| LIFE OF A GT |
|
|
 | | January 15, 2010 - A long day with not much actual progress.
I managed to cut out a bracket. Oooo!
Actually, I did quite a bit more than that, mostly planning. I was following a pickup this morning and noticed that the shocks were mounted very far inboard. I realized that this would give more wheel travel for a given amount shock travel, and that I had previously considered a slightly more inboard mounting point on the MG. Obviously I wouldn't want to go too far, as my coilover setup would put some pretty major bending loads on the rear end and the lessened shock travel would mean less precise damping. But would it make much of a difference?
So I dragged the rear end back off the workbench were it was set up to have the shock bracket mounted on the driver's side, and stuck it back under the car. A bit of rough measuring showed that my alternate setup would give me an extra 1/4" to 3/8" of droop. Nothing to be ashamed of for such a simple change, and it would also give me more room in the wheel wells. It would also drop the lower mounting point of the shock down considerably, about 1.5" closer to the ground.
However, while doing my measuring, I discovered I'd mis-measured last time and I really had 2" of droop travel from my expected ride height. I suspect I hadn't let the shock fully extend, these AFCO shocks don't have internal pressurization so you have to actually pull them open. If the damping is cranked up, that takes a significant amount of effort. Regardless of the cause, it appears I have nothing to worry about so I'll continue as planned. The rear end came back out and was reinstalled on the workbench.
While poking around back there, I started looking at other packaging concerns - specifically, the available space for a muffler. There isn't much. The layout of the MGB GT's truck is a little weird, though. There's a fairly tall flat floor. If you lift it up, you discover a cavernous hole that exists to house the spare tire and quite possibly enough tools to disassemble the car. If I move the fuel tank into this space, that opens up a huge amount of room for a muffler underneath. I could either move the existing tank without too much trouble or build my own new one with some baffling inside. Mounting the filler is going to be a bit more of a problem as it would then be about level with the tank, but I have an idea.
More work!
entry 253 - tags: packaging, suspension, fuel tank | | |  | February 5, 2010 - I'm still finishing up the garage rework and proof-reading the book manuscript again, so no progress on the car.
Seeing it sitting there on its wheels with an engine inside has me pretty inspired, and I cannot wait to dive back in. So I've been planning.
One of the things I need to do when converting from a 80 hp carbureted engine to a 350 hp fuel injected one is make a few changes to the fuel system. I have a good external Pierburg pump to use, that's good. But the LS1 is set up for a fixed pressure returnless system. Here's the answer - a Corvette fuel filter. It has a regulator built into it, so I just pump fuel in one end and it gives me the return line to go back to the tank as well as the feed for the engine. I'll mount it in the rear of the car by the pump. No adjustments do make, either. Just bolt it in and I'm good to go. I also picked up some 3/8" fuel line to feed the beast, I'll spend some time trying to figure out how to run it up the length of the car.
entry 273 - tags: fuel | | |  | 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 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 | | |  | May 12, 2010 - I'm also looking at laying out the fuel system and the packaging involved.
Not a big problem, really - more on that later. But first, I need a bracket for my fuel pump.
The pump is a Pierburg unit that should have no trouble with the big engine - I hope. It's a round piece with no mounting points. So, with the help of a short piece of exhaust tubing cut in half, I made this little doodad. I'll weld it on to the car and let it cradle the pump.
entry 320 - tags: fuel pump | | |  | May 12, 2010 - The pump is secured to the bracket with a clamp.
That's why the round bars connecting the two "hoops" for the pump. Sharp eyes will notice that the previous photo only had one bar. The reason is that the pump was able to rock too much with the clamp in place. Adding the second took care of that problem.
This is what it's like to build this car. Solving one small problem after another. It's fun. Now, where to put it?
entry 321 - tags: fuel pump | | | May 23, 2010 - I spent part of the day running around looking for a way to connect a new line to the fitting on the MG gas tank.
Naturally, it's some oddball size that was probably created by the Romans and not used anywhere outside MG since 1982. But I think I've got that figured out. The fuel pump is mounted and I'm waiting for a couple of 45 degree fittings to arrive so I have everything I need. It actually won't take long to plumb things together once I have them, I think anchoring the main feed line will take longer than anything else.
I also started mounting the radiator - I'm trying to get most of the metalwork out of the way before I clean up and start running fuel lines and wires. There were a few false starts here as I tried to figure out a good, clean way to mount it. I've got some brackets welded in now that will do the job, but they're not as clever as I'd like and I'm probably going to add a cross bar under the rad to act as some impact protection. The hood closes and there's 6" of clearance under the rad - I consider that a victory!
entry 333 - tags: cooling, radiator, fuel | | |  | May 27, 2010 - The first step in the fuel system - at least, from the point of the fuel.
The flare on the fuel tank is some weird British size, so I attached a new fitting to a short piece of the original fuel pipe. The fit on the compression fitting is so tight that I had to stick the pipe in the bead blaster and clean off the surface crust before it would slip over. The cleaner pipe will help it seal as well.
