Scottie-GNZ Posted May 20, 2002 Share Posted May 20, 2002 My front wheels will be 17x8.5 with a 5.625" BS and a 5x4.75 bolt pattern. That means the wheels go out 2.875" from the hub mounting point. I mounted a Swastika 15x6 (which I assume has 0 offset), with 215/60-15 tires for trial fitting with various thickness of spacers. I maxed it out to 1.125" of spacers before I encountered interference with the fender where the valance/front dam bolts up and the problem is when the wheel/tire turns in. At this point, the wheel should be out 4.125" from the hub mount point. I figure I can overcome this interference since the tire I plan to use will have a slightly smaller diameter and if I limit the wheel to 3.75" out from the hub. Problem: This then requires a 4x4.5" to 5x4.75" adaptor/spacer only .825" thick. Far as I can tell, that is not possible after speaking with several manufacturers. Seems 1" is a stretch with 1.25 the minimum and some strongly recommend only a 2-piece design when changing the number of lugs. My Solution: Machine a 5.25" diameter, .825" thick, hub-centric disc with the 5x4.75" bolt pattern and lugs. It would also have 4 holes drilled an tapped to match the bolt pattern of the bolts that fixes the rotor to the hub. The original lugs would be removed from the hub and the hub trimmed enough to provide clearance for the 5x4.75" lugs in the disc. The threads for the 4 bolt holes in the hub would be cleaned out just enough to pass a longer bolt through it and be threaded into the disc which would be mounted over the hub. Where most adaptors are universal to fit a bolt pattern, this one is specific to a 240Z (or maybe 1st-gen) because it is hub-centric and bolts up over the hub. What do you think? Any reason why this could not be made out of aluminum? Please, no "why not go 5x4.5" suggestions. This is the first step in the front-end upgrade. I have not figured out how to solve the tire/perch clearance yet but will wait until I make the adaptor and see how much clearance I need. Also does not alter any plans for the brake upgrade. Here is a rough draft, repeat, rough . Quote Link to comment Share on other sites More sharing options...
Jeff Posted May 20, 2002 Share Posted May 20, 2002 Not that I'm an engineer, but I will give you my .02 worth. My first concern would be threading into the aluminum unless you are going to machine a pocket for the hub. Of course this makes the aluminum even thiner at that area. My second concern would be the shear induced during cornering on a relatively thin piece of aluminum. I would think the weak point would be where the hub stops and the aluminum cantilevers beyond that point. Again, no engineer just my opinion. Quote Link to comment Share on other sites More sharing options...
Pop N Wood Posted May 20, 2002 Share Posted May 20, 2002 Seems like you're really forging new ground here. And you're doing this on a car that runs 9's? Guess I would urge caution. I'll also second what Jeff said. Seems like a lot of force to be applying to such a thin piece of aluminum. Might be better off machining a whole new hub ($$$). Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted May 20, 2002 Share Posted May 20, 2002 BTW, I think the swastika wheels are 10mm offset, like the 6 spoke 14"x6" ones. Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted May 20, 2002 Author Share Posted May 20, 2002 10mm. Hmmm, that explains why the wheel/tire had less clearance with the perch than I thought it should. I will redo the calculations, but just looking for thoughts on the design. I suspected aluminum might not cut and that is why I asked. BTW, I have to use that wheel because that is what is already on the rear and chosen for its offset to fit the Vette IRS install. Here is a frontal view of the design to make it a little clearer. Do not have CAD so the crude PPT drawings will have to do for now. Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted May 20, 2002 Share Posted May 20, 2002 Just my $0.02 -- you definitely don't want to thread into aluminum unless you heli-coil it, and I'd still hesitate considering the application. You have to have it machined anyway, so use a good steel for the disc. Quote Link to comment Share on other sites More sharing options...
johnc Posted May 20, 2002 Share Posted May 20, 2002 Make it out of steel. Don't remove the threads from the stock wheel studs. That will weaken the fastener and create stress risers. Ream the holes in the hub for the wheel studs and use a standard Chevy 1/2" stud with a 1/2" shoulder. Quote Link to comment Share on other sites More sharing options...
