Wednesday, June 24, 2009

My Previous Ride: Toyota Kijang Pickup 1991

The Dog isn't my first car. I had two rides previously, both were Toyotas. The first was a '77 KE30 Corolla. My dad bought me that car when i was still in high school. It got funny problems like all the lights would turn off after 10-15 minutes turned on, AC was more like a heater and the brake was awkward. Even with all those problems, i was very proud of it since it was my first car. My dad got it repainted and slowly fix those problems.

This is a story of my second ride. My mom started a wedding decorations business when i was in university and needed a pickup truck to help her move all the decorations to the wedding places. We decided to sell my Corolla and get a Toyota Kijang pickup.

It was '91 Toyota Kijang pickup, the third generation of the Kijang family. From wikipedia, i found out that it was sold as Toyota Unser in Malaysia, Tamaraw in Philipines, Qualis in India and some other countries.

First time i got it, it was white and ugly. Unable to restrain myself any longer, i decided to do some makeovers. These are some of the things i did:

1. Painted it "Metropolitan Blue" color by Danagloss. This was the same color i painted my Corolla with. I guess i just love blue so much. Heck, maybe i'll paint The Dog blue also.

2. Attached a pair of tail-lights taken from the van version of my car.
3. Actually, i had 16 inch rims attached which was repainted to white (original color was silver) but one day i had an offer i can't refuse ... 18 inch Taiwanese rims with 95% condition used tires for only 3.8 million Rupiahs (which is around $400). The rims are what you see on the pics.

4. Also put on a new grille, front bumper, headlights etc which was also taken from the van version. I painted the grille bars black myself using spray paint.
5. As for the 5K - 1.5 liters engine, i didn't do much except putting Pertronix Igniter system, Pertronix ignition coil and Hurricane spark-plug wires. Actually i also oversized the cylinder by 0.5mm but i don't consider it as modification ... I just did it because i have to (c'mon ... you don't expect a 15+ years old engine to be running as it should be, do you?). I also removed the belt-driven radiator fan and replaced it with an electrical one.
6. As for the audio system, i put on a 5.1 system computer speaker set made by Philips. The speaker set was the MMS series. It has a power supply plug which needs a 13.8 VAC supply but, believe me, you can plug a 12 V DC car electrical supply straight-in. That is because actually the 13.8 VAC will eventually be rectified into a DC supply inside the speaker... Heheh, 4 years of college really did pay off. I used an MP3 player for the source which plugs straight in. However,that meant i only had a 2.1 system running ... I made a 2.1 to 5.1 converter but it ran on battery. I didn't have the time to change it to run on car battery. I was very proud of my soundsystem. The speaker set only cost me about $60 and the 1 Gigabyte MP3 player was around $50.You get a complete car soundsystem for only $110!

7. I put on a Tachometer from Autogauge. They are cheap but they didn't show the correct RPM. I had to set it to 8 cylinders so that it showed to correct RPM for my 5K engine.

8. I also put on an Air/Fuel Ratio meter from Autogauge. For those of you who understand that putting AFR Meter is not common for carbureted engine, then you know that it requires some trick. Usually AFR meter is put on a Fuel Injected car with closed loop system (having an O2 sensor). I just had to buy an O2 sensor and attached it on my exhaust pipe near the header, wire the AFR meter to it and it works! What good did it do? Well, i found out that i could reduce my primary main-jet to acquire the best AFR. That means less fuel and better mileage! I also know on what RPM i should run my car to get the best AFR and thus the best mileage also.

9. I put on Suzuki Jimny turn-signal lamps on Daihatsu Espass side-view mirrors. Granted, the lamps were too short but i didn't get any better candidate.

