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mtnickel

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Everything posted by mtnickel

  1. mtnickel

    Z31T axle swap CAN fit

    Messaged. Let me know. Previous user waiting to ship. You’re next.
  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

    We’ll have to figure out whether it’s the SS axles or some other discrepancy maybe between 240 and 280 models. One thing I overlooked is that my rear struts are sectioned about 1”, so my “full droop” may not be as long as others. But I thought the 260/280z sat higher with a bigger isolator which would somewhat negate that. I’ll see how other regular nonVlsd guys fare. So far no other complaints. Thanks for the post!
  4. mtnickel

    Z31T axle swap CAN fit

    I believe I had a FS post started if you search the classifieds. They are available
  5. mtnickel

    What about EFR 7064? Its one sale...

    So you run the 6258 on the L28ET? i'm debating between the 6758 and 7163 on my RB25. From the numbers, it looks like the 6758 can get me pretty close to my 370whp goal (little over 425 hp). Plus it will spool quicker than the 7163, however it will probably be a power band that dies off in the higher RPM. Additionally, there is something to be said about turbine efficiency...the 7163 will probably make more power at a better pressure ratio with less back pressure. Decisions decisions.
  6. mtnickel

    VOLVO 850 FAN INSTALL

    I ran the same Volvo Fan. Built a shroud from fibreglass...sort of a fun project. If you can find a parts volvo, The relay system on it is very robust; comes with nice connectors already and also provision for high and low speed fan control.
  7. mtnickel

    Which CV kits are best for an R200 240Z?

    Ya, weld on adapters aren’t an ideal solution, and we are at the mercy of stock stubs. But all in all, it was the cheapest decent solution I could come up with. Newzed With my adapters, it’s still a close fit at full droop and I would recommend flipping the cages. But that only takes about 10 minutes to do. Saves the 3.5 odd mm. And they are maybe a little more outboard of Joe’s since they even require to grind the stub axle down a shade. Joe may have been able to make his even more outward provided you could trim more of the stub off. You’d lose the staked portion, but the newer ZX nut is a locking nut that would alleviate it.
  8. mtnickel

    Which CV kits are best for an R200 240Z?

    Great questions. We found out the hard way that the square flange isn’t concentric. It’s a rough cast and can be off almost 1mm. The z31t axle centers on the locating ring of the adapter. The adapter sits flat to the machined face of the stock flange. That takes care of 2 orientations. To weld the adapter on correctly we made the square a touch small. That way you can strategically grind the edges of your square flange to be equal from the Center locating ring. We recommend using a dial indicator to verify you get it reasonably close. If it’s a little big, you can use feeler gauges, shim stock, or even paper as stock to shim it true before tacking. Or you can rent the jig we made to locate it. Haha both options shown in pics
  9. mtnickel

    Which CV kits are best for an R200 240Z?

    Here’s what our slim welded adapter looks like. Basically converts the stock flange to a larger one. Stock z31t axles fit like this. 4 fasteners a side = winning.
  10. mtnickel

    Which CV kits are best for an R200 240Z?

    If you're resourceful enough to find some original Z31T axles, I still believe that's the nicest swap. The main benefit is that there are no fasteners on the diff end...the axle plugs right into the diff. It's just a matter of getting a companion flange on the outboard side to bolt it in. I'm biased perhaps as I sell weld on adapters...but adapters are $195, used Z31T cv's will run you 250-280, and welding the adapter in probably another $100 if you can't do it. So $550 all in. They are known to be very strong too. See my post in the Drivetrain section. Encouraging that Z garage has made a better set. I don't see how theirs don't have adapters though? Still looks like 930 style with adapter...maybe they weld them? I bought the wolf creek setup first hoping it was just a bolt it, but like Z garage found, the CV's they use are terribly sloppy. I then bought true Porsche 930 CV's, but the idea of 20 fasters for axles didn't appeal to me, so I figured out the Z31T setup.
  11. Had a post about the design process and checking of clearance in the Drivetrain section. Now here's the sale post of the adapters I've made several sets of. Quick Description: Z31T weld on adapter Flanges to fit Z31T CV axles into S30 chassis with the use of an R200. Long Description: They weld onto the outboard axle flange to provide a bolt pattern that will fit Z31 Turbo axles. The axles are NLA but you can find them on forums, craigslist, car-part.com, ebay, etc. They are a very strong axle. It is for an R200 diff, not stock R180. Rockauto has recently has some new style axles. The CV type is tripod which is a little weaker and the axle shaft diameter is fair bit smaller. no idea how much power they will support. 1) They are weld on style. They must be welded by someone with a little experience since you're welding to the stock CAST flange. They also must be bolted down if you want the flange to remain flat. They also must be centered into the square relief. The Square flange IS NOT concentric to the rotational axis and it must be shimmed and positioned correctly so that there is minimal runout. 2) They require grinding the stub axle nut and shaft between 1/16-1/8" depending on if its 240 or 280 style. Basically enough so that the flange is flat. 3) They still require flipping the cages inside the CV. I've measured that on the Driverside it would be fine (only 2.5mm of clearance) without, but I'd do it anyways. Passenger side is tighter and needs it. 4). Material is mild steel. Paint or powdercoat (if you remove the stock flange to weld) at your own will to prevent corrosion. I've got a PDF of the instructions for install attached. Sets are $195 USD shipped. I have 1 set that is already welded to the 260z/280z companion flange. It's not painted but perfectly centered and has quality tig weld on it. $295USD shipped. Z31 Turbo CV axle Conversion-v3.pdf
  12. You could weld em shut if you want. To machine that would make them thicker and add a lot of machine time. For cosmetic reasons only.
  13. mtnickel

