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Everything posted by JMortensen

  1. I think you're missing out here, regardless of whether you do it diagonally or setting fronts even. Mine was really far out. I'd be shocked if fixing this didn't help.
  2. There are SO MANY other things that could affect it, that I think your results (and mine) aren't really meaningful for other people. The thing about the Miatas is that they have a tendency to lock up the LF tire under braking. Not sure that I've heard anyone say that about their Z. FWIW I learned a new trick the other day: when corner weighting, set the front weights equal, rather than setting the diagonals even. This is supposed to load the front tires more evenly under braking. Between setting the fronts equal and making the lines equal length, you MIGHT be able to tell the difference. Probably not... To me these are things that you do when you're building because it's theoretically better. The actual difference it makes is probably pretty minute.
  3. I didn't think the position of the T made a difference either, but since I was plumbing it anyway I went ahead and did it as evenly as I could.
  4. I read something on Miata forums about the length of the hard lines being different, and this contributing to their tendency to lock up the LF tire, so I tried to put the Ts in the lines right in the middle. But yeah, T the front lines and go to the front master, and T the rears and go to the rear master.
  5. Since you mentioned bumpstops, what kind of bumpstops are you going to run? They're actually a very important part of the suspension, and most people with Zs run hard, crude, polyurethane from Energy Suspension, which suck donkey balls. I would suggest if you don't already have them you look at some of the longer, more compressible ones like Koni or FatCat Motorsports sells. They act more like a spring than a piece whose only responsibility is to keep suspension parts from slamming together.
  6. I wouldn't think it would be a problem if you have a needle bearing in the top hat already, but since it obviously is, bearings on the springs should help.
  7. It's pretty common for the spring to wear on the coilover sleeves. The problem is worse when you use longer springs. The longer the spring, the more it deflects. Bearings under one or both ends of the springs are a good idea as they help the spring to compress with less friction and will allow the strut to rotate more freely. https://www.ebay.com/itm/Strange-S1409-Spring-Seat-Bearing-Kit-2-pack-Torrington/123588766568?hash=item1cc676eb68:g:SvYAAOSwNm5ZsbJl
  8. That doesn't look abnormal. This thread goes over a bunch of causes:
  9. The G Machine TC setup is better than running poly in front IMO. Still should run rubber on the back so that it moves freely. They do wear, and may need replacing every few years. I used to take them apart and inspect and grease them up every so often. This video on polyurethane bushings in a Miata is really really really good. If you understand how the bushing is supposed to work than you can reduce some of the problems you'll encounter with the poly bushings that you'll buy for a Z, main one being the poly is too wide and the center sleeve is too short on pretty much everything as it comes out of the box. You can fix with a belt sander. Also I'd suggest drilling and tapping the control arms and sway bar saddles for zerk fittings. You will have to drill a hole in the bushing as well, but this will allow the bushings to be greased during services and will cut down on friction a lot. Don't bother with the inside bushings on the rear control arms. The bushing saddles aren't tight enough and the grease won't get in between the bushing and the sleeve. Outers on rear lcas works, as does inners on front, and the saddles on the sway bars.
  10. FWIW, I had a brand new brake system with new calipers, hard lines, soft lines, and dual masters that wouldn't bleed. Tried by myself, with help, with a mity vac and couldn't get a good pedal. What finally worked for me was using a 60cc food syringe and putting the fluid in through the bleeders at the calipers. I think there was a bubble that just wouldn't come out of the masters no matter what I did, but pushing the fluid backwards dislodged it.
  11. Yes, the hoop can be welded to the surrounding sheet. I have some shear panels welded between the sides of the car just behind the door and the vertical part of the hoop, and a couple 4" wide tabs where I welded the map bar to the top of the hoop. I totally agree that this is the way to take care of the C (actually B since Z has no B pillar) pillar paint cracking. 20 years or so ago I had a friend who ripped the A pillar off of his 240 autoxing it. He fixed the A pillar and welded in a 4 point bar and added one 6" wide shear plate just on the top and that got rid of all the interior panel creaking when he would go into driveways.
