.comment-link {margin-left:.6em;}

Thursday, February 23, 2006

 

FrankenSentra

Here's a very impressive creation put together by another automotive mad scientist.

The ActiveTuning Blog: VQ35DE In B13/B14/B15 Sentra

This guy has found a way to yank the V6 out of a Maxima and drop it into a compact Sentra. While this swap was done with a current model Sentra, he's looking to drop it into an earlier model to make a pocket rocket with about 1 hp per 10 lbs - at the front wheels. I'm amazed that it fits.

Friday, February 17, 2006

 

How not to put a fire extinguisher in your car

I ordered a fire extinguisher Wednesday from McMaster-Carr, and it arrived today. I haven't installed it in the Dart yet, but I thought I'd take the time to list some general things to avoid when putting a fire extinguisher in your car. Sometimes I'm quite surprised at how many fire extinguishers there are sold for automotive use that are not actually approprate for use in a car. Here are some do's and don'ts for automotive fire extinguishers.

1. Do get a fire extinguisher that can put out anything in your car that will burn. The BC-rated fire extinguishers, like the one sold by APC, are rated for putting out oil, gasoline, and electrical fires. But what if your upholstery catches fire? They aren't designed to put out burning cardboard, stuffing, or cloth, just liquids and electronics. Conventional fires like that require an A rating, so an ABC-rated fire extinguisher will work for a typical car. If you have something like a classic VW Bug, you may even want to consider getting a D-rated extinguisher (in the garage - as one anonymous contributor pointed out, there aren't any small models suitable for carrying around in the car) designed for putting out magnesium fires. Class D's aren't designed to put out normal fires, but if you have to deal with an engine fire when your crankcase is made of magnesium, this can be your only option.

2. Do mount your fire extinguisher securely with a metal bracket designed for vehicle use if you're going to . For the longest time I was guilty of keeping the fire extinguisher in the Dart secured with a cheap plastic bracket, and before then, I had it under the seat. In either case, it can come loose in a crash.

3. Don't attach the fire extinguisher to anything plastic. Plastic trim is barely strong enough to hold up the weight of a fire extinguisher on its own, let alone keep it from breaking loose in an impact.

4. Don't put the fire extinguisher where it will block your vision. It used to be trendy to carry a fire extinguisher on the windshield pillar. It's much safer to have a good view of the road than a great view of your fire extinguisher.

Good places to put a fire extinguisher often include on the transmission tunnel, under the dash, or in the trunk. In any of these cases, be sure you can attach the fire extinguisher to the metal structure of the car and not a plastic or cardboard pannel. Just where you can fit an extinguisher and find a good piece of metal will vary from car to car.

 

Throttle linkage, part 2


So I managed to get the Lokar throttle cable attached to the Crown Vic throttle body tonight. It turned out to be simpler than I thought, even though the throttle cable is meant for a Holley carb and not fuel injection. I had expected to need to make some sort of connecting link to attach the cable end to the throttle lever arm. But it turned out that I was able to use much of the device on the end of the cable. Its original end had a bolt that fit into a ball and socket joint on the end of the cable. I popped the bolt out of the socket and popped the socket over the stud where the original Ford throttle cable attached.

I also needed a bracket to hold the end of the cable. I made mine out of three sections of aluminum angle extrusion. The only tools required were a drill and hacksaw, and it mounts to the bolt holes that also attach the throttle body to the intake manifold adapter.

If there's one thing about this setup that worries me, it's that the throttle moves a lot in the first small movement of the cable. Then again, a lot of engines have throttles that move this way - often to fool casual test drivers into thinking the engine's more powerful than it really is, by making the engine give a big surge of power when you just tap the pedal. I don't think this will give it too much in the way of drivability problems, and if it does I can always make a different bracket that puts the cable attachment point up a little higher.

Now I just have to attach the other end to the gas pedal. This throttle cable is turning out to be easier than I expected - and when you're trying to build a fuel injected slant six, not many things are easier than expected.

Monday, February 13, 2006

 

Wings on front wheel drive cars

It's time for another episode of Mechanical Mythology. This time, I'll tackle a batch of automotive wing misconceptions.

Claim: A front wheel drive car cannot benefit from using a rear-mounted wing to create downforce.

Status: False.

Many people assume the purpose of a wing is to give the driving wheels more traction under acceleration. If this were the case, a rear-mounted wing would have no purpose whatsoever on a front wheel drive car. After all, it's not going to smoke the rear tires when you floor it.

The truth is that many winged race cars cannot generate enough power to smoke the tires at speeds where their wings are effective. In reality, the wings are there to help generate force for cornering, not acceleration. Most compact cars on the market today can benefit from considerably more grip before they are in any danger of overturning.

