Captain Obvious

That's cool. If I had more time and more money, I'd do all sorts of expensive time consuming stuff, and one of them would be to drive the whole Route 66 from one end to the other.

I'll let you know in a week or so. A local Z buddy of mine recently ordered a bunch of those thinking they might look good. They'll be here shortly and when they get here, we'll try them out to see what they look like. As for a name? No idea. That technology is moving so fast and furious right now that I don't think there are standards to describe them. Other than the BA9S base, I don't think there's anything to describe them other than "oversize" or not.

Yup. That's exactly what would happen. The incandescents will always dim just fine, but the fewer of them you have remaining in the system, the less you'll get the LEDs to dim. And by the way.... As far as the dimming function goes, the stuff like the brake indicator, turn signal indicators, high beam indicators... None of those are connected to the dimmer so they don't matter one way or the other. Leaving them as incandescents won't help your LEDs dim. Only the incandescents that are dimmed will matter. On the 78, the only things that are dimmed (besides the gauges themselves) are the hazard switch, the HVAC faceplate, the original radio bezel, and the A/T shifter bezel (if you've got an automatic). So if you've got a manual trans 78 with an aftermarket radio and have already updated the HVAC bezel, then you've only got one tiny dimmed incandescent lamp remaining in your system and that's the one in your hazard switch.

I don't get over to Hybrid much, but I did see the thread a while ago. I gotta say that I'm more than a little impressed. That's some nice work on such a huge undertaking.

Haha! Glad to help. So my previous owner removed my cargo straps completely and I've been looking for options. I did pick up a pair of old straps off a junker a while ago, but they are very faded. Supposed to be black, but they're a pale blue/gray. I like the ratcheting ability of your mod too. Nice work.

Wow. Very nice. So you're "Captain Overkill"? So you've got access to all sorts of machinery to cut that prototype head, and the only thing you can find to finish off your brackets was freehand on a belt sander?

Cool. So far. so good. I suspect that as you increase the number of LEDs in the system (and reduce the number of incandescents) your "range of dimming" will decrease. You'll always still be able to get full bright, but the "dimmest" lower end will move up. And with that in mind, I think I would concentrate on LEDs that are dimmer rather than brighter. Everyone selling LEDs seems to advertise how BRIGHT they are and all the customers seem to think that the brighter, the better. I've done a little bench testing with a few LED bulbs in spare gauges and I've come to the conclusion that you don't need much. Now, I also know that how much brightness you want from the dash is different for everyone, but I'm not looking for way brighter than stock. I want white, not necessarily a whole lot brighter. YMMV.

The problem is the huge disparity of currents between LED's and incandescents. If you make the pot large enough that the LED's will get completely dim, then your incandescents will all go completely dark in the first ten percent of rotation travel of the pot. And if you make the pot small enough that you get reasonably good control over your incandescents, your LED's won't ever get completely dark. I think the best solution is to use all one technology or the other and not try to mix the two. And if you DO have to mix the two, a PWM dimmer would do a much better job of handling the two differing technologies because it's a duty cycle based control instead of a resistance based current limit. I think that if you do switch everything over to LED's, a 400 Ohm pot would be a good place to start. You could use traditional fixed value resistors first though just to test the brightness and then once you're confident on the upper end, buy the pot. But be warned... I expect you're going to run into the same problem with the pot shaft being too short and will need some sort of extend like what I did for the PWM module I made.

It's the one that points toward the radiator. Vacuum from that front port should "T" to go to two places. 1) the distributor vacuum, and 2) the carbon canister control line. I think I've got a spare throttle body in the shop. I'll snap a pic or two and label the connections when I get a chance.