  12. I can definitely relate to Michael. Mine took 12 years to drive, although I took a couple years off. My suggestion is if you really want a done up chassis that's caged and ready to race, buy someone else's race car and start from there. If it's a street car I'd focus on things that are easy to accomplish and don't get too hung up on perfection. Things like strut tower bars make a big difference on a 240. Look at Apex Engineering's K member front crossmember setups, bolt in and connects the front X member to the TC rod buckets. Another simple area to brace is from the end of the rocker panel to the upper frame rail. You can pull the front fenders, weld those tubes in, cut the little piece that separates the fender from the wheel well, and bolt the fender back on.
  13. The boxes are the same, it's the pedals that are different. If you got an automatic brake pedal should install right into your existing pedal box.
  14. In my limited experience when mechanical pumps fail they spray oil all over the engine compartment. Electric pump doesn't put heat in the fuel like mech pump does, if that matters. Had issues with vapor lock on the L6 way back when. I fixed by eliminating the stock mech pump and fuel rail. Not sure if SBC has that problem very often.
  15. I feel like I can handle tuning a carb if I have some track time and my wideband. I got my triple 44s to run pretty well. I was guessing on the carb and guessed wrong, but I am way more confident in my ability to troubleshoot a carb than troubleshoot EFI.
  16. I am... electronically challenged. I can cut and weld stuff together, but I can't wire a lamp.
  17. L33 5.3L Aluminum block 799 heads .581 220/224 112+2 with Demon 650. Dyno results: 337 whp, 334 tq. Looks like he grabbed the wrong run and so it shows 330. Take my word for it. Needless to say all the moves I did on the carb in preparation were WRONG. Catastrophically wrong, like it would barely make it through a pull wrong, check out the massive dip in the torque curve! I put bigger jets in it, then brought still bigger jets, we needed to go smaller on everything. Leaned it out, leaned it out some more, more leaning, more lean, then finally it put out the 337 number. It sounded like it had a miss at the start, and as we got further along it was running rougher and rougher. Suspect bad plugs or wires. Didn't have time to change them out, as he didn't have plugs and wires there. They thought this was the cause of the rough graph. A BMW came in and did a pull and theirs was smooth. While we were making jetting changes we started talking about running it 1:1 where primaries and secondaries open together. I had tried setting it up like that and it just fell on its face, but we made it work. I'm happy about that because I won't get into the secondaries as I'm midway through a corner. It's not dialed in but it's safe to race and I'm happy with the numbers, of course I have to wonder where it would be running on all cylinders...
  18. I don't think you'll get it done for $10K. For that amount you could replace the 305 with a crate SBC that makes a lot more power and upgrade the trans and diff. Probably run out of money before you get to suspension and brakes.
  19. Used to be the guys at Maximum Motorsports (high quality aftermarket Mustang suspension/chassis parts mfr over on Sacramento) pretty much ran the CPSCC and they did a really good job. They handled all the autocrosses at Santa Maria airport. Those were shut down before I moved away, so I used to autox at Marina airport near Laguna Seca, which was run by Dennis Hale (big 510 guy). I believe that autox is still going, and there are others at that venue too. My understanding is that there might be more autocrosses at Santa Maria again, so I'd look into that. There is also the roadster thing every year in Solvang. That might not be exactly what you're looking for, but might find more local Datsun guys that way. If you're into track days you can try the Alfa Romeo Club of So Cal or Porsche Owners Club or PCA. Since there is such a dearth of car stuff going on there, getting out to one of these events will probably bring you in contact with the people in the area. Could also try the vintage races at Laguna Seca. That always draws a crowd of Datsun people. I think they're there, you just need to find them.
  20. Porsche Owners Club does an autox in Lompoc from time to time and from what I hear my old roommate Larry Butler takes FTD with his 510 almost every time. When I lived in Los Osos there was a Cal Poly Sports Car Club and there were a few of us Datsun guys. Don't think it's still around though.
