| THE MG |
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 | |  | February 9, 2010 - I wanted to do an ergonomics check, so I installed the driver's seat to see how everything was working out.
The gas pedal was held in place by a vice grip, the brake pedal return spring kept that in the appropriate place and the steering column was clamped on. The initial fit showed that the steering wheel sits very low. That's odd, given that my various collection of test wheels are all significantly smaller than the original. When I checked the MG column against the Miata one, I realized the difference was due to the bracketry on the column. With that taken into account (as seen here), the wheel was just about perfect. It needs to come a bit closer to the driver to be ideal, but that's easy.
The shifter is perfectly placed and everything feels good. I think it'll be a good driver. Don't mind the steering wheel, that's just one of the testing units. Although it's not exactly offensive.
entry 279 - tags: ergonomics, steering | | |  | February 9, 2010 - Check out my new muffler!
Some people use fibreglass or stainless steel wool for muffling, I use yogurt. This box is the same dimensions as a Dynomax Super Turbo, other than the lack of rounded edges. I crawled under the rear of the car and whaddya know, there's enough room for duals! Only barely and I have to move the gas tank over by 3", but I can do it! This is excellent, it means more power and more quiet, both good things. I'll have to figure out how to package an X pipe (and why) so there's some good learning ahead. I think I'll order a single muffler now so I can ensure the fit is good, then go ahead and move the tank.
I've also been researching fuel line parts. What a pain. I'd been hoping to avoid AN fittings but I don't think that will be possible. Our local Parker distributor has gone out of business so that makes my previous plan of using SAE flares more difficult.
entry 280 - tags: muffler, packaging, fuel | | | February 10, 2010 - I think I've sorted out how the fuel system will work.
I've ordered the always-necessary random bits and pieces. Turns out using AN fittings won't be such a problem, and this way I'll have a sexy braided fuel hose! It should come together fairly quickly when I start work. I've also ordered a muffler to confirm fitment.
I'm procrastinating. I really should be working on the metalwork around the transmission. But Janel's under the weather and asleep on the couch, so it would probably be rude to fire up the grinder, drill and Sawzall. Soon.
What I'm really trying to decide is if I should just bite the bullet and pick up a Painless wiring harness. I've wired cars from scratch before, and it's not that much fun. I've modified stock wiring harnesses, and that's possibly even less fun. It's so tempting to simply have something I can plug in with no mystery or work on my part. If it'll cut a month off the build time - that seems like a lot, but it's actually plausible especially when you consider my lack of experience with these engines - then it's probably worth it. I'm getting so lazy.
entry 281 - tags: wiring, fuel | | |  | February 13, 2010 - It's time to start putting some new sheetmetal in the transmission tunnel.
I don't particularly enjoy this part. The driver's footwell was giving me some hassles because it had an odd shape in it - a section pushed outwards. I'm pretty sure this was because the same chassis was used in RHD and LHD configurations, as it gave great footroom if the driver had been a passenger. As it was, it was useless space behind the pedals. Based on my anticipated exhaust routing, I think it'll also be a problem then. So I chopped it off.
By now, the hole has been filled with a flat plate. This makes it much easier to match my new sheetmetal to the straight edge instead of the factory bends, and I'll never miss the space behind the pedals.
entry 282 - tags: packaging, sheetmetal | | |  | February 14, 2010 - I wanted to see how the Miata steering column would sit with the dash.
My concern was that the location of the column would leave bare metal exposed. Well, that's not a problem. With the length of the unmodified Miata column, the standard column shroud is an almost perfect fit! I'll have to trim the bottom a bit to clear the shape of the dash, but that's easy. I'd also been worried the Miata parts wouldn't match the MG interior, but I think it's going to blend in really well.
In the picture, it looks as if it's hiding one of the gauges a bit. It doesn't look that way in person, but this is a 1999-05 shroud. I can also use from from a 1990-97 model, which is a little bit more square and might give a little more clearance.