And while we're on the subject... I'm no bulb expert, but I did do a little digging recently as a result of some of the stuff I'm doing to my car and here's a little bit of "Bulb Theory 101" that I picked up along the way: The "BA9S" simply describes the BASE size and shape. It does nothing to describe the glass shape. For example: "BA9S" - Means "Bayonet base which is 9mm in diameter and has a single filament." Bulbs with a BA9S base can come in one of many different envelope shapes: G = "Globe" - These are spherical (like a globe) T = "Tubular" - These are usually longer than they are wide. S = "Straight" - These are supposed to have straight sides, although they often do not...? In catalogs, the envelope shape letter is followed by a number, and that number is diameter if the glass envelope measured in eighths of an inch. Yeah, I know... I didn't make up the nomenclature. So, for example, you'll see bulbs listed as "G3-1/2" or "T3-1/4". What that means is: "G3-1/2" - Means "Globe (spherical) bulb with a globe diameter of 3.5 eighths in diameter or about .4375 in diameter" "T3-1/4" - Means "Tubular shaped bulb with a globe diameter of 3.25 eighths in diameter or about .406 diameter" I did a bunch of digging into the original bulbs (Toshiba A12V3.4) and I've come to the conclusion that they are not available on the free market. They are a BA9S base, but the glass portion measures about .310 (8mm) diameter. Using the modern nomenclature, this would be a "G2-1/2" and I've not found that size anywhere. Might be completely ubiquitous on the other side of the planet, but not here. I've not checked if the larger G3-1/2 bulbs will fit through the hole in the back of the gauges, but I have confirmed that the small T3-1/4 bulbs fit fine. In other words: "A bulb with a BA9S base and a T3-1/4 envelope fits in the dash gauges." Sorry you started the discussion?

I've found the easiest way to change those little bulbs is to: 1) Put on a rubber glove on hand because the rubber provides better friction to the glass globe. 2) Pull back on the center wire a little to compress the spring inside the socket. 3) Once you're not fighting the spring anymore, turn the bulb with your gloved fingers. Once you get the hang of it, it's really pretty easy. Don't try to push the bulb in to compress the spring and try to turn it at the same time. It's much easier to compress the spring with the other hand. Works great for insertion as well as removal.

And one other thought about leaving an incandescent in the system. I suspect the people who have replaced their dash gauge bulbs with LED lighting have done just that... Either by accident, or on purpose, I suspect they have left a bulb or two (or more) as incandescents. Depending on year and options, some possible culprits include: HAZARD switch, cigarette lighter, HVAC faceplate, A/T shifter bezel, original radio. If you got a 260 with an auto trans, you could leave FIVE incandescents in the system and still have LED's in all your gauges.

I was asking about mods like a headlight relay upgrade because if you would have done that mod, you would probably have an unused wire going through the grommet on the passenger side that could have been re-purposed for your fan override. Independent of your fan controls though. Yes, I would recommend a headlight relay upgrade. The original switching system is overtaxed by the headlight current and I'm continually surprised they didn't use relays in the original design. They used a relay for the fricken horns, but they didn't use any for the headlights??? You've got a 78 right? Already has an internally regulated alternator.... Just musing ideas.

Kurbycar, Yes, LED's can be dimmed just fine using a regular potentiometer, but there's a catch... The catch is that the potentiometer must be of an appropriate value sized for the current going through it, and the stock dimmer pot is not of appropriate value for LED's. Goes like this... The stock dimmer pot is adjustable from 0 to 10 Ohms. When it's cranked to 0 ohms, you get full brightness. No problem. Problem comes into play when you crank to full dim... You're putting a 10 Ohm resistor in series with the LED (or LED's if it's a bulk string) and they could care less. The LED's draw so little current that there's very little voltage dropped across the 10 Ohm pot and the LED's still light up at near full brightness. If you include one incandescent bulb somewhere (or a low value resistor instead) wired in parallel with the LED's, that one incandescent bulb will provide a low impedance path around the LED's and allow significantly more current to pass through the 10 Ohm pot. The additional current through the pot will increase the voltage drop across it and the LED's will have less voltage to work with. You probably still won't get full brightness range, but at least you'll get more range than you would without the bulb. If you really want full brightness range, you need to switch to a higher pot value (probably on the order of a couple hundred Ohms) or switch to a PWM type dimmer. http://www.classiczcars.com/topic/52446-pulse-width-modulated-pwm-dimmer-control-upgrade/

I think there are only two electrical grommets that go through the bulkhead wall. The big one on the driver's side (for the EFI) and the big one on the passenger side (for everything else). I'll take a look at the wiring diagram and see if I can come up with any bright ideas on a wire you could repurpose. This is for a wire that goes hot when you hit your override switch, right? Connects to green on your control relay? You done any other mods like a headlight relay upgrade?