Some have argued that front wheel drive cars still do not need rear downforce because they are prone to understeer. However, as many experienced racers will tell you, this certainly is not true of all front wheel drive cars under all circumstances. I used to autocross a Ford Probe GT where the rear tires would lose traction if I stepped on the brakes - or sometimes just lifted my foot off the throttle - while turning hard. And a bit of rear downforce can help make sure your car keeps all four tires on the ground, as many front wheel drive cars are known for cornering on three wheels.

Also, note that production race cars that use wings also use air dams and splitters to create downforce on the front wheels. These are often less obvious mods than the rear wing, and such mods frequently appear on both front wheel drive and rear wheel drive cars.

A wing would appear to be more out of place on a drag car, except for high powered rear wheel drive cars like Pro Mods that actually need downforce to get traction. However, some drag racers run wings to stabilize the car under braking at the end of the strip, trading a little speed for a larger margin of safety.

All this assumes that the wing actually generates downforce and the car's tuner has correctly taken this into account when setting up the suspension. Neither of these may be true for the average winged car you encounter on the street.

Sunday, February 12, 2006

 

Dubious product of the month

And the award for "Most irrational operating principle for a questionable gas mileage enhancing gadget" goes to...

The Bio-Pro QX-3 Econo Fuel Chip by Fuel Chief!

It's hard to start about what is wrong with this explanation - I haven't seen such a bizarre butchery of physics since I found Dr. Gene Ray's Time Cube. They are claiming that it provides energy by sending photons into the gas tank. Now, photons are the carriers of light waves, so whether it emits photons should be easily tested. Two obvious questions:

1. Does the Fuel Chip emit light if you put it in a darkened room?
2. Does the light shine through a gas tank?

Even if its operating principle didn't break so many laws of physics, the product they sell doesn't even seem to match its own operating principle! If you wanted a device to supply your fuel with photons, I'd think a light bulb and a clear stretch of fuel line would be the way to test out this theory. Not putting stickers on an opaque gas tank!

But I think this may be my favorite line about these products:

"While the QX-3’s adhesive is strong, we recommend using super glue to securely attach the QX-3 to the gas-tank."

So they didn't even bother to make them with the right glue to stay in place for their intended use.

I've seen dozens of websites pedaling dubious automotive products, but this takes the cake.

 

Mad Pseudoscientist Update

Remember the story about the guy who tried to make a book about cancer entirely by cutting and pasting comments from websites? Dawno, the sparkly eared moderator of Absolute Write's blogging forum, took it upon herself to actually order a copy of the book and see if she could locate the original text to the book. Now her analysis is up at the following link:

NVNC ID VIDES, NVNC NE VIDES: Survival of the Stubbornest

Sure enough, there's only a few teeny snippets of original text. Some entire chapters were made with one hit of Ctrl-V. Sources vary from widely respected scientific authorities to outright quacks. Things may get interesting now that Dawno has allerted the book's real authors that their words have been sold without their permission.

This doesn't reflect very well on either Pavel the Cancer Boy for his content stealing, or PublishAmerica for the fact that they printed this book. Real publishers have fact checkers to look through how-to books and at least be sure the author has properly cited his sources and not misinterpreted them. Of course, real publishers also know that editing does not consist of running MS Word's spell and gramar checks, and that marketing does not consist of the author begging individual bookstores to stock his book...

Labels:


Saturday, February 11, 2006

 

Turbo slant six throttle linkage, Part 1

Today I decided to tackle the Dart's throttle linkage. First thing I did was figure out where to attach it. The most convenient spot seemed to be the bolts that hold the throttle body to the adapter, so I went about making a bracket from aluminum angle extrusions. They're available at most hardware stores and easy to cut with a hacksaw.

Then I found that my throttle cable - menat for a slant six Diplomat - was a bit short. Plus, its end design was not a good match for the Crown Vic throttle body. So I hit the parts stores to see if I could turn up anything of interest. After looking at a few pieces that would need to be special ordered, I finally decided that if I were going to special order a throttle cable, I'd make it a Lokar piece. They're a bit expensive and a little flashier than what I would normally order. And the last time I ordered one of their cables - for the Dart's kickdown linkage when I found the F-body Super Six linkage didn't fit right - I was upset to find out that it needed fabrication when the ad didn't mention it. But now I'm expecting to do a bunch of fabrication, and Lokar cables are pretty easy to cut to length. I'll have some pictures when the cable arrives.