The two missing adapters I need showed up today in ludicrously large boxes, so I have everything I need to finish the fuel lines. I also started working on the wiring, and I've decided where the ECU will go. It'll be fairly straightforward from here.
entry 337 - tags: fuel, wiring | | |  | June 8, 2010 - A mysterious device I found while connecting the return line.
I think it's a swirl pot of some sort - it was mounted vertically with one of the fittings (marked "IN" here) at the top. The return line from the regulator came into this upper fitting, then the lower one returned to the tank. The little doodad was sitting higher than the tank, so that would work.
Anyone know for sure?
entry 343 - tags: fuel, mystery | | |  | June 8, 2010 - The fuel system is done!
It looks pretty nasty in this picture, partly due to the random wires of various sizes floating around and also due to some weird angles. The angles were chosen so I could use 45 degree fittings instead of 90 degree for less restriction. I also had to squeeze all the components into a fairly small space, of course.
The fuel comes from the tank through the 3/8" feed line, the leftmost one at the top of the picture. It's then adapted up to 1/2", because that's the size of the inlet on the pump. I didn't use 1/2" for that entire stretch because the actual line coming out of the tank is probably 5/16". The fuel then runs to the Corvette fuel filter, which doubles as a regulator. The braided stainless line at the bottom is a -6 AN line (3/8") that runs all the way up to the engine. The return line runs back to the tank through the factory swirl pot mystery cylinder at the moment. The stainless feed line runs through the transmission tunnel and is well anchored to keep it safe and to keep it from sawing through other things.
It took a remarkably long time to get all this done. Not only did I keep having to source adapters, but even securing the stainless line involved crawling under the car, measuring for a hole, drilling from above, crawling underneath to check the location, crawling back out to tack-weld the bolt into the hole, then going back under to bolt it up. Then move on to the next spot and do it again. Add to that the usual "whoops, I left my pen/ruler/wrench/fitting/drill on the table" up and down routine, and it seems as if I spent most of my day simply going under the car and back out again!
entry 344 - tags: fuel | | |  | June 9, 2010 - Mystery solved!
The "swirl tank" is actually a vapor separator as part of the emissions control system. What I thought was a return line was actually a vent for the fuel tank. The vapors collected in the separator traveled up to the engine bay into a charcoal canister and were eaten by the engine. Having the separator in place kept raw fuel from getting fed to the charcoal canister when a full fuel tank would expand from heat.
I can hijak the system to work as my return line - but then there's no venting capability for the tank. Older MGBs had a vented gas cap that let the pressure in the tank stay constant regardless of temperature fluctuations or fuel use. The downside is that they can drool fuel with a full tank on a hot day.
Luckily, the green MG parts car that lives outside is a 1969, and comes with the vented cap (on the right) and appropriate fuel filler tube. Since the charcoal canister from the 1972 car was damaged when I got it, that's my best solution. Looks like I might need to get a new cap though.
entry 345 - tags: fuel | | |  | June 16, 2010 - Wiring time!
This means I'm referencing a handy four-page schematic of the Camaro wiring, the one-page diagram for the MG and referring to the big 100-page book of Miata wiring once in a while. The Camaro wiring is actually going pretty well. The biggest problem is hunting down and fixing a couple of connectors that were damaged either when I pulled the engine or beforehand.
Integrating it into the MG wiring is a bit more challenging, although it did help when I figured out I was trying to reinstall the MG harness the wrong way in the car! I think I need to make a photocopy of the MG diagram and start identifying which sections to keep and which ones will be deleted.
Sharp eyes (and real obsessives) might notice that I've flipped the fuel rail over on the engine. This puts my fuel feed on the passenger's side instead of the driver's. It's just a bit easier to run it that way. Let's hear it for symmetrical intake manifolds!
entry 346 - tags: wiring, fuel | | |  | June 19, 2010 - The rear axle, fuel tank and panhard bar have all been given a coat of POR-15.
So has the pedal box. I also hit some of the brackets welded on the car to use up some of the leftover paint. Once the tank is dry, I can do the final installation and not have to take it out again. Woohoo!
entry 350 - tags: paint, fuel, axle | | |  | August 23, 2010 - Exciting stuff - the fuel filler is in place.
Well, actually, this is exciting. It means the gas tank is bolted into place for the last time. The assembly I'm doing now is final assembly, and that's the exciting part. Real progress: the pile of parts around the car is shrinking!
Originally, the fuel filler on the tank entered the trunk floor straight below the filler neck. You can see the patched and repainted hole in this picture - it'll be covered by sound deadening or carpet when the car is assembled. Since I had to move the tank over to make room for the exhaust, I had to make the filler wiggle over a few inches. A bit of back-room shopping at NAPA yielded a filler hose with a 45 degree angle. It worked out perfectly.
entry 367 - tags: fuel | | |
|
THE DIARY