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JMortensen last won the day on June 3

JMortensen had the most liked content!

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About JMortensen

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  1. I did a quick check, and the stock front rotor is 10.6, so you'd want to get as close to that diameter as possible, since you can run up to the same diameter rotor. The early ZX is 10.5, later ZX is 10.2 according to rockauto.com. If you're going to make your caliper brackets, I'd use an early rotor and a late caliper. Or if possible find a rotor with a less deep hat. Early ZX has really deep one, the rotor is probably 3" back from the axle flange. Also re: drilled rotors. I pushed the piston through that brake pad with drilled rotors. I was at the track and needed to drive home, so I went to the local parts store, bought their shittiest pad, slapped it on and drove home. Changed them before the next race, but never even surfaced the rotors and there were no cracks at all between the holes. I worked on Porsches at that time and we routinely replaced rotors when the cracks were nearing the next cross drilled hole, but mine never cracked at all, front or rear, after lots of abuse. I will say that they make a weird buzzing noise when you get them hot. My explanation is the heated air is being released from the holes as the rotor turns past the brake pads, successively venting each little hole along the way. Not a problem, but it's kinda strange. The bigger issue is that you're taking away material. I guess the idea is that the cross drilling helps to cool the rotor, but more mass means it can absorb more heat, so ??? If you're running stock brakes in front I'd suggest a couple of 3" vents per side. Katman, who prepped a lot of ITS cars, posted about using a soup can with a slot in it to get air to the outside of the rotor, and warned against cooling only the inside. You might be able to search his threads to find. Probably close to 20 years ago now.
  2. Totally agree with this. Also, the early 79-81 ZX rear disc is not an upgrade in stopping power over the drums. It is possible to get enough rear braking with the early ZX and the stock front calipers, but any front upgrade will overwhelm the rears. I had Toyota fronts and the early ZX and couldn't get enough rear braking, eventually put the stock front calipers back on and was able to dial it in, but then I would boil the brake fluid all the time. Got to the point where I no longer got an adrenaline rush when the pedal went to the floor. That's a bad sign LOL. Also got the fronts so hot the brake pad lining just abandoned ship and a punched a hole through the backing plate. Rears had pad material coming off in chunks. To my discredit though, I was trying to run Porterfield's R4S street pad. Not a good idea... I never tried the 82-83 rear brakes so I can't tell you if they're any better. Definitely lighter, those early calipers are HEAVY and the pads are TINY. I would suggest looking at what other EP drivers are doing for brakes. Greg Ira is the 3x national champ. See if he has any recommendations for you. If you could use the ZX rotor and change out the caliper that might help. I don't think the heat capacity is as much of an issue in the rear, but the lack of clamping and pad surface area certainly is.
  3. No comment on those specific products, but I ran heims joints except for stock ball joints on my car for 40K miles, a couple seasons of autox, and a handful of track days and they didn't wear out and I didn't find them too harsh. I took my dad for a ride when he was about 70 and his comment when he got out was how comfy the Recaro seat was. I had 200/250 springs and ran Illuminas on 1 or 2 on the street.
  4. Don't remember a hole there. There are some oval drain holes in the bottom. That's not going to hurt anything, I'd leave it alone, but filling won't hurt anything either.
  5. Why did I think we were talking 280ZX? Sorry about that. Looks like a 280Z, there isn't enough room to move the strut back very far before the spring hits sheet metal, maybe an inch. You could cut the whole strut tower off of the upper frame rail and move it back, but that's a hell of a big job, and you better tie it all together well because it's a highly loaded part of the chassis. It's a lot easier just to run an adjustable TC rod. You can completely solve the LCA binding problem by running monoballs or rod ends on the front LCA. The next issue is that the tire will hit the front fenders or the airdam if you have one. Can trim for clearance. I haven't looked at it for a long time, but I seem to recall people getting into the 8 degrees range on race cars with adjustable TCs, and 5 degrees is easy. Caster made a huge difference on my Z, one of the best mods I did back when I was daily driving and autoxing every month.
  6. If you go to coilovers you can run a much smaller 2.5 ID spring, and then you can move the strut top back within the existing tower. This is not something we can do with the S30, but the S130 has much bigger strut tops, so more room to play. They do it all the time on Mustangs, so it's a known solution. I haven't seen a double adjustable plate for a 280ZX, but anything that has the adjustments and is generic enough should work. Might be able to just use the Mustang parts, just need adapter bushings to fit whatever struts you're running: https://www.maximummotorsports.com/Mustang-Caster-Camber-Plates-1990-1993-P254.aspx Could probably use these 510 plates from DP and cut the hole to the rear to add caster if you prefer: https://www.dpracing.co/datsun-510-front-suspension-1
  7. Going to require a different filler tube though. If the 260 filler tube is available it would probably go in easier, I'm guessing.
  8. https://www.ebay.com.au/itm/1955-1956-1957-CHEVY-GAS-TANK-FILLER-NECK-CHECK-VALVE-KIT-USA-MADE/133336309996?hash=item1f0b76a0ec:g:IxgAAOSwcB1eSbM0&frcectupt=true This ebay listing is from Australia, but says the product is made in USA.
  9. I wonder if you could use a simple flap under the cap, like they do on fuel cells. I haven't seen a one way valve in the filler neck, if that exists that would be another option. I guess the filler hoses are all getting rock hard at this point. 20 years ago I had to remove my original with a hammer and chisel. LOL If you can still get a new one could measure and see if there is a one way valve for a 2.5" or 3" or whatever diameter hose it is.
  10. Richard's offhand mention got my wheels turning too. DCT looks doable for about $5K all in...
  11. That noise was entirely 3rd gear related? Seemed to be happening regardless of gear. I had a similar one on my car, could only hear on decel. Turned out my driveshaft AND CV bolts had loosened. I safety wired the CVs and double nutted the driveshaft and haven't heard it since, but I'm just autocrossing, so not nearly as much chance to hear things like that. Can you add more hood vents? Under hood air looks like a problem for you. 167 mph on Conrod. Very impressive, and agree with Richard, nice job resisting the lift at the kink! In the sim-racing world, it's a toss up for me between Nordschleife and Bathurst for me. My two favorites. Hope to some day get there and drive something, probably a rental Kia around it. Inspiring stuff, thanks for sharing.
  12. There is quite a bit of weight in the tubes. When I did mine the SCCA said they were going to change the tubing requirements, and at the time they had 1.5 x .120 and 1.75 x .090. I went with 1.75 x .120 anticipating a change to a heavier tube, but when they released the rules, they had gone the other way and the requirement was 1.5 x .095. I haven't gone through how much weight I would have saved with 1.5 x .095, but man, I wish I had gone that way. Probably 50 lbs added, a lot of it way up high. Not good. EDIT--I did do the 6 point main part of the cage in 1.75 x .120, then I did all of the other stiffening tubes in 1.625 x .065.
  13. I'm not a vintage racer, but I believe they're allowed to run the way they were in the past. They used to allow cages without the tubes welded all the way around too, and I think those cars are still allowed. BTW I did the same on the seat mount, welded to the SFCs. Used to be a video of a Honda drag racer that went sideways into the wall and the AL seat folded in half, video was pretty scary looking. I get that some seats don't need it, but I like the idea regardless of whether it's required.
  14. Have you seen the Flying Miata butterfly brace? That's a good place to start. Hard to do on a Z with the exhaust hanging down. Reason number 486 for going with sidepipes. If I ever get around to doing a paneled floor, I'll incorporate some sort of bracing into the top side. For protecting the driver really needs to extend all the way to the rockers.
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