The steering wheel will need to be a bit of a deep dish style to match the MG distances. But that's easy to do later as I fine-tune the ergonomics.
entry 283 - tags: ergonomics, steering column | | |  | February 14, 2010 - Mounting the steering column was easy enough.
I drilled out the spot welds holding the bracket to the MG column, and simply transferred it to the Miata part. It's just tack-welded here for a final test fit.
And with this, the steering column is finished. The car will sit on its wheels and can be steered. Progress is being made.
entry 284 - tags: steering column | | |  | February 16, 2010 - The folks on the LS1tech.com forum are very enthusiastic about modifying stock harnesses.
So before I dropped a big pile of cash on a Painless setup, I figured I'd give it a shot. I started by making a spreadsheet of all the wires in the ECU connectors, what they did and if they should be kept.
It turns out that even the oddball 1998 Camaro harness is very well documented. With the help of LS2.com this only took a moment. I walked through the list and put an X beside every wire I wanted. No VATS (anti-theft system), no EGR, no second O2 sensors, no fuel tank pressurization and no charcoal canister. Also, I didn't feel it necessary for the low oil signal to pass through the ECU.
All of this work was done with the Jaguar looking on, representing Lucas.
entry 285 - tags: wiring | | |  | February 16, 2010 - Nice work, GM!
The connectors for the ECU (actually, I think the term is PCM but I'm going to stick with my usual) might be huge, but after you pop off a couple of plastic covers I discovered that they're ridiculously easy to modify. Simply lift the wire terminal of choice upward a bit and lift the tap on top a bit further, then push. The wire slides right out. I used a dental pick when I was dealing with a single terminal in the middle of a bunch of others, but it's possible to do this with your bare hands.
A couple of minutes later, I had removed the wires I didn't want. If I decide to put them back later, they just push in.
entry 286 - tags: wiring | | |  | February 16, 2010 - After all the extra wires were popped out of the connector, I started pulling them out of the harness.
I'd follow them back through the other wires to find what connector they went to. I unwrapped the harness (put together with a minimum of super-sticky tape, unlike the Miata!) and used zipties to hold it in shape.
Some connectors had other wires that were shared, typically power and ground. These were chased back to junctions with other wires and snipped off. The pink power wires will have to be taped up before I energize the harness. Gradually, the harness got simpler and simpler.
I used LT1.com (no, that's not a typo) to identify some of the wires in the various inline connectors. The "keep" wires that passed through these were typically things such as gauge information, so I pulled them out of the inline connectors, coiled them up and labelled them. I also replaced a hacked-up tach wire with one of an identical color - did the Camaro previously have a big aftermarket tach?
The Jaguar approves.
entry 287 - tags: wiring | | |  | February 16, 2010 - With the harness simplified, I laid it out over the engine.
Next I had to find a place to stash the enormous ECU. It's huge! Newer ones are smaller - but I don't have a newer one. With the removal of the AC system inside the car, there's some room above the passenger's feet. It would be hard to disguise the big modern heatsinked box though.
The MGB, like many other Little British Cars, is ambidextrous and uses the same chassis for RHD and LHD applications. There are even plates covering over the holes where the pedals would pass through the firewall. This leaves a fairly large space where the RHD pedals aren't, and it's the perfect size for the ECU. As a bonus, the Camaro keeps its ECU in almost exactly the same place so the wiring lengths are almost perfect. I can even reuse the Camaro bracket.
It seems I get lucky with packaging once in a while on this project.
entry 288 - tags: wiring, packaging | | |  | February 16, 2010 - My plan has been to somehow stuff an electric speedometer inside the classic Smiths case.
The Camaro's T56 uses an electronic sender and the MG has a completely mechanical version.
Of course, I'm a long way from needing a speedo. But I'm not feeling completely healthy and poking around wires is more attractive right now than cutting and welding. Thus the electric emphasis of the last few days.
Well, it's not going to be easy. Looks like quite a challenge, actually. Enough of one that I started looking for alternatives. I already know of one, which is basically a small electronic motor in a box that takes an electronic signal in and spins a cable at the appropriate speed. It's a decent option, although a bit more of a kluge than I'd prefer. If you're converting a Miata with molded plastic gauges, you don't have a lot of other options. But the MG uses individual gauges, of course.
