Miscellaneous hints
or
Some of the things I've learned in many years of building cars.
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First and foremost:

The best place to look for special items you can't find at your local auto parts store is an automotive junk yard.  Actually I go to the junk yard FIRST.

Why? You get some outdoor exercise, you get to measure, handle and play around with the parts, you will usually find a much better and varied selection of items to choose from, and most important, the prices are better.

I have been going to the exact same junk yard  since 1949. I worked there on Saturdays for no pay when I was in high school while building my first hot rod (a 1940 Ford Coupe). They pretty much gave me whatever parts I needed to build it. I've seen the yard go through several different owners.

To get good prices you need to cultivate a good working relationship with the people behind the counter. If they are really car guys (and sometimes, gals) they will probably be quite interested in the fact that you are actually -building- (and not repairing) a car with the parts.

Walk around the junk yard and see how the manufacturers solved pretty much the same problems you are encountering. Look at how things are bracketed and fastened to other parts etc. Wrecked cars can give you an insight as to what worked and what fell apart when it counted. You'll certainly see why seat belts are a MUST!

I've found that if a car is just worn out and not wrecked, that the owner frequently tried one final thing to fix the car. Sometimes that brand new "thing" is just what you can use. Included in that list are alternators, spark plugs, wiring, lights, horns, master cylinders, brakes etc etc.

As a side project, I grade crashes into telephone poles on a 0 to 10 score, depending upon how well the impression of the pole is centered into the bumper and hood of the car! I've only seen one perfect "10" in all the years of researching this. A bunch of 9.9s though. And then there was the one that not only got the bumper, but it made a big impression down the roof too!

Enough philosophical stuff, here's the hints.




"How do you guys bolt the seats to the floor? I'm wondering if the bolt heads end up leaving hex-shaped impressions on one's butt cheeks."
Think short carriage bolts.

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"I need a seat slightly narrower than the 15.5" Kirkey drag seat. What other options are there?"
I use a 15.5" Kirkey drag seat in my 13.5" wide passengers position. I just cut the seat vertically from top to bottom down the seat back and bottom near one of the side seams. Leave about 2" of width of the panel from the side.  Put the pieces into the car and overlap the two parts till the seat fit. Once I got the pieces overlapped to give the width I wanted I clamped them together using some small "C" clamps.  I removed the seat from the car and drilled holes and installed some temporary rivets in the overlap to hold the pieces in place and then stitch welded the seat back together.  Make sure you have whatever mounting hardware (wood in my case) under the seat pieces when you set the width.

There wasn't room for the passengers hips in the available width of the seat so I again cut the seat to remove the sides below the bolsters in the hip area. This allows the passengers hips more room out to the frame tubes. This gives an inch or so more width.  The seat padding on the side will help cushion those areas (but not as good as the original I'm sorry to say).  You have to allow a little clearance for the seat belts to come up the outside of the seat.

I thought the seats wouldn't be comfortable with the stock Kirkey thin padding but I guess the excitement of driving/riding the car cancels out any normal discomfort.

The picture below shows where the seat was stitch welded in three places along the bottom to put it back together.  There are also welds running up the back.

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"What seat adjusters are you using and what changes did you have to make to them?"

I used  the drivers seat adjuster from a 199? Nissan pick up truck.  I made two 3/4" high spacers to go between the front of the seat and the adjuster to angle the seat backwards a total of ~28 degrees. Four 1/4" - 20 carriage bolts are used to bolt the seat to the adjusters and four 5/16" bolts to bolt the adjusters to the floor. I placed a fender washer and a vinyl gasket "washer" on the outside world side of the floor to keep water out.

The chassis width on the passengers side on this car is very narrow and it isn't possible to move the narrowed seat fore and aft. I used two 12" long hard wood spacers under the front and back of the seat to position it the same height as the drivers seat. The passengers seat is cut out on the sides below the bolsters to allow the passengers hips to use the full width between the frame rails. The seat cover provides padding and covers the cut out areas. Both seats are mounted a short distance in front of the rear bulkhead and provide a small amount of storage space behind them.

To see an enlarged view of most pictures, left click on a picture or right click and select "View Image".

Nisson seat adjuster

Bottom view of upside down seat and adjuster.

Note:
This is really the passengers seat with the adjusters laying on the bottom for the picture. The three short welds on the edge of the bottom are where the seat was welded back together after cutting ~2" out of the width. There are similar welds on the inside and up that back side of the seat.  You can see the holes where the temporary rivets were to hold the pieces together prior to welding.  I used quite a few rivets so the metal wouldn't warp while welding.  If you use smooth head rivets you could leave them in after the welding.
The Nissan adjuster was the lowest and lightest I found in the junk yard ($5). The two mods I made to the adjuster were to flatten out the left side where the mounting holes are and I removed some extra metal tabs that were spot welded on the bottom of the adjuster. A sharp chisel got them off OK. In my car the adjuster allows the drivers seat to move a total of ~5".  The adjusters are from a Nissan P/U (late 1990s?). They are light, low and easy to modify to fit.