10. As you may have noticed, i custom-made a bed-cover for it. It was made from two 0.9mm aluminum sheets with iron bars as the frame. I used door hinge on the left side and two wing nuts on the right side to keep it closed. If i wanted to open the cover, i just had to unfasten the wing nuts. It cost me near $40 to make the bed-cover.
I kept the pickup for more than 4 years and sold it a few months ago. I was very sad when it was sold. So many memories were made with that truck. Even my girlfriend was sad also because it accompanied us on our dates. Well, sadly, keeping it would be too much hassle due to the way i work, moving from one city to another. Besides, i think it's about time for me to get my own car. So i made up my mind to sell it. Now, i am ready to make new memories with The Dog!

Sunday, June 21, 2009

DIY Dashboard Panel Part 2 - Low Fuel Warning Circuit

Since i failed to find a 2-inch fuel level gauge that looks similar to my other gauges, i decided not to install it. However, since i still need to know if i have enough fuel, i need some kind of warning lamp to remind of of low fuel volume. Actually, i was surprised why didn't i think of this before. This is much useful than a fuel level gauge. I don't need to know how much fuel left in my tank, i just need a reminder for me to fill up the tank so a warning lamp is the way to go! It takes less space and it should cost less to build.

Fuel level gauges are actually amp-meters. It measures the variation of current caused by varying resistance in the fuel level sender. It all goes down to the Ohm law:
Voltage = Current x Resistance
where voltage should be constant somewhere around 12 volts.

There could be slight variation but basically, the circuit is wired as such:
If you've worked on fuel tanks before, you'll see an arm attached to a floater on the fuel sender unit. This floater will always float on the surface of your fuel. Thus, it would be high on full tank and it would be low on low tank. The arm is attached to a pointer which... uummm.. points to a certain position on a resistive material, which could be a wire wound or a simple carbon track. So, for those familiar with electronics, a fuel level sender unit is basically a potentiometer. Below is an example of a fuel level sender unit.
In short, it works like this: fuel volume --> floater position --> pointer position --> resistance --> current --> amp-meter! Real simple, right?

The problem is, the resistance in the sender varies between makes and models of the car. I need to know what is the resistance for both full and empty position in Daihatsu Charmants. A dude in the local Daihatsu Charmant mailing list told me that there is a "KE70" writing on the fuel level sender when he opened up his Charmant tank recently. So i'll assume the sender unit is the same with Toyota KE70s*. Upon googling, i found that Toyota KE70 fuel sender unit spec is as follows:

empty = 3.0 +/- 2.1 ohm
1/2 = 32.5 +/- 4.8 ohm (float is 28.5 degrees off empty)
full = 110.0 +/- 7.7 ohm (float 57 degrees off empty)

putting those values into a graph, it would look like this:
So, as can clearly be seen from the graph, the sender is a non-linear variable resistance. Now this is important: determine at what fuel volume would you like your warning light to turn on? I decided on 25%. At 25%, the resistance on the sender would be in between the ohm at empty and at 50% fuel volume. Although it's non linear, i'll just assume the value using the average ohm value since it's not really crucial so (3 ohm + 32.5 ohm)/2 ~ 18 ohm. So what i need to do is design a circuit which would turn on a light when the fuel level sender is below 18 ohm since that means the fuel volume is less that 25%.

To achieve aforementioned purpose, i'll use a cheap LM741 IC. LM741 is an operational amplifier (op-amp) which has 8-pins dual-in-line package. Discussing how op-amps work would really be boring (as if this post is not already boring!) so i'll skip it and go ahead to the circuit design:
The LM741 inverting input is connected to a reference voltage (which is 6.8 volts as determined by the Zener diode). The Fuel Sender and Rx forms a voltage divider and connected to the non-inverting input. At above 25% fuel volume, the voltage on the non-inverting input should be higher than 6.8 volts so the output will remain high which keeps the lamp unlit.

Now, we will determine the value for Rx. At 25%, the fuel sender unit will measure 18 ohm. This resistance value combined with Rx should form a voltage divider which outputs 6.8 volts. We'll assume the supply voltage as 12 volts. Using voltage divider principle, we can determine Rx as follows:
6.8v / 12v = 18ohm / (18+Rx)ohm
Rx = 13.76 ohm.

