MG Sports Cars

You can always add a filter network, even for an AC signal. Capacitance and inductance in the proper values and the right configuration will allow the desired signal to go through and the filter can be designed with a sharp frequency cutoff that excludes just about everything else. It takes a bit of math and the right sized components, in extreme cases even the creation of what is called a "tank" circuit which is nothing more than a resonant or ringing circuit made up of one inductor and one capacitor. But the goal here is to avoid the noise in the first place so that you don't have to take any sort of extreme measures, which should not be necessary anyway if the wiring is done right to start with.

Jim

OK, then that is the same thing I was thinking.
Jim, how about adaptive speed bump sensors that will raise the car when you approch the speed bumps.

Of course it could be done. But why? If you raise the ride height don't you also raise the spring rate and make the ride over the bump more harsh? Perhaps it would be better to just slow down a bit as the gods intended. Anyway it's probably a bit above my pay grade, doing such complicated stuff. Now if it's more a question of grinding off bits of the car on the bump, maybe the ride's already a bit lower than it should be, or the bits hang down a bit farther than they should. Is it that your bits are just too big? Maybe a large hammer could remedy that.

I do have a picture as promised, everything above and below the trunk is now complete. It's the part in the middle that still needs work

Jim

In the Pantera I have the distributorless ignition. It the pick up on the timing wheel I was getting interferance from the starter motor. I ended up putting a steel plate between the two which seemed to solved the issue. If it is passing near a starter/alternator wire it just might needed a shielded wire.

Got most of the noise out of the CLT sensor by changing the grounds but in the last datalog I noticed some very strange waveforms on the CLT trace. Almost digital in nature, abrupt but very uniform spikes and changes in level. May be nothing to be concerned about, or may be something I have to track down. I suppose I can look for another trace with similar changes.

Anyway, I've about finished the wing reservoir but I'm waiting for some low viscosity (wicking) loctite to treat the welds before mounting and plumbing it. It came out pretty good, with a concealed chamber in the base for the wing attitude pump.

I'm psyching myself up for the wiring checks on the MegaShift controller, which is the last step before the software revisions, and in the meantime I still have intercooler plumbing to do and a pump to mount.

Jim

I am sure you have covered it but your engine grounds need to be good too; otherwise everything is going to find some pretty screwy paths.

Yeah, that's all solid. I saw the signals clean up remarkably when I installed the separate instrument ground post, with a lead directly to the battery ground. But I just noticed these new blips. I'm going to watch that signal for awhile before I assume it actually is noise on the CLT sensor line though. Could have been something like a glitch in the datalog file.

Jim

I've been working on the MegaShift transmission controller installation pretty steadily since my last post and made much progress. But there is more to do. As it stands today, the paddle upshift does not yet work (appears to be a coding issue that Lance will look at), my brake sense input appears to be a signal mismatch which I can fix, the gear readout has a mismatch, possibly an incorrect ground reference or similar, I have to verify the CANbus communication between the MegaSquirt and the MegaShift, and I really should come up with a way to probe the solenoid outputs before firing the beast up. Maybe another month's worth of work.

Also, I need to make a separation tank to take the output of the intercooler condenser and plumb in those lines before I can use heavy throttle for more than a second or two. And there are a few other more minor issues.

I don't really expect to be driving the car to Townsend, shakedown is likely to take me beyond that. But I do expect to make Louisville with it, and to be driving it this summer.

Jim

RE: But I do expect to make Louisville with it, and to be driving it this summer.

Bet you're excited by that Jim. It's been a long time coming; I'm sure you have withdrawals!! You've done so many cool things with this upgrade; it's going to be awesome.

Thanks Rob.
Still got a crooked body, but for now I don't care, I just want to drive it. Anyway the car always was something of a beater and may always be. For the way I drive it though that is appropriate.

Jim

Two steps forward and three steps back.
I'm down to the gear indicator, CANbus, a bit of programming and testing before I can do any driving. Plus hooking up the intercooler before I can drive it hard. But, my digital readout for the gear indicator is broken. As in, demolished during disassembly because it wasn't working right. Including the housing. And since that was made out of the old brake indicator/light/switch there's nothing for it but to find another one. I'm certain I have one here somewhere but it hasn't turned up in the usual places so a whole house search and spring cleaning is on out in the Lab (which actually needs that rather badly anyway) to see if I can locate it. Since that might easily take 2 or 3 weeks and then I'll have to build a new indicator in it, well let's just say Townsend is definitely off the table. Louisville is a maybe but that sort of depends on what turns up in the programming and testing. One possibility that looms hidden in the background is that I could have to learn C++. I hope not, but I have to recognize the possibility. Hey, could be an entirely new career direction, right? Just in time to retire. ;-)

I'll get it done someday. I just don't know when.

Jim

Hey Jim,

I got a ROUNDTUIT if that will help. I can bring it to Townsend and let you borrow. I would just give my ROUNDTUIT to you but what would I do then when the time comes for me to say "I will do it when I get a ROUNDTUIT", I will never get it done.

charles

I got him covered. ;)

Did I ask for a roundtuit? I don't think so. Used to have one I carried in my pocket and it made no difference at all. That ain't it. Nothing I can do will get Lance over the flu any quicker, and all the searching in the world won't turn up that spare brake switch/lamp for the dashboard until it's ready to be found. It's on the to-do list right along with about two dozen other things and a round tuit isn't going to knock even one of those things off the list. I am functioning at maximum efficiency. Today that means taxes. Yesterday it meant plumbing. Tomorrow it will mean something else. Maybe mowing if it is warm. Somewhere along the line the switch will be found, whenever it is ready to be found. I don't think it cares one bit whether I have a Round Tuit or not. :-p