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"You mentioned that you are using a reverse lock out. What did you make it out of?"

I made the reverse lockout from a 10 speed bicycle gear shifter that has a spring return to the position shown in the photo. I  found one that rotates clockwise horizontally (in this picture) about 90. I cut and trimmed a piece of 1/8" thick x 3/4" wide aluminum strip about 1" long so it could be mounted on the rotating edge of the lever with two small screws. This strip stops the shift lever from going into reverse until the lock out lever is rotated clockwise.

The whole assembly was bolted to the Quaife upper mount sheet metal with 1/4" x 20 screws. There is a small block of wood jambed into the shifter mounting to keep it from collapsing when I tightened the mounting screws. The actual reverse blocking strip ends up just below the upper edge of  the frame rails and is under the tunnel cover out of sight. 

The gear shift lever is made from a throttle lever from a lawn mower. The lower end of it is bolted to the Quaife shifter stub. In this picture the shifter is in neutral. To drive forward you push the lever forward. To go into reverse you rotate the lockout clockwise with the palm of your hand and pull back on the shift lever with your finger tips. It took a lot of planning but it works great.
Reverse Lockout
The stainless steel covered hoses are the fuel pressurized line and the fuel regulator return line. The copper pipe is part of the breather system for the Quaife gear box. The right end of the copper tube is bent down towards the ground and there is a plastic fuel filter on the lower end of the tube to keep dirt out of the Quaife.

You can get an idea of the mechanical knowledge of people looking at the car if they ask you how you back up with a motorcycle engine. I usually don't mention anything about  reverse to see if the person realizes that it is something you have to consider in the the build.

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Need to make an invisible grill in the nose cone to keep rocks, frogs and cats out of your radiator?

Used some 1/4" square galvanized screen mesh and painted it with black Krylon. I also have a piece of unpainted aluminum house screen right in front of the radiator to stop the smaller stuff. You don't notice the house screen because it is so far back inside the grill opening.  If you mount a "7" in the grill opening on the screen mesh it looks like it's floating in the air.  For racing I'd leave the solid "7" off for maximum cooling.

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"What can I use to make an exhaust system that won't rust out or turn blue?"

Try some stainless steel tubing from a swimming pool ladder. It should be TIG or MIG welded though. To keep the bare pipe from turning blue when you run the engine (unless of course you LIKE parts of your exposed exhaust system to be blue) try this.

Before you mount the s.s. exhaust system, smear some grease inside the pipe (start at the end of the pipe closest to the engine) and try to coat at least the first foot of the pipe with the grease. I use a piece of coat hanger with a small strip of rag fastened on the end. Sort of like a rifle cleaning patch. Smear some grease on the rag and work it around inside the pipe as far as you can get it to go.

What happens is that when you first run the engine the grease will burn away leaving carbon or soot on the inside of the pipe where the bluing is likely to form. The soot then insulates the inside of the pipe from the extreme heat and usually it doesn't get hot enough to turn blue. This is an old motorcycle trick.

You can read more about the exhaust pipe here.

 Exhaust pipe


"Where can I get some of that corrugated plastic stuff that is used to cover the wiring? Or where can I get a large grommet to feed the wiring through the firewall?" Or where can I get ... (all sorts of special automotive clips, fasteners, chrome acorn nuts, carpets, etc etc)

 I have always found these items at my favorite junk yard.

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"Where did you get the red battery cable?"

I found a lot of AWG #4  power cable which is used on remote audio amplifiers at (you guessed it) the junk yard. It easily handles starting a BEC. It comes in several colors and was cheap too. Don't use the AWG #8 cable. It's not rated to handle the current required for starting the engine.

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"How did you fasten the rear fenders on?"
I used 1" long 1/4" x 20 threads per inch hot dipped galvanized hardware. I also made some 3/4" wide x 1-1/2" long by 0.100" thick aluminum "washers" to spread the load out on the fender fiberglass flange and another one on the inside of the body. Where there wasn't room for the washer on the inside of the body I used cut down cadmium plated steel washers instead.

The first bolt hole is about 1-1/2" up from the bottom of the front end of the fender. I spaced the remaining four bolts approximately 7" apart. On my car the area between the curved strap by your shoulders wasn't filled in. The metal was just floating in air. Since my car was already powder coated from CMC I was reluctant to weld pieces of  metal in place. What I finally did was cut some non-porous stiff foam to fit in the gap and used some black RTV to hold it in place. I also smeared the RTV all over the foam to waterproof it.

I made 1/4" x 20 threads per inch "J" bolts from some threaded rod for the fender mounting bolts that are positioned in the foamed area. The "J" portion of the bolt loops over the flat strip and the threaded part of the bolt angles slightly down towards the back wheels as it extends outward through the foam to the fender flange.