Poking around, I discovered that there actually exists an electronic Smiths speedo. It's not a perfect match to what I have, but it's awfully close. Close enough to work. And as a bonus, it's actually significantly less expensive than the little "gerbil box" motorized adapter. Excellent.
What about the tach? It's expecting a four-cylinder, so it'll read twice as fast with 4 pulses per crank revolution instead of 2. Some poking around pulled up an article on the British V8 site that explains how to add a potentiometer to easily make the tach adjustable. But wait, it gets better. 1972 was the only year to be fitted with a potentiometer from the factory. At the time the article was written, it wasn't known if this gave enough range to make it work with a V8, but I'm very willing to find out. If not, I'll just solder in a different one. Perfect.
entry 289 - tags: gauges, wiring | | |  | February 20, 2010 - I've been trying to figure out what order to do things in right now, and I've decided to work on the exhaust.
I'm not really sure why that ended up at the top of the list, but there you go. It could be because the Super Turbo muffler I ordered showed up, and so now I know for sure there's enough room for it to fit.
The tip is one from a Flyin' Miata exhaust that I brought home to try for size and to see what Janel thought. She likes the style - they're really nice looking, with a double-walled tip with a constant outer diameter and a rolled inner shell - but thinks it's a bit big at 3.5". No worries, we have 3" ones as well which I think will be perfect. I like the slightly slanted tip.
Is it too early to pick out exhaust tips? Of course not!
entry 290 - tags: exhaust, tip | | |  | February 20, 2010 - Of course, building the exhaust means building the headers.
I've been digging around trying to find recommendations on primary tube length, but to no avail. A diameter of around 1.625" or 1.75" seems to be the one to use, and since the last header I built used the latter I will probably do so again as I have some spare parts - including this collector.
The header flange is GM part 12480130, and it's 7/16" thick. Beefy! The blue pool hose? Well, that's how I do my initial layout testing. I'll figure out the general routing of the tubes first then fine-tune them with a very cool tool that will be making an appearance soon.
But there's no need for it. When I installed the steering column and started to figure out where the collector was going to go, it became obvious that there was no way to run a long-tube header in the car. I simply don't have the room - and that's with the collector in the wheel well! So it appears I'll have to settle for good flow instead of a nice extraction design. Oh well, it'll be an improvement over the stock units at least. And it should be easier to make this way.
entry 291 - tags: header, headers, exhaust | | |  | February 20, 2010 - I saved these two Miata downpipes from the dumpster a few years back.
Flyin' Miata was moving and a lot of random, outdated parts were being sent to the scrapyard. Well, they're not much good as is. But they do have new stainless steel flex joints in them! So I'll cut those out and use them in the exhaust system. I don't expect the engine to move much, but it can't hurt.
Recycling at its finest.
entry 292 - tags: exhaust | | |  | February 20, 2010 - Before I can start fooling around with the exhaust, I need to confirm that the twin mufflers really will fit.
I'm almost positive they will, but it's time to move the gas tank. This is far less difficult than it sounds. The tank bolts to the bottom of the flat trunk floor. I simply had to drill a number of new holes 3" to the left of the existing ones. The large hole for the filler required a hole saw, but otherwise it was quick and easy work.
entry 293 - tags: fuel tank, packaging, exhaust | | |  | February 20, 2010 - I did have to make one small alteration to the fuel tank.
This corner bumped up against my Panhard bar mount and kept me from getting the tank quite snuggled into position. A moment with the grinder solved that problem. You can see that the stock tank is actually crimped together. I was careful to stay clear of that section.
While I was goofing around underneath the car, I also removed the rear axle and relocated the lower shock mounting points an inch higher. This will give me a better bump/droop ratio for the suspension travel.
entry 294 - tags: axle, fuel tank | | |  | February 21, 2010 - In order to fit the muffler under the car, I needed to take a chunk out of the wheel well.