Jim

Agreed,
no roundtuit required in your case Jim.
What you need is my new book, The Procrastinators Guide to Tomorrow.
It should be ready soon.
Helps slow things down a little :-)

Fred

Oh, very funny Fred. Ha, floompin ha. :-p

It's not roundtuits and it's not procrastination. I'm about as busy as a 4 legged ape (see if you can figure that one out). I'm operating at my optimum ratio of work v downtime and without more downtime I just can't get any more work done. Unfortunately sleep counts as downtime. And the MG ranks below certain essentials like keeping the living quarters livable and such. As much as there is on the list ahead of it I'm lucky to get anything done on it at all but I still try to accomplish something every day. Sometimes that stretches into every couple of days, or every few days, but rarely goes a week unless it's a vacation week. But there's also a list on the MG of things that have to be done, first to be able to take it out on the street, then to drive it hard, then to go any distance from home, and lastly for appearances. I may not be able to complete that last list in my lifetime, there are so many things ahead of that, but the car has been a "beater" from the day I bought it so what else is new? I'm pretty comfortable with that usually, other than Show days. But then I never was much of a one for appearances.

Jim

So I'm cooling my heels waiting for a new brake warning light/switch to arrive but not real inclined to do much in this nasty weather anyway. Still haven't found the spare but the new one will have a shiny new bezel which is about the only part I will use anyway so at least that part is good even if the extra cost was not. There simply wasn't any more practical way of dealing with it.

I do have a few other details to see to, putting the air compressor in the trunk and hooking that up for instance, or plumbing the lines for the intercooler and AC condensers. For the IC I'm designing a header tank to work as a fluid/air separator so that only liquid is pumped to the evaporator and vapors are returned to the tank. That is going to be a slick tubular tank about 1-1/2" in diameter and over a foot tall with a bend in the middle and it will mount to the outside of the radiator support rail in the wheelwell. The condenser line will come in about the middle, the suction line to the pump will come out the bottom, and the top will be to the fuel return line. The existing return from the FPR will go to the inlet side of the condenser, since that fuel will have some heat in it from pumping and from being circulated through the fuel rails on top of the engine. That way the EFI system will continuously supply fluid to the IC system, which will provide the return path to the tank and also cool the fuel to ambient.

The IC pump will circulate a much higher volume of fluid in a loop through the evaporator and condenser and when I install the MS-III update will be switched on automatically based on TPS, MAP, and temp inputs. Not much to add there to enable that, the same controller will handle the radiator fans. Since pressure in the system will be essentially atmospheric it will not affect fuel rail pressure. Heat absorbtion will occur right at the phase change temperature of the fluid so the heat transporting capacity of the fluid will be quite high and should cool the blower exhaust pretty effectively. When the MS-III goes in it will have inputs for the thermocouples so I can monitor temps above and below the IC core.

That's about all I have for right now. The wing system is working, though I had to add an o-ring to the shaft of one of the upper cylinders to eliminate a small leak. If I have any more troubles with that I can switch to the new 1300 psi cylinders on top. The bottom may be a bit more interesting. At present I have no cockpit wing attitude adjustment as the peristaltic pump idea didn't pan out but I can sort that out later. Everything else seems to be working, including the bonnet lift and the air suspension which is holding pressure perfectly, though I do need to order a helicoil kit for the fitting on the compressor.

I estimate another 2-3 weeks to get the gear display back in operation and maybe by then I'll have heard something from Lance. If not, I expect I'll be studying C++ and relying on Matthew to review my syntax and look for program errors. He is good at that sort of thing.

Jim

So. Buy an almost thirty dollar switch and when it comes in promptly whack it to bits and discard all but one piece. Who'd do such a thing.

Well me obviously. Nothing left but the plastic housing with even the copper bits and rivets gone. All off in the trash. Well, I did keep the wee bulb but I don't know why I bothered. Not that I can expect to use it for anything. Has a nice shiny chrome plated bezel though, long as it doesn't peel off.

So it's a start for my new gear display. Need to fit the opening with a bit of smoked plastic, find spots for the micro switch, 7 segment numerical LED and 16 pin driver chip, wire it all up and I should be back to business. Only a 2-3 hour job you might expect but no more today I wouldn't think. Maybe some tomorrow.

Tried to post you a picture but technology has defeated me. But have no fear! I am exchanging the iphone for a Windows phone in another day or three and maybe I will be able to resize my photos then. Or I may have to just use my regular camera. But anyway, sorry. No picture.

Jim

Windows phone?! I hope Matthew wouldn't let you do that! If you meant an Android phone, well, Google won't be happy with what you just called their mobile operating system. ;)

[www.theverge.com]

Actually, Matthew has had a windows phone for almost 3 years now and loves it. I think his uses windows 8 but they've recently gone to windows 10. Mine is a @#$%& Lumina 640, I think it uses 7/8. The @#$%& phones are pretty bulletproof so that's a draw. The $30 price was too. Not bad for a device with a 1.8G quad core processor. And I'm a lot more comfortable with windows than I am with Android and iphone, of which I've had both. They are just fine as long as you do regular stuff but just as soon as you want to do anything out of the ordinary it seems you run into walls. At least with windows there is always a workaround.There probably isn't a more sophisticated OS around, and with microsoft now putting their name on the phone I wouldn't expect any hardware/software conflicts either. Phones have now become full featured computers, with the power to run full featured operating systems, so why not take advantage of that?

Have you heard of any problems with windows phones?

Incidentally, I did a bit of trimming of the switch housing yesterday and have the beginning of a plan to install the new innards. I expect to make this version of the DRO much more robust.

Jim