The rear of the fenders didn't quite match the contour of the body. I riveted a short length of aluminum strip to the bottom lip of the fender and used it pull the bottom of the fender onto the body. The strip was formed to go around the lower curved frame tubes and a sheet metal screw through the tube holds the metal in place.

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"How did you get the speedometer sensor to work since the drive shaft adapter and the U-joint covers the original sender part?"
I used four hardened long bolts to attach the front U-joint flange to the adapter. The threaded portion of the bolts go through the adapter and project about 1/2" beyond the flange towards the transmission. I mounted the original Suzuki sender so that the bolts pass about 0.015" from the sensor. The Suzuki sender has a magnet in it and it senses the four bolts as they by pass the end of the sensor.
speed sensor
The sensor is the rounded object just to the right of the drive shaft adapter flange. The bracket is above it and is bolted to a spare threaded hole in the engine casting.

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"What speedometer corrector are you using?"

I bought an electric speedometer corrector kit from Jaycar in Australia for $30 delivered. The kit number is KC5435. It was very simple to put together and works great.  At the time I bought my corrector it didn't have a case so the next question may not apply anymore.

You can find it here;    http://www.jaycar.com/index.asp

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"What did you use as a case for your speedometer corrector PC board so you could still open it to adjust the correction?"

An "Altoids, Curiously strong Cinnamon mint" container. It's just right for a Lotus replica (also made in Great Britain) and it has a hinged cover too. I mounted it above the pedal area on the drivers side of the firewall with 4 pop rivets. And the candy is pretty good too.

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"How do you tap a hole in tubes or thick metal. I broke a few taps already"

If you haven't done this already, I would suggest that you buy a good set of taps (once) and treat them with care. I've been using the same Craftsman tap/die set for at least 30 years. I've broken one or two of the 1/4" taps and dulled a tap or two but that's all.

Forget the Harbor Freight type stuff. I bought a Metric set to do a few holes and the taps turned out to be softer than the ordinary metal I was trying to tap. If the taps are a black color from Harbor Freight you might as well use a nail as a tap.  I hear some of their drills are just as good (not).

Probably the most important thing is to make sure you use the right size drill for the hole to be tapped or even a lettered drill a few thousandths oversize if the tap doesn't want to start correctly.

As for lining up the tap for deep holes. I use one of two methods; my drill press or the lathe.

If you are tapping a tube try this; I have a small machinist vise bolted to a rotary (adapter) table which is in turn bolted to my drill press table. The vise has a small "V" cut horizontally into center of the jaws. I put the tube which already has a center punch where I want the hole to be so the punch mark is centered vertically in the "V" cut and then tighten the vise just enough to hold the tube steady.  Don't tighten the vice too much or you may warp the tube.

I then put the correct drill for the tap hole  and move the rotary table around so the punch mark is centered directly under the drill.  Once the hole is drilled put the tap in the chuck and  DO NOT TURN THE DRILL PRESS ON WHILE TAPPING THE HOLE !

Put a few drops of thread cutting oil near the end of the tap and slowly lower it down and turn the chuck by hand to start the tap into the tube. As you turn the chuck you will feel the tap being drawn into the tube as it starts threading. Lower the chuck with the handles while you hand turn the chuck for a bit and then loosen the chuck and then either use a tap wrench or a 3" crescent wrench to continue taping the tube.

As for clearing the cutting chips I usually back the tap all the way out if the tap is more than 1/2" or so into the metal [in a blind hole]. I use a tooth brush to clean the chips off the tap. Apply a few more drops of threading oil and run the tap back into the piece to be tapped.

As far as running the tap out. It won't be cutting threads in reverse since the threads have already been formed when you were running the tap INTO the hole. But the chips can bind up in reverse sometimes. So use care when backing the tap out. If the tap feels hot, go take a break and let things cool off (it will probably be cutting oversize threads while hot or certainly trying to lock up).

You can also more less do the same procedure with a lathe instead of the drill press. It's a lot easier with the lathe since everything is normally already lined up.

DO NOT TURN THE LATHE ON!


Chuck the piece to be threaded in the rotating head (3 jaws for round stuff, 4 jaws for strange shaped things, center the hole with 4 jaws), after drilling the tap hole put the tap in the tail stock chuck, move the tail stock towards the chuck so the tap starts into the hole (don't tighten the tail stock clamp) and rotate the head CAREFULLY by hand. The tap will be pulled into the hole as you start to tap it.

It takes practice to get the feel of how much stress the tap can take. Until you figure it out, as soon as the tap starts to bind up, STOP and rotate the head in reverse to back the tap out and clean it. If the tap doesn't want to back out, work the head back and forth maybe 1/8 of a turn till you can get it to come out.  You may have to let the tap cool off before you can get it to back out.

It's the same as how you get to Carnegie hall, "Practice - practice".

(It turned out the guy was trying to use a self tapping screw as a hardened tap and it didn't work.  :-(

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NOTE: This is a work in progress and items will be added as I think of them (or someone asks me "How/what/when/where........").



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