I think the closest available resistor value is 15 ohm so we'll use it.

A note on the lamp: i don't know how much current can the LM741 sink on the output pin. So be safe and use the least wattage you can find for the 12 volt lamp. A 3-watt 12 volt lamp would flow 250mA on the pin and i think it's already too high for the LM741 to handle. You can use a PNP transistor driver before the lamp just to protect the LM741. Other way is to use a LED with resistor..

All of those components should cost very cheap and can be put inside a small housing. So, start heating that soldering iron and enjoy the smell of tin and resin..

I'll update this post when i have finished soldering.

(*) = While upon ACTUAL comparison, the fuel level sender units look different between KE70's and Charmant's, i am willing to assume that the resistance spec is the same. A clue is better than a wild guess, right?

-------**** update 22-Jul-2012 ****--------
Apparently i got the wrong info. After i pulled out my own fuel level sender and measured the resistance myself, the sender works the other way around: low resistance at Full and high resistance at Empty. 10.3 ohms and 113.1 ohms, respectively. This means, the fuel level warning circuit needs to be altered a bit by swapping between Rx and the fuel level sender.

Saturday, June 20, 2009

Update 20 June 2009

At least one third of my rear door panels was replaced with new plates. The workshop owner decided giving up on hunting new rear doors and worked on the old ones instead. Here you can see the results.
I am considering on overhauling my 4A-GE instead of putting it in the Dog directly. This way, i can also start working on inverting the intake plenum so that it faces front. Hopefully, i can save engine conversion cost this way since i'll be doing some of the work myself.

Tuesday, June 16, 2009

DIY Dashboard Panel Part 1 - Panel Design and Item Placements

I am making a custom dashboard cluster panel for The Dog. I'll try my best to document the whole process starting from the design until the cutting and finishing. This would be the first DIY post for this blog. Hopefully it would be useful for you.

This DIY guide will be divided into some parts. Do excuse me since I am too lazy to plan out the parts so i'll just add them when i feel necessary. This would be Part 1: Panel Design and Item Placement Planning.

I've done a mockup for my dashboard panel design. Below is the design. Click on image for better view.
As can be seen above, there are quite a number of items to be put on the panel. I am going to describe each of them together with the function below. There are three types of items on the panel: gauges, switches and lamps. I'll start with the gauges from left to right

Oil Pressure
You shouldn't drive with low oil pressure or you'll be overhauling your engine in a short time. Focus on replacing your oil pump anytime you see low oil pressure.

Oil Temperature
Indicator of how well your cooling system is performing. Low oil volume can also cause higher oil temperature.


Measures the vacuum in the intake manifold. Useful if you want to save gas money. Keep it on high vacuum and you'll get good mileage. There's a good explanation on vacuum reading here.

Tachometer w/ Shift Light

Shows engine revolutions per minute. A shift light is useful for either fuel economy or during those occasional weekend drifts just so you can focus on the steering works.

Air/Fuel Ratio
Also very useful to achieve good mileage. There are two types of AFR meter: narrow band and wide band. Mine's a narrow band. Keep the needle fluctuating between rich and lean to get a good mileage, since that's when you're driving on a stoichiometric gas/air mixture where all gas are burned and none is wasted. There's a good read on AFR here.

Water Temperature
Also an indicator of cooling system performance. Don't drive on overheated engine. Enough said.

I don't know why i am putting this gauge. This is not very useful other than monitoring your battery charging system, which should fail very rarely. Maybe it's just there to keep it symmetrical, three 2-inch gauges on the left and another three gauges on the right. Honestly, if i can find a fuel level gauge that looks similar to the other gauges, i'll replace the voltmeter with it. The problem is i can't.

Next comes the indicator lamps.
Check Engine Light (CEL)
CEL hooks directly to one of the pins on my 4A-GE ECU. I shouldn't see this turning on when my engine is running if everything is normal.

Low Fuel Warning Lamp

I put it there since i failed to find a fuel level gauge. This is the most difficult item to put since i have to make a small electronic circuit using IC and some other components. I'll design it to turn on if the tank is approximately 75% empty.

