe. The adapters also work with the Rock auto reman z31 turbo axles, though they are not nearly as strong as the OE nissan ones. They in turn use the 280zx tripod style CV and there is no cage to be flipped. Luckily they are ever so slightly shorter and still work with the adapters. I'll try and get a for sale post or thread up one of these days. Can find me on DPAN. Mark
  6. mtnickel

    R200 mustache bar..

    i have an extra bushing kit (poly).
  7. Since this time, Pat1 actually started making the pans for the conversion. Send him a message. not sure if he's still doing it, but check. Mark
  8. mtnickel

    R230 companion flange adaptor

    forgive my ignorance. But lets say you find a way to mount the R230, which axles go between these flanges and the Diff?
  9. mtnickel


    are these the ones that go into the diff? or the outboard axles? Had no idea they are worth this much! I gotta sell my 2 sets I have kicking around.
  10. mtnickel

    Too many choices, HELP RB VS L28

    if you're willing to do a custom split pulse manifold and a high quality fast spooling turbo, you could do 400whp without much lag. Something like an efr7163 borg warner. Costs $$$ though.
  11. mtnickel

    1971 240z rb25det build thread

    Best to start a new thread for this as not to clutter up his build thread
  12. I ran mine for a few street seasons. No problems. I ran a nylon lock nut, and added a regular jam nut just to be safe. No problems.
  13. mtnickel

    1988 300zx turbo partout

  14. mtnickel

    NA-T with high MATs

    ya, without a functioning intercooler, you really shouldn't be running over 5-6psi like they came stock. even then, I'm not sure i'd be comfortable on a track day. Also, do you have alternator problems? was showing just barely 12v when shouldn't it be 13.5-14?
  15. mtnickel

    Has anyone dealt with Bill Brinkworth?

    I know he broke his arm very recently and hasn't been able to do much work at all...perhaps a little preoccupied with some shows for his car too. I gather with the Arm broken, things have really backed up. But whether that's a justifiable reason or not is up for debate. They're one off parts and can't really be had elsewhere. Sort of like commissioning a shop to do some custom work, timelines can get pushed back. It's not something he has sitting on the shelf ready to ship. That said, lack of communication is a big no-no. I'd hope he would at least respond with updated timelines or some status on your order within a couple business days at most. He's not the type to "rip you off" though, just not super prompt with timing. Good luck, and if I see him around the local meets, I'll let him know.
  16. mtnickel

    Rust free datsun 1978 280z worth?

    I can see paying that amount for a COMPLETELY rust free Z. The amount of time and annoyance of rust repairs really adds up. Especially if you have to pay a professional to fix it. Plus cars that are in that condition body wise are usually pretty good for the rest of the car...often complete, unmolested, etc. Seems like a steal if it's as good as it looks in the pics. Take an awl (pointy screw driver) and probe for rust from underneath. Check seams where floor pans meet firewall, rails, doglegs, and the infamous battery area.
  17. mtnickel

    Problems tuning my RB25?

    i'm pretty well versed in nistune tuning. The stock rb25 maps go way retarded up in the 96 range as a safety measure incase someone experiences boost spikes or tries to run too much boost. The stock ECU is also known to have a huge dead spot from 44-4800 where they pull timing near peak torque. Questions: 1) are you running stock injectors? 2) are you running stock MAF? 3) do you know what your peak "load" value is (like somewhere between 80 and 90?) 4) what have you done for knock sensor? did you stub it out with a resistor? The RB25 knock sensor used on the z32 ecu is too sensitive and leads to false readings and pulls lots of timing. 5) did you adjust the K-constant at all during first running. Ideally what you do is drive while datalogging and get the long-term fuel trims to be close to 0. 5b) are you using the Feature pack maps? if you send me your tune and any logs you have, i could have a look at any problems. email me for fastest response. it's my hybridz username @gmail.com
  18. In actuality, the likelihood of a real and relevant response on this is not too bad on this forum. Lots of long standing and active members here.
  19. mtnickel

    Silver 1977 Datsun 280Z Project

    Looks like you're making great progress! it's no small job removing the dash. Keep up the good work.
  20. Nice 7 year bump. Hopefully member still frequents. haha
  21. mtnickel

    RB25 Fuel Line Questions

    After having a brake line blow out near the back and 1 fuel line start leaking near the isolator when I was fiddling around, I'd say replace all the hardliners going back. Unless of course the car was in a really dry environment and doesn't have any other rust/corrosion, then they may be fine.
  22. mtnickel

    Quietest muffler for V8 Z?

    Ya. As per the videos again, the 2.5" they said was really really quiet. So a single 2.5" I can imagine would be really quiet (depending the design).
  23. mtnickel

    Quietest muffler for V8 Z?