  21. All done and painted. As soon as it dries I'll put the seat in permanently. Anyone happen to know if the seatbelt holes are 7/16-20? I think they all are, but when I tried putting a bolt in there it wouldn't go. Could just be paint on the threads but wanted to verify before I ran a tap through them.
  22. Welding went pretty smoothly. One tip I'll pass along is don't try to beat the floor up against the subframe connecters. What worked much better was a jack with a piece of plywood. Just jacked the floor up to the mount and tacked it in. Had to jack the floor on both sides of the SFC. Then took the plywood and jack out and stitched it. Got in and I'm thinking that the seat is slightly turned towards the driver's side but not enough that I want to redo anything. Also because of the layback there is less footroom on pass side, which might be a good thing as it will make it easier for people to jam their feet against the floor to keep from flopping around over there. Tomorrow: Seat back brace.
  23. I am working on putting a passenger seat in my race car. Driver's side is on a slider and the mount on that side is totally different but thought I'd share how this non-adjustable pass side is going in. First thing was removal of the stock mount. I had done this on the driver's side 10 years ago or so and remembered it being a big PITA. I did not remember wrong. I really hate trying to get all the spot welds loose. I tried a spot weld cutter and ruined it after successfully cutting about 10 spot welds. Unfortunately there are a lot more than 10 spot welds holding the stock mounts in. After that I tried air saws and other tools, but finally ended up with the tool I hate (and use) the most: 4.5" angle grinder. I used a cutoff wheel and hacked the stock mounts out and ground down as much of what was left as I could. Pro tip: I had been using ear plugs but figured out I could use my new bluetooth over ear headphones to listen to music and podcasts, and I could hear my phone ringing and customers on my website chatting with me, etc. Huge upgrade. I cut the stock mounts out and stuck the seat on the brackets in the car to figure out where the seat mount would be fore/aft. Then I measured from the seam in the floor behind the seats to where the seat bracket would be. I drew a line on the floor where the rear of the rear mount tube would be, and another one 2" in front of that. I had already figured out that there was going to be 6 1/8" between the front and back tubes, so I measured another 6 1/8" and drew another line across and another one 2" in front of that. So now I've got 4 lines across the floor marking where the front and back of each tube would be. Then I cut long strips of 2" tall cardboard, and trimmed them to match the contour of the floor. I then traced them onto the 2x2 tubes and used an angle grinder with cutoff wheel to shape the ends of the tube. Getting the front and back templates lined up correctly is kind of a pain because the trans tunnel isn't straight, so line them up on the outside where they hit the rocker. and leave a little extra on and then grind to fit. On the driver's side I cut into the bottom of the mount tubes to clear the little hump in the middle of the floor. On this side I cut the hump in the floor. I think cutting the hump is easier. After the tubes were cut to shape and fit reasonably close to the contour of the floor, I welded in two 6 1/8" tubes to connect the two and spaced them to fit right where the subframe connectors are. Next I needed to locate the seat laterally. I put the mount in the car and set the seat on its brackets on top of the mount, and figured out where I wanted the seat, then drew lines on either side of the brackets. Knowing where the nuts needed to be to bolt the seat in, I cut square holes in the top of the tube. Then I cut 2 x 2 pieces of .100" sheet and welded nuts to them to bolt the seat brackets to. After that I bolted the 2x2 plates with nuts to the seat brackets and set them on top of the mount and tack welded them in place. I unbolted the seat and brackets and finished welding the plates in. Next I'll weld the top ends of the tube to the rocker and the trans tunnel. I'll stitch the two longitudinal tubes to the subframe connectors. I used a LOT of heat on the driver's side and melted through the floor to get good penetration into the SFCs. My floor was pretty bashed up when I got this car, so the floor doesn't fit perfectly on the bottom of the 2x2 tubing. Plan there is to beat the floor up to the tubing after the mounts are welded on the ends, then stitch across the front and back of the tubing to attach the tubes to the floor. That's today's project. The mount on the driver's side was as long as the slider for the seat, so more like 12". Like I said before, much different on that side.
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