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JMortensen

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Everything posted by JMortensen

  1. JMortensen
    I signed up, then got into the Monroe autox which is 8 miles away and gets 14 runs, then it rained so I didn't go. What a disappointment.
  2. JMortensen
    That "put it back where it was" suggestion is a bad one even for a diff that has a crush sleeve. The R200 has no crush sleeve. The spec is RFT, I want to say it's something like 150 - 200 ft lbs. I always use red loctite on the nut the put my impact on 5 and hit it, empty the compressor until it fills, then hit it again. Never had any issues.
  3. JMortensen
  4. JMortensen
    The VIN is stamped on the firewall near the brake master. Above IIRC. You'll see it if you look for it.
  5. JMortensen
    Sounds like a turbo to me...
  6. JMortensen
    I bought a db meter yesterday. Going to do a couple runs up my private drive and see if I can't get where I need to be with the trapps. Also bought a head and neck restraint, so if this doesn't work I'll go do a track day and not have to worry about noise.
  7. JMortensen
    Agree on front camber, needs more if you're getting serious on the track. More caster would be nice too, but there are issues with tire/airdam clearance that pop up pretty quickly.
  8. JMortensen
    Front looks a lot better without the square headlights! Really brings it around! What are you going to do for lights?
  9. JMortensen
    My build thread is old and lots of broken links, but if you search just about any topic here, I'll have a thread on it. Tires are Formula Atlantic rears, so they are 15 x 13.75 Hoosier slicks on 15 x 14 wheels.
  10. JMortensen
    Having some issues with my mufflers. I was too loud last time, so I repacked with ceramic wool, then added supertrapps on the tips. The supertrapps are getting plugged by the wool. Took wool out, will replace with stainless scrubble, but that means that it won't reduce as much sound. I think I'm going to try the local autox in Monroe, WA as it's about 8 mi from my house and if they say I'm too loud it's not 4.5 hours driving to figure it out like Packwood. The Monroe autox is at Evergreen Speedway. It's a 1/4 mile oval track, and they run it like a tiny roval. No cone shagging, supposed to get 15 runs, but entries are limited to 70 people.
  11. JMortensen
    Just checked out your instagram. Looks very familiar, but you definitely did it better with your mesh wire. I taped over the wire frame that I made and it was a PITA to get the level right. Very nicely done! I'm also really impressed with your suspension uprights. So many of them are just thick steel flat uprights. Yours are much more sophisticated. I'm sure based on the rest of it that you have all your geometry and FEA calculated out. It looks like it's really done right. Again, very nicely done!
  12. JMortensen
    The bar ends wind up forward of the control arm holes. Shimming the bushings back from the uprights fixes this.
  13. JMortensen
    Not seeing anything that would cause a dead feeling in the wheel, but IMO that alignment is short on neg camber in front and heavy on toe in in the back for track use. I am not a fan of the 1 1/8" bars, would swap for 1" if I were you. You don't mention a rear bar, but with lowering springs I would run a 1" front and the ST rear bar that attaches to the uprights, and then shim it back 1/2 to 1", whatever fits best. Removing stiction from the sway bar bushing may make the suspension less stiff, but it also makes it smoother which means that the sway bar will resist in a constant way, rather than resist/release/resist/release, etc. When I built my suspension I went to great lengths to eliminate stiction in every way I could, as that makes the car more consistent and allows the suspension to work, and the wheels to follow the pavement better in bumpy turns.
  14. JMortensen
    Lots of us built our own, nothing wrong with that. I would suggest that you set up your arms so that you have a minimum amount of threads showing, so if you want the front arms to give you more camber, make them 1/2" longer or whatever with the rod end screwed all the way in, rather than making them stock length and then screwing the rod end out 1/2". I like the idea of using an inner tie rod for the TC rod. If you use a rod end the clevis you make for it will take up some room and you end up with a shorter TC rod which is not ideal. Not the end of the world, but not ideal. The TC rod does happen to be just about exactly the size to run a 5/8" die down it. I did that on a set, then ended up making something from scratch, but I can tell you that it does work.
