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Car Corner
The Tune Up

June 1, 2003
By Scott Lewis

I wanted to get a couple of months of really good driving out of my 67 Camaro Convertible before I sell it. So I decided to do a complete tune-up. I am still trying to decide if I want to fix the four items I am concerned with for the sale. The left headlight door motor, the neutral safety/backup light switch, the rear window and the heater core all need to be replaced. I have the heater core, but don't know if I want to go through all the trouble to take the dash apart to install it. After all I don't drive the car in the cold anyway.

The Basics

Doing a tune-up on a 36 year old car is not difficult. It is mostly a matter of remembering all the little things you need to do. Here are the basic components you need:

Spark Plugs
Plug Wires (optional)
Points & Condenser
Distributor Cap & Rotor
PCV Valve
Fuel Filter
Air Filter

All of these parts are basic remove and replace items, except the points. Old cars use points to determine when the coil should send a charge through its main wire into the distributor cap. The rotor then directs that charge to the appropriate spark plug wire. The gap of the points needs to be set, and the dwell (the amount of time the points remain closed) must also be adjusted. It has been a very long time since I have adjusted the points on a car.

Crane XRi Electronic Ignition Module

I decided that I wanted to try out Crane's new XRi electronic ignition conversion kit. I know it seems like a waste of money if I am just going to sell the car, but here me out. The Crane module is an electronic device that mounts in place of the points inside the distributor cap. It is very simple to hook up. It uses two wires. One goes to the negative side of the coil in place of the wire from the points. The second wire goes to the positive of the coil or to a 12 volt source depending on your specific application. My application has an external ballast resistor (to reduce the voltage going to the coil). As such I needed to provide a full 12 volts to the Crane module. I ran the wire to a 12 volt switched ignition source right on the fuse panel. This was better than trying to find a wire that met that criteria. (The instructions tell you how to determine which way you need to install the unit.)

Other than that the Crane unit is a breeze to install. I did have to remove the distributor to install the Crane unit. The wire from the points went through a hard plastic grommet on the bottom of the distributor. It was impossible to remove this grommet and run the new wires through that hole with a new grommet while it was in the car.

I marked the position of the rotor before pulling the distributor. I was planning on using my timing light to adjust the timing anyway. I installed the crane unit and put the distributor back into the car.

At this point I installed the old rotor and put the cap back on. I started the engine to make sure it all worked before I replaced all the other components. I set the initial timing to 10 degrees (stock is probably 4, more later). The vacuum advance on the distributor moved quiet a bit and the hose was not long enough. I went to the parts store and picked up a new hose. When I went to install it it was too large. Apparently one side of my hose was smaller than the other. Oh well, back to the store for another hose.

By this time I was getting frustrated with not being able to drive the car, so I buttoned it up and started driving it. I am glad I did. The car started easier, idled smoother and generally seemed to run a little better with only the electronic module. I would not have noticed this had I did the complete tune-up all at once.

The Tune Up

Now it was time to dive in and replace everything. I replaced the fuel filter, put in the AC plugs gapped to .035", and ran new ACCEL wires to a new ACCEL distributor cap with a new ACCEL rotor. I know the wires, cap and rotor are not stock, but neither is the Crane electronic ignition module or the TH350 transmission. The wires and cap are black, like the ones I removed, so they don't stand out. And the price was right at less than $40 for the wires and less than $10 for the cap and rotor.

I had bought the PCV valve, but the one on the car was treaded while the new one was not. So I skipped this for the time being.

While I was doing all this I added another modification. I added a Mr. Gasket ignition advance kit. This replaces the stock weights and springs in the distributor with heavier weights for more advance, and lighter springs so the advance comes in sooner. This improves the performance of the engine as long as the engine can tolerate the extra timing without detonation. All has been good so far. The initial advance of 10 degrees with the extra advance from the Mr. Gasket kit will improve part throttle response and make the engine more lively. With the low compression of this engine I really doubt I will have any issues with detonation.

Finally, before installing a new air filter I ran the engine and sprayed a bunch of Gumout carburetor cleaner through the carb.

Oil Change

Why bother to go through all this trouble and not replace the oil filter. However, the 67 Camaro uses a canister style oil filter. I bought a Perma-Cool oil filter adapter that allows the car to accept a standard spin on oil filter. This was much easier than dealing with the canister, and will make future oil changes a breeze.

Speedometer Gear

When I installed the TH350 transmission in November 2002 the speedometer was off about 14%. I replaced the gear in the tranny with one I got from the mechanic that built the tranny. As of posting I had not had a chance to determine the accuracy of the speedometer. I'll post something in the future.

Conclusion

The car is running great. The power is up a bit from before, and responds much better to stabbing the throttle. The engine is running about as close to perfect as it can. I have better wires that are less likely to wear out and I don't have points that wear out, so the car should run better for longer periods of time before needing a tune-up.

Also, I will make all the changes to the car a plus for selling. The electronic ignition is more reliable and accurate than old style points. It fits in the stock distributor cap, so no one has to know. The spin on oil filter also makes oil changes far easier both in operation and getting the replacement filter (it now takes a common PH30 Fram filter). Even the TH350 transmission is far more reliable than a Powerglide. You just put it in drive and off you go. But now it has a good passing gear to make driving on the freeway that much more fun. Of course, I have saved every single part I have removed from the car should the next owner more of a purist.

To the casual observer the car still looks all original, but it is more enjoyable to drive. More importantly, it is far more enjoyable to maintain which should lead to more driving time. Now that's what counts in a classic convertible.

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