T-handle looks great, but somehow the thought of grabbing ahold of two pounds of sub-zero stainless steel on a frigid Canadian winter morning just doesn't do it for me. Sounds too much like a tongue on the flagpole. To each his own though. I certainly owe you! I can cut them a tiny bit tight and you can lap to perfect fit? Shoot me a PM.

Cool. Sounds like you found good stuff in the glove box! So another crisis averted, Bring it up again if you need additional input.

A couple thoughts... First, If the Z transmission is like others I've been into, you're less likely to hear any gear whine in fourth gear because it's a straight shot through the gearbox without going through any of the counter-gearing. Because of that, none of of the internal gears are actually under any load. They're just along for a no-load spin in the oil. All of the power goes in the input end, straight through a locked up main shaft, and then out the output end. Second, I've noticed that a LOT of transmission noise is transmitted through the shift knob design. I've messed with a couple different knob designs and I've found the quietest versions are solid, heavy, and have all parts either completely firmly mounted, or shock mounted in some sort of elastomeric adhesive (fancy words for "RTV"). Third, I made shifter bushings out of Delrin. Doesn't add anything to the discussion, but just because I can. They turned out awesome:

Haha! I just hope the next owner of my car doesn't consider me "The Typical PO". I suspect it's inevitable, but I can dream, right? Heck... I'd buy a car off of me.

I believe that all LED's are inherently very dimmable. Assuming you don't overheat it, the more current you push through the die, the brighter it gets. Works great from almost no light emission, all the way up to max brightness where you can't dissipate the heat anymore. But in the world of using LED's for "real world applications" like home lighting and automotive lighting, it's not that simple. The problem is that the LED's you purchase for pre-canned applications (like 120VAC home lighting applications or 12V automotive lighting) are more than just a simple LED. They are multi-component assemblies and unless you know what comprises that "assembly" you cannot guarantee how well they will react to a dimming attempt. Some of the assemblies are simply a couple LED's in series with a current limiting resistor. These should gracefully handle an attempt to dim them. But on the other hand, some of the assemblies are much more complicated than that and attempt to account for wider supply voltages and these might not react favorably to an attempt to dim them. Then there's the WAY they're dimmed... The original resistor potentiometer based dimming scheme won't work if you convert ALL your dimmable bulbs to LED. You'll need to keep at least one incandescent bulb in the system somewhere, or switch over to a PWM based dimmer system.

Awesome. I don't know much about racing... Were you in a stock class with (hopefully) similarly performing cars? And as for your wire back into the interior from the engine bay, I don't have any silver bullet for that. Unless there's some function that you have stopped using such that you could repurpose an old wire for a new application, I don't have any great suggestions. Push a wire through the existing grommet?

Yeah, I try to do the same, but I'm not completely diligent. Sometimes when I complete fix or project, I just want to stop thinking about it and don't catch up with the paperwork like I should. So I'm with ya. I pity the next owner of my car. The worst ones for me is opening something up to mess with it and see some marking or writing inside there in MY handwriting clearly indicating that I've been in there before, but don't remember when or why...

Glad you got the glove box open. Now that you can see both sides of the lock, is it clear why the key turns, but doesn't open the door? And Cliff, I'm getting mixed messages from your poster as well... Is the decline in place only WHILE drinking? Because, as you witnessed, I can certainly attest to the validity of that!

One Way, This site is a very valuable resource for me as well and I try to give back when I get the chance. I'm no Z car expert or anything, but I try to help where I can. Stay warm and dry, and here's to hoping you guys get back to normal as soon as possible!