Guest Thurem Posted May 21, 2002 Share Posted May 21, 2002 You're Mad, and why don't you just go to 5 on 4.5... Here, I just had to do that. I remember seeing a post a long time ago, which said that a Chevy hub would fit the bearings on the stock spindle. Who knows you might have to mix and match some bearings, ie. nissan inner race and chevy outer race. Remember its only a piece of metal. Thure PS Please note this is my 200'th post Quote Link to comment Share on other sites More sharing options...
pparaska Posted May 21, 2002 Share Posted May 21, 2002 Use some really nice high strength steel too! I like johnc's suggestion on the 1/2 Chevy lugs too! And thurem is correct, some of the (3rd gen?) F-body hubs will fit right onto the Nissan spindle. Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted May 21, 2002 Author Share Posted May 21, 2002 OK, aluminum is out . I redid the calculations and went out to trial fit for confirmation. A 13/16" stack of spacers provided the perfect spacing with the fender when turning in. What that translates into is the wheel coming out 3.42" from the hub. To match that spacing with the 17s I would need a spacer .543" thick. Since aluminum is out, .5 steel sounds on the money. DAW, I like your idea of no threads and a nut inside the rotor in case I do something funky later with the rotor/hat. 1/2" steel should be enough thickness for the lugs. OK, it is time to reveal where I am going with as it relates to brakes. I want to do the C4 12" brakes to match the 11.4" rears. Below are 2 shots of the C4 brakes on a F-body. If my adaptor can accomodate the 5x4.75 and the 4 holes for the hub, so can the C4 rotor. So, I plan to drill the C4 rotor for the additional 4 holes and position it like the stock rotor. Note that the hat is deeper and that would require a caliper bracket and spacers to position the caliper correctly. Now I need to find a kind C4 owner who can loan me a caliper and rotor. Grumpy, you listening? Do not be shy about telling me I am MAD. Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted May 21, 2002 Author Share Posted May 21, 2002 Unless I misunderstand what John is trying to say, the problem is that the 71 hub diameter is not wide for the 5x4.75 bolt pattern and it is not even perfectly round. I do not see a choice but having the Chevy lugs in the new adaptor. In addition, the Vette uses 12x1.5 lugs and I already have ARPs on the rear and plan the same on the front. Minor, but a clarification nonetheless. Remember that the early hub is completely different from the later ones. Quote Link to comment Share on other sites More sharing options...
johnc Posted May 21, 2002 Share Posted May 21, 2002 The knurle on the ARP Chevy studs is slightly larger (.580 vs .560???) than the hole in the Z front wheel hub. You have to ream the stud holes in the hub to press the new ARP Chevy studs in correctly. You also want a shoulder on these studs to keep the threads from acting as a mill on the spacer you're building. Also, carefully measure the hub centers before machining you're hub centric spacers. Nissan did not design the hubs for hub centric wheels so there may be some large variances in the casting. Quote Link to comment Share on other sites More sharing options...
Mike kZ Posted May 21, 2002 Share Posted May 21, 2002 Did you try the Corvette hub, bearings and all on your datsun spindle? I bet it fits! My '62 chevy drum hubs fit like it was made for it. Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted May 21, 2002 Author Share Posted May 21, 2002 John, one more time. Take a look at the pic below of a 71 hub and you will see that the 4.5" diameter of the lugs would actualy be on the edge of the 4 cutouts. Not possible to do the Chevy lugs on that hub. Remember, I am trying to to go from the Datsun 4x4.5 to a Chevy 5x4.75. I have no choice but to press the Chevy lugs in the adaptor. Mike, any luck getting those pics? SCCA, hope you do not mind me using one of your pics. Quote Link to comment Share on other sites More sharing options...
johnc Posted May 22, 2002 Share Posted May 22, 2002 OK, I get it. I was backwards. Sorry. Quote Link to comment Share on other sites More sharing options...
Mike kZ Posted May 22, 2002 Share Posted May 22, 2002 Originally posted by Scottie-GNZ: Mike, any luck getting those pics? Sorry Scottie I haven't had time to hook up my scanner. As soon as i do I'll send you some pics. Quote Link to comment Share on other sites More sharing options...
Mike kZ Posted May 24, 2002 Share Posted May 24, 2002 Here's your pic Scottie. If you look close there is a spacer between the hub and rotor. This is because of the hub's studs. Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted May 24, 2002 Author Share Posted May 24, 2002 THANK YOU!!! How does the caliper get mounted to the hub? Other than the spindle nut, are there any other attachment points on the hub? What brakes are those that you are using? Quote Link to comment Share on other sites More sharing options...
Mike kZ Posted May 24, 2002 Share Posted May 24, 2002 Originally posted by Scottie-GNZ:[QB]THANK YOU!!! How does the caliper get mounted to the hub? -It's a Toyota caliper and mounts in the stock location with stock bolts. Other than the spindle nut, are there any other attachment points on the hub? - No, but I had to drill out the cotter pin hole a bit so I could put one in there. What brakes are those that you are using? Stock rotors, and Toyota calipers. Soon I will try a Chevy front disc and some other caliper. Quote Link to comment Share on other sites More sharing options...
240Z Turbo Posted May 24, 2002 Share Posted May 24, 2002 Scottie, don't do it! Your car will explode because of all the american CRAP on it! HEHE! So, the 4140HT is cheap and I can do it for you....However, I think the chevy hub is preferable! Let me know! Quote Link to comment Share on other sites More sharing options...
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