Everything posted by Captain Obvious
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Top Dead Center
In theory, the pistons only ever completely come to a stop exactly at TDC and BDC. However, in reality, it'll stop for the entire time you are taking up the bearing clearances. Hopefully that isn't very long...
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KONI Sports for Classic Z's
I'm no suspension expert and I'm going to go out a little too far on my limb here, but I don't think that's quite right. I believe the force exerted by the gas is proportional to the diameter of the strut shaft where it exits the cartridge, not the diameter of the internal piston. I don't think the diameter of the internal piston has any effect in this case. My understanding goes like this: The more the strut is compressed, the more of the shaft is INSIDE the strut. The additional volume of the shaft (A*L) inside the strut assy will displace oil inside the body. That volume of oil displaced will compress the gas inside the strut, but only by the amount of VOLUME of the strut rod which has entered the strut. The internal gas pressure is static across the internal piston. At least that's how it appears to me way out on my limb here.
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Silvermine Motors Electric Power Steering System
Well I'm glad that it turned out to be such a non-problem, but is it really OK for there to be that much play in the rack position inside the bushing? I thought the whole point that the bushing on the right left side of the rack is NOT round is to prevent exactly that kind of rotation? What's to prevent it from rotating back to where it was before? I guess I just never loosened mine up and collected all the tolerance in one direction...
- 240z - fabbing new front rails
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Patton Machine Fuel Injection
My original temp sensor was looking quite ragged around the edges, so when I adapted that 260 thermostat housing to my 280, I also took the opportunity to replace the temp sensor with a new one. I bought a new sensor off rock auto and to confirm that it had the same characteristics, I compared it to my original on the stove in a pot of water. I just wanted to be sure. They were slightly different, but well within the accuracy limits laid out in the FSM. Here's my "test rig": And here's a summary of the results:
- 240z - fabbing new front rails
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Patton Machine Fuel Injection
The middle line is the "typical" (perfect) measurement. and the outside lines are range "limits". So if you are designing a system, you should probably aim for typical (halfway between max and min), but since any sensor you might purchase could be anywhere between those two points, you have to either characterize the sensor and trim the system for that sensor, or your system needs to be able to work acceptably with any sensor within that range. Those sensors are RTD's and they are available with different curves. And looking at the data for that GM sensor, it looks like it's a different curve. Doesn't the EFI system you are putting in place already expect a specific certain sensor curve? Is there any info in the documentation about what it's expecting? And lastly, here's a chart I put together for the 280 coolant temp sensor. I didn't look into it, but I would assume the ZX is the same?
- 240z - fabbing new front rails
- 240z - fabbing new front rails
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240z - fabbing new front rails
Well, it's not like it doesn't work at all, but I didn't like the results. I tried it because I had the TIG (which requires 100% argon), and my welding gas guy told me I could share a tank between the two machines and run straight up argon on both. I found the weld beads noticeably tall and lower penetration. So now I unfortunately have two bottles. One tank 100% argon for the TIG and another tank of 75% argon 25% CO2 for the MIG. I did some digging online and the general consensus is that my results were typical. Here's a pic from someone else that describes what happens Less heat into the workpiece so you end up with a tall narrow bead and lower penetration: Here's some web pages with some good info: https://welditu.com/welders/mig/tips-mig/mig-welding-with-100-argon/ http://shdesigns.org/Welding/gasmix.shtml All that said, I've read on the internets that if you surround the welded area with strong magnets, the oxygen atoms are pushed away hence no need for gas. I'm not sure that would work for 100% argon though since the argon is inert.
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Which engine for a 77’ 280z
And Gone!!
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Silvermine Motors Electric Power Steering System
In theory, the rack should not be able to rotate at all. The bushings should establish the correct position and lock the rack into place. That said, I'm guessing there's some squirm that you could probably take advantage of and it sure does look like the angle at that bottom U-joint is off some. It's definitely different than the 240 pics you posted above. Any chance you got the non-round side bushing in upside down or wrong somehow? Is that even possible? Here's your 280 for reference.:
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240z - fabbing new front rails
Smithy lathe??? Pshaw! It's a South Bend. Haha!! How's that for lathe elitist? The Monarch guys would all be rolling their eyes... South Bend??? Pshaw! It's a Monarch. LOL! I'd be honored for you to copy all or part of that brake. Let me know if there are any questions. I think the whole thing cost me under $30 US, and I think the only thing I couldn't find at a big box store was the tube for the slides. I'd have to dig out my records, but I believe I ordered a foot or so of DOM tubing for those. The welded stuff at the big box stores wasn't a good enough fit so I think I ordered that.
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Which engine for a 77’ 280z
Haha!!! So you aren't going to warn her?
- Silvermine Motors Electric Power Steering System
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240z - fabbing new front rails
So about my bender... That press brake is only maybe eight inches or so long, but I'm very happy with the way it turned out. I saw the idea on the web and made up the details as I went along. Of course, as with most project, the details are where the magic is. One longer spring I cut into two halves. Two bolts (5/8-11 I think) with the heads cut off for the guide pins. Nyloc nuts (not in pic) to adjust and hold position for different stock thicknesses. I made the bottom die shorter than the top on purpose so it functions like a finger brake with some of the fingers removed. That way I can hang the unbent portion out of the dies and keep a section straight. Here's a pic of most of the parts before final assy: I cut the bolt heads off on the lathe and turned a counterbore shoulder. That way I can press the bolts into the base and the shoulder will make sure they are perpendicular (normal). The shoulder is a little shorter than the base thickness so the bottom is recessed. That way I can tack weld the bolts into place from underneath and the base will still sit flat: I made the dies on my metal shaper. Here's an action shot cutting the first side of the upper die: And here's the two finished. They really should be hardened for longer life, but I'm kinda hoping that with the few bends I make, it'll last long enough without heat treat: So far it's been a great little tool and has enabled me to make such beauties as this: And this:
- 240z - fabbing new front rails
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1976 280Z Restoration Project
I suggested that it was a "feature". You know... Pull in some recirculated air to do a better job removing the humidity? Or something? LOL!! I'm sure there is an applicable Dilbert sequence! If it makes you feel any better, that's not a unique story. The project concludes with praise and honors for the non-participants, right?
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Which engine for a 77’ 280z
I think he knows. His wife hasn't figured it out yet, but HE knows.
- Silvermine Motors Electric Power Steering System
- Silvermine Motors Electric Power Steering System
- 240z - fabbing new front rails
- 240z - fabbing new front rails
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Which engine for a 77’ 280z
My only input into the turbo/NA discussion is that I have no experience at all with turbo stuff. If you go turbo, other than generic "applicable to any engine" stuff, I won't be of any help. Not saying that's a decision factor, but just sayin.
- 1976 280Z Restoration Project