    Good watch on exhaust size : power relationship. https://youtu.be/_PVXvHkr-Vs Makes me really rethink having just a SINGLE 2.25" axle back on my 300 odd HP subaru. But I too like it quiet. May have to look at trying the Dynomax VT as one member above mentioned. They are surely quiet, but can be a little "unnatural" sounding as the spring flapper opens and closes. Also a good watch on Cast vs short vs long tube headers: https://youtu.be/Y7_lSU3D0jw and while we're on the subject, this one on dented headers blew my mind. Don't be scared to take a mallet to anything https://youtu.be/azPKIjxmmdU
  24. Hi there, I know a lot of wiper stuff has been covered at length, but I was curious about how to seamlessly integrate a Honda motor into the stock Z and wanted to understand the wiring circuit entirely. One little tidbit has been missed in a lot of this stuff. From looking at the diagrams, what is interesting is that when the wipers are set to off, the polarity to the wiper motor is reversed. It then operates for a short time in reverse to fully park the wipers. It does this due to a little fact that the wipers will actually go lower when the motor is ran in reverse. I found this out on Zclub.net. Heres' the quoted tidbit: (reference: http://zclub.net/forum/showpost.php?s=7082a089822ad1081635656e790cb302&p=210942&postcount=9). Final parking of the wiper arms. This is the clever bit which took me a while to work out. When the wipers are switched off the DC motor reverses it’s direction due to circuitry controlled by a relay strapped on to the side of the motor (this relay is used at other times too in the wiper operation). The linkage is attached to the motor via a short arm an eccentric cam bearing and coil spring. During normal operation the eccentric cam is in a position which has the effect of shortening the linkage, when the motor reverses the coil spring tightens due to the direction of travel, grips the eccentric cam, rotates it through 180’ and lengthens the linkage thus parking the wipers lower down the screen – clever eh? That’s why when switching to the off position the wiper always does a wipe – it’s to ‘park’ the wipers low down the screen. Now the problem is that on most cars (your’s? mine was) this coil spring will be broken and so the wipers will not park fully! If you position the wiper to park low down then this will become part of it’s normal sweep and so the other end of the sweep will be short! On the internet sites I’ve looked at nobody understands the purpose of this broken spring and because the wipers work with it broken it’s overlooked. While I haven't inspected my spring yet, I will do so soon as well as check if it does indeed park lower. But now came the thought about whether I should upgrade to the Honda motor or not. My wipers work fine albeit a little slowly. I feel now I'd rather have a little slow working wiper, but have them park lower. I feel if I use the Honda motor, it would be guess work if the park lobes (internal contacts) are setup the same to allow the reverse park to happen. But since I fully understand the circuit now, I figured I'd throw in a definitive answer on the best way to use the 260z or 280z with the intermittent function (as well as park, and low and high). This diagram I found on here is correct for the hookup: It's from a 76' 280z. Not my diagram, but kudos to BackDoorZ on here. Here's the Wiper FSM from 74 260z: This diagram is annoyingly hard to follow since they label the wires by function instead of color. The 6 wires going into the motor in the diagram and their respective colors are: B (Battery?) - Blue/Red P (Park?) - Yellow 2 (?) - Blue/White (Yellow/Green on 77-78 280z) E (earth) - Black H (High) - Blue/Yellow L (Low) - Blue - (Yellow/Blue on 77-78 280z) As a helper I believe the S and M switch is the internal lobe contacts in the stock wiper motor. S possibly meaning "stopped" and M "moving". Some notes: The middle part of the switch shows that if the switch is in 'int'/low/high, then it sends ground down the 2 wire. This energizes a relay in the wiper motor that sets the polarity so that it's 12v on top and then gets ground for either the low or high speed windings out the bottom. Tricky part is that if you switch to the off position mid stroke, then the power to the relay is cut mid stroke, so how does it keep 12v on the top of the motor. Well, when it's mid stroke, the S/M wiper will be on M and connect ground to the P wire. But it also lets current flow throw the diode to ground (in the wiper motor) keeping that relay energized till the stroke is done. So now it's finished it's default power stroke. When it gets back to the S wiper, it will invert the power to the top of the motor (you can see the top of the motor connected directly to E (earth). If you Trace the L wire back through, you can it goes back through 3, then into the box, then out P and ultimately connects back to 12v causing the motor to turn in reverse for a given period. I take it the specific phasing and size of the low will determine how much it actually rotates back. Here's the Honda (1997 accord, though I believe all the colors are the same): Putting these 2 together is a little tricky, but let me explain why BackDoorZ's diagram above works. He notes in his post that the Blue/white wire is never hooked up to anything. This is because it's sole purpose is to invert the power to the stock motor. The obvious: Honda - datsun - function Green/black - blue/red - this is constant 12v power. Basically always send power to one side of the motor. Black - black - this is always ground Blue - Blue - low speed wire. blue/yellow - blue/yellow - high speed wire. Honda's blue/white wire basically outputs 12v when the wiper is parked, and it outputs ground when it's mid stroke. By hooking this up to the yellow wire you get the intermittent and park to work. Looking at the 'int' diagram for the datsun, observe the 2 pole to the left of the capacitors (C1, C2). When the intermittent box actuates, it basically connects ground (E) up to M, which if you trace it back through connects to the low speed side. It probably only does this for a short moment, but enough to get the wiper into motion. But when the int box kicks off, it basically connects the low speed wire up to the P (the Yellow wire). Connecting this to the honda blue/white wire assures that you will again provide ground to the low speed wire till the wiper parks. I know that is really wordy, but the OCD in me wanted to get all these diagrams out there for those to see why it works or to troubleshoot issues. Can help with understanding why your stock circuit is acting up as well. ps. if you want to understand how the pie piece works on the honda diagram, assume the large part of the pie rotates and it is ground, the left small pie piece is 12v and is stationary, and the middle contact connects rides on whichever one is below it.
  25. not sure about the RB20 trans, but the RB25 requires a Navara/D21/Nissan hardbody truck sender. Depending your ratio, you can swap the RB20 skyline gear onto it with a little fab work. Details are on this site. Good luck with the build! I love my RB-Z and will never let it go