You can see it at the lower right of the photo, it hasn't been cleaned up yet. Since the track is now wider than it used to be, this doesn't cause any sort of interference problem with the tires.
I also chopped a seam off the rear frame rail, visible at the top right of the photo. This rail was originally where the rear spring attached, so it saw some decent loads. But with the new coil spring setup, only the bumper is attached back here. By taking off the seam, I'll be able to move the muffler up by about 3/8". Hey, packaging is tight!
entry 295 - tags: exhaust, packaging | | |  | February 21, 2010 - I've spent the weekend looking at exhaust options, figuring out how it will be routed and what components will make up the final design.
The two collectors in the picture are a couple from my collection. The grey merge collector on the right is an Edelbrock piece, one that I've used before in another build. I only have one of these.
The one on the left is of unknown parentage and will take more work to use as I'll have to cut and weld a star in between the tubes, while the Edelbrock is a slip-on. I have a pair of the basic ones.
The Edelbrock, being a merge collector, will theoretically flow better. But it has a 3" outlet (most collectors don't go much smaller) and I'll have to neck it down to 2.5" almost immediately - I'll use a Flowmaster ball joint connection to do that. So the benefit of the merge collector may be lost. The simpler one is also a 3" outlet, but it'll be shorter in length when assembled. The fact that I already have a pair of the simpler ones makes me think that's what I'll end up using.
I've been trying to figure out how to route the exhaust pipes over the axle. That leaves me short of space for an X-pipe, adds a bunch of bends and gets very tight just behind the axle. The idea is that running under the axle will be bad for ground clearance. But then I realized that the axle at full droop won't drop below the level of the floor pan. This means that if I run the exhaust pipes straight back, they'll clear the axle and ground clearance won't be affected at all! As an added bonus, it'll give me more room to run an X. Excellent. I just put in a big order for exhaust bits that will let me finish pretty much everything but the headers.
I thought I remembered the same thing being done on the Dan Masters build. I checked the photos and yup, it should work.
I have pretty good ground clearance on this car. The lowest point will have right around 4.5" clearance from the ground.
My decision to do exhaust now actually makes sense. It's not as flexible in packaging as some of the other components. Once the exhaust is sorted out, I'll be able to determine the location of the fuel pump and filter as well as the lines to the front of the car, keeping the fuel away from the hot pipes wherever possible. The same goes for wiring. I'm also looking at the cooling setup, but more details will come on that.
This is a really fun part of the build.
entry 296 - tags: exhaust, packaging | | |  | February 26, 2010 - Parts are starting to arrive from all over!
Del City provided this 10-circuit fuse block. I figure I only need 6, but more can't hurt. The MG only has about 4 and they're all devoted to lighting from what I can tell. If I only need 6 of these 10, I'll integrate the two boxes.
I also picked up a big master circuit breaker. It'll give a bit of "uhoh" protection. It also lets me cut the power to the whole car, which is really handy when it comes time to work on things or to store a car for a while.
Most of the post-header exhaust parts are here as well, and the big box from AFCO will arrive Monday. I'll have no excuses for not working on the car shortly!
entry 297 - tags: wiring, exhaust | | |  | March 1, 2010 - More parts have arrived!
This shipment is from AFCO. Along with some interesting suspension bits for the Targa Miata came this radiator. It's a dual-pass setup for maximum efficiency and it's huge! Seriously, it's the smallest rad I found that I thought would work and it's also the biggest radiator I thought I could fit: 26" wide and 20" tall. There's going to be some serious surgery ahead to make this work, and I think it's going to also entail hood pins. I just hope I can make it fit without hanging it down below the body.
There was one more option, a Scirocco style unit. Nice and small, also a dual pass. But the core size is 12.5 x 18", and my current rad is 18.5 x 22.5". That Scirocco one is just tiny. There are also some single-pass units that are a bit smaller, but the dual pass packages better in terms of outlet location.
Eek, this is going to be a challenge. At least I know that, once installed, this car will be immune to overheating. I hope.
entry 298 - tags: cooling, packagin | | |
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