Labels:


 

A laptop for tuning Megasquirt

I'd intended to save money by tuning my Megasquirt with a secondhand Palm III. However, after seeing this post on the Megasquirt forum, I decided to spend a bit more and get a Panasonic Toughbook CF-27. These things may be outdated, but they've easily got enough power to run MegaTune and the other Megasquirt software. Plus, they're incredibly cheap (I bought mine from this eBay auction - $120 shipped, and it came with a CD-ROM drive!) and built like, well, my slant six. The case is magnesium, and most of the internals are rubber or gel mounted. It feels more like a machine tool than a normal piece of computing equipment. If you need a cheap laptop to tune your EFI, see if you can find one of these on eBay.

Big thanks to T3Bunny for his help - he's the forum's resident Toughbook expert.

Labels:


Wednesday, February 08, 2006

 

Homemade windshield washer fluid - the recipe!

It seems that dozens of people find this blog each week searching for how to make their own windshield washer fluid. Well, I decided to do some digging and see if I could track down an easy to follow recipe. As it turns out, the National Institute of Health keeps MSDS sheets about a lot of household products on line. And most of the time, it appears the active ingredient is simply methanol, as used in Rain-X Ice-X. You can get methanol from an industrial supply house like McMaster-Carr. Currently it's selling for around $16 a gallon plus shipping. A mixture of around 10% methanol and 90% water with a dash of blue food coloring ought to do just fine for even a very icy morning.

The versions with "bug remover" contain a dash of 2-Butoxyethanol. That's going to be a bit harder to track down, but if you're trying to save money by making your own windshield washer fluid, it's something you can leave out anyway.

The whole Household Products Database is useful if you want to try making your own copy of a commercial product. For example, many octane boosters are mostly JP5 jet fuel. And STP Fuel system cleaner is mostly napthalene in kerosene.

Labels:


Tuesday, February 07, 2006

 

The Open Source Car

Here's something I found on AutoBlog: - the open source car! Here is its official website. It seems like a well intentioned project, but I can't quite see how they intend to pull this off. Open source with physical objects is certainly possible - after all, I've got a Megasquirt, which is an open source automotive ECU. But building a car is very different. If it follows standard construction techniques, they'd have to make large sections of it out of stamped steel. Stamping dies can cost tens of thousands of dollars per die. How are they going to get any economics of scale with this? Building a low-volume car can easily result in a car that's comparable to a Geo Metro selling at a BMW 5-series price.

Still, I might join their forums to see if I can contribute a little, just for the fun of it. And because, well, I happen to have some experience on the production end of things.

Sunday, February 05, 2006

 

Why Not to Buy a Chinese Car

There's been a lot of talk in the media about automakers in Communist China preparing to enter the North American auto market. Some have suggested that they may be The Next Big Threat to Detroit - and, for that matter, Tokyo, by undercutting prices to levels that nobody can hope to match. I'm not so sure about that. I've blogged here before about the low quality of tools made in Communist China, and if I care anything about the durability or toughness of a tool, I'll go out of my way to buy American-made ones (or Japanese or European ones, but they're often tougher to find).

I can't help but wonder if the Chinese Invasion is going to be a repeat of the last time a Communist country tried to get a toehold in the United States auto market. In a fit of irony, we even have one of the same importers involved this time, Malcom Bricklin. Is this set up to be a repeat of the Yugo?

Well, the January issue of Mechanical Engineering Magazine has a quote that suggests the answer may be yes. They quote Zhao Jie, president of Geely (one of three Chinese auto makers who seem intent on American sales) with the following line:

In a way we are at a similar situation like Toyota 30 years ago and Korean automakers 20 years ago when they tried to enter the North American market. It will take time for us to catch up in quality. Right now we are trying to optimize our production process and quality control.


While I have to give him points for being candid, it certainly sounds like the Chinese cars they have coming over are likely to be lemons. I'm a little bit surprised that they haven't tried to get a bit more practice at building quality cars for their home market and instead decided to try landing here with a product that's not up to the standards American car buyers expect. After all, the American market is not known for being very forgiving, and while Hyundai and Kia did manage to get established here, many other makers who tried in the past two decades failed spectacularly. While Yugo seems to be the most obvious comparison, other names that come to mind are Daewoo and Diahatsu, who also tried to get in with inexpensive cars that they couldn't sell.

Saturday, February 04, 2006

 

Sold!

It finally happened: I sold the Spitfire. Seems that after my wife had told her boss about it, her boss's fiance decided he wanted a project car of his own. He came by to see it today and decided it was a deal. He plans to have Adam Malley, a nationally known SCCA racer, handle a lot of the mechanical details of the restoration.

I can't believe it's over. On the other hand, there's likely to be another old European vehicle in our future after I get the Dart back together. Stay tuned.

This page is powered by Blogger. Isn't yours?