    Electric Power Steering Information Compiled

    Much appreciated for this info! I have been mulling this swap over. I think i can live without (or rather maybe not live) the collapsable column and plan on a simple install. Due to size and ease of availability, I was going to try the Yaris non-abs with VSS signal. First I may try just using a pulse generator to vary the VSS signal to see if i can find a static point that works well...or alternatively, I've bought a GPS speed sensor on ebay and will try to run that (may need to scale the speed up or down with either an arduino or 555 timer or something). My only fear is the load with 205 sticky tires and a heavy turbo engine swap. But anything is better than nothing. Look forward to the updates!
  14. I’d be interested in one of these. I also commend you on your ambition. As has been mentioned however, is that I think the welding and working with the welder, planning assembly and order of welds will be key. Have to remember this will be HOURS of welding. Plus machining both flanges. It’s a lot of work. Hard to keep cost down. The CX racing one is even $600us and they hardly pay for labour. Haha
  15. mtnickel

    Ford Super 8.8 irs swap thread. Rear brakes too

    All in the name of weight and cost savings. Heck, my 93 and 97 accords had double wishbone front and rear!
  16. mtnickel

    Ford Super 8.8 irs swap thread. Rear brakes too

    Ya, it’s all a bit of a mess. The original poster does seem to have a pretty good handle on it I gather. The inner pivots needing to match only holds true when the spindle is held static. But like he said, since the tie rod moved outboard it’s ok that the inner pivot moves as well since our main goal is to have the control arm and tie rod be parallel and roughly the same length. Exciting stuff. If I wasn’t so deep into my setup, I’d be exploring this a whole lot. Brake, suspension, cheap and readily accessible beefy diffs. Lots of pluses.
  17. mtnickel

    Ford Super 8.8 irs swap thread. Rear brakes too

    makes sense. These are, I believe, the different ways Ackerman changes. But as I said before, since wheelbase and track width are both decreasing, then Ackerman is Probably still in a reasonable range.
  18. mtnickel

    Ford Super 8.8 irs swap thread. Rear brakes too

    I was under the impression ackerman is based not on the distance from ball joint to tie rod, but rather the angle between the spindle (wheel axis) and steering arm. Additionally, to correct bump steering it's the inner pivot (ie inner control arm mount point) that has to match the inner tie rod joint. The outboard tie rod mount will mainly dictate how long of a tie rod you need.
  19. mtnickel

    Ford Super 8.8 irs swap thread. Rear brakes too

    Ah, I failed to remember that track width has also decreased, so if the track width and wheelbase descrease at close to the same amount, then the ackerman probably is pretty close. My bad. But good food for thought!
  20. mtnickel

    Ford Super 8.8 irs swap thread. Rear brakes too

    I wasn't talking about track width. The mustang has a wheel base (distance from front wheels to back) of 107.1" The 240z has a wheelbase of 90.7". The ackerman usually changes depending on the wheelbase. It might be a little off...but perhaps won't be an issue for most driving situations, but could cause an increase in scrubbing in low speed parking lot maneuvers and tighter low speed corners.
  21. welded set pending.
  22. 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.
  23. mtnickel

    Ford Super 8.8 irs swap thread. Rear brakes too

    True enough. Going to all the work, may as well gain all the other benefits for not much more. So the ackerman is the same too? Interesting considering the different wheel base. Steering ratio not changed either (ie steering arm is same length?)
  24. mtnickel

    Ford Super 8.8 irs swap thread. Rear brakes too

    Did you look into the effects on the scrub radius of using the front knuckles? Also, wonder if we could also figure out just a diff swap option: 1) use the cradle you're making 2) Perhaps we could have mustang axle just shortened and resplined on one end for the 930 CV. Then 930 to stock stock datsun companions are readily available. https://zcardepot.com/billet-aluminum-axle-adaptors-930-cv-240z-260z-280z.html 3) Driveshaft adapter as you've shown.
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