  15. JMortensen
    I've got Adam's book. I actually ended up with a roll cage that was inspired by the balsa testing he did. Fig 12-14 on p90 if you're interested. I thought Staniforth's Competition Car Suspension had more info on how much to use and why, but YMMV. In any event, here is the thread where I showed what I measured when I moved the rack back and forward, used longer and shorter steer knuckles, etc:
  16. JMortensen
    My control arms are very slightly wider than stock, but yes, the main thing is the 15 x 14 wheels. I was surprised at the relative lack of difference that rack position had on Ackerman. When I set up the ps rack I had to move it forward. Prior to that I had a manual rack which I moved backwards as far as possible. Moving the stock rack back about 1.5" yielded another degree or two of angle change at full lock, so in the normal driving zone had almost no effect. Moving the new rack forward about 2" from stock basically turned it into a parallel steer car. As you say, the dynamic characteristics is the interesting variable. I don't know if there is a way to get this setup to have better Ackerman characteristics or not, and bumpsteer was pretty well managed before, so it will be interesting to see how that works out. I did have a friend with a 510 who went from stock knuckles to ones that were bent for Ackerman and the turn in on his autocross car was vastly improved. I'd like to have more Ackerman if possible, but I think it's really hard to do with the stock spindles. Cary has been super busy but is thinking he'll have something modeled in a couple weeks.
  17. JMortensen
    I'd get obliterated in EM, although I probably won't fare much better in XP. Ideally I'd like an open class where cars were divided on power to weight instead of displacement. Can always just run for time. It's more about making the car fast and improving my skills than winning a jacket.
  18. JMortensen
    Ooh, tuner challenge! That sounds like the ticket: open class racing. Would allow for better wing placement, paneled bottom, diffuser, etc...
  19. JMortensen
    XP
  20. JMortensen
    Add "both" to your poll. I am going to try for both and have no preference one way or the other. Only issue for me is I was over the sound limit last time, so I might have to spend my time screwing around with my supertrapps instead of socializing.
  21. JMortensen
    I had a machinist set up a cam for me and he checked a couple different springs and landed on Schneider's as having the best seat pressure for my .490/280 cam. The springs and retainers are easy to come by.
  22. JMortensen
    I checked it out and it's easy to see why the scrub is reduced. This actually looks like a pretty easy solution. I'm guessing there is a 12.2" Wilwood setup for an S13 that's readily available too. Still want to see what can be done with the dual ball joints, but thanks again, very helpful!
  23. JMortensen
    That's a really interesting option, thanks. How would one go about figuring out which spindles to try? Assuming some Nissan stuff would have the same bolt pattern so might be able to bolt the existing suspension up to it, thinking would need new front brakes, or at least new caliper brackets. I know Nissan used the Set 2 and Set 6 bearings up through the 300ZX, so that part might be the same if I stayed Nissan.
  24. JMortensen
    That's an interesting idea Dan, but I'd have several problems: 1. The cage is built to support the stock strut tower, and I'd be moving it over quite a ways. 2. Car would be way wider than it needs to be 3. Don't really want staggered tires. Always had issues getting the front end to hook up, and that's going to be exacerbated with narrower front tires 4. Tie rods will interfere with the wheels. Possible that a 16 x 10 or better, a 16 x 12 might work, but one of the reasons I went with the 15x14 is the easy availability of the FA tires 5. Doesn't really fix the scrub radius issue. Obviously would be less with a narrower rim, but might still be 4" if I couldn't do the 5.5" backspace. I like the dual ball joint thing because it could potentially be easy to implement, we'll see what the computers say. If the dual ball joint doesn't work and the car doesn't hook up with my new tires then I think I'll go one of two ways; either SLA or go to a 3" flare and run a 15 x 11 with the 275/35/15 Hoosier or 16 x 12 if I can find an appropriate slick to fit.
  25. JMortensen
    I told Cary I would get some more measurements. The rack on mine is 5.5" in front of the LCA pivot. Tried to measure the height of the inner and outer pivots but car is on jackstands now and I didn't want to take it off just for that measurement. Stock steer knuckles and rack moved forward and up and tie rods are using .9125" bumpsteer shim. Bumpsteer is minimized. Hopefully that gives you enough to go on. If not it will have to wait until next week most likely.
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