Turn Signal

Charge Lamp
If my charging system is OK, this should be off when the engine is running

"Hmmm why's the car running awkward? WTF! I forgot to release the e-brake!"

Is there any other indicator lamp i should be putting there? Do remind me if i forgot something. I don't put high-beam light since there isn't much use to it.

Last comes the switches..
Ignition Switch
I should turn this on first before cranking the engine. Pretty much an engine kill switch..

Radiator Fan Bypass Switch
Useful if my radiator fan thermoswitch is faulty or on those stop-n-go traffic jams. Keeps the radiator fan on all the time which is way better compared to an overheated engine.

Fuel Pump Switch
I should also turn this on before starting the engine. It's there for safety reason. Who knows if i am going to be in a very bad accident. This would prevent the fuel from leaking to the engine bay and.. well you know.. KABOOM!

Notice that i decided to put these switches waaay on the right side of the panel? The reason is that I don't want some smart ass sitting on the passenger seat to easily reach and play with these switches while i'm driving.

I also decided not to put a battery cut off switch on the panel as it is too bulky and would take up too much space on the already cramped panel. I also don't put a speedometer (and subsequently, an odometer) since i don't see it very important. What about oil changes, you say? I'll hookup an engine hour meter so i'll replace the oil based on how long the engine has been running, not on how far the car has traveled.

Sorry for the lack of pictures on this post.. I couldn't put pictures of each gauges since i am using a black face type of gauge which is hard to see with the internal lamps off.

The second part of the DIY Dashboard Panel would be how to hook up these items. That would be one very long post so be prepared..

Friday, June 12, 2009

Car Security Ideas: Steering Quick Release & Shift Light

I bought some more goodies recently. First one is a Steering Quick Release hub. This is no Sparco or any of your usual expensive brand stuff. I can't say what brand it is since it's not written anywhere. I got them online for quite cheap, less than USD35. At first i was afraid of the quality, that it would not hold the steering firmly. I was wrong. It's got quite a grip. Now i just hope it will hold up for a few years.
I also succeeded on my tachometer hunt. On my previous post, i mentioned that i was looking for a 3-3/4 inch tachometer for me to install together along with the other gauges i have. I found someone selling a used one online for 25 bucks. I once asked for a new one and they offered me one for 65 bucks! Quite a saving, i'd say. Anyway, here it is, an Autogauge tachometer with shift light.
Do you know that you can have a good car security system out of the two stuff above? You know where this is going, don't you? The first one is the famous, Mr. Bean inspired, steering wheel removal method. Unless car thieves start bringing their own steering wheel, i'd say this is the best car security system ever! Seriously, this is one of the reasons i bought the hub. Well, i won't be bringing my steering wheel anywhere i go so again Mr.Bean's episode to the rescue: i'll hide it in my trunk!

Now, the second one is less ghetto and requires more effort. Using the shift light on the tach, hook the light to drive a relay to the ignition system. Lower the triggering rpm to about 1500 rpm and you're done. Now if the thief manages to get in your car and start it, each time he accelerates, the car engine would stall. Each time you want to drive the car, just set the shift light to maximum like 11,000 rpm so you won't trigger the relay or be safe by unhooking the relay via hidden switch. Of course, you need to consider whether the shift light circuit can drive a relay directly or you need a transistor in between.

Friday, June 5, 2009

Hotwheels Datsun Bluebird 510 Investment

I don't know why but I bought this a few days ago.
I guess it was just a crazy thought that one day this will be an expensive collectors' item. Who knows how much it worth years from now. Well maybe not that expensive since JNC wrote about this particular Hotwheels saying how successful this model sells. Anyway, i'll do my best not to open up the box so as to keep it as mint as possible. I'M RICH!

Gosh, aren't 510s just beautiful? Surely it's right up there on the list of sexiest cars ever (together with Charmant, of course.. :P). Man, i am sooo building myself a 510 someday!