65 Wheel Alignment and Tune Up Specs?

[Sheldon Sands (31959)]

I have a 65 coupe with the 350HP L79 motor and am wondering what is recomended for tune up specs for timing on this motor. It is completly stock as per the orignal motor specs and has a 4spd tranny behind it.
Also wondering about alignment specs, i have replaced the rear spring with a reproduction from corvette central and the car has radials on the orignal wheels. They are 205/75R15 tires. Do I use the orignal specs as per GM or should I do something different? Have just finished a complete 3 1/2 year resto and have put about 50 miles on it and would now like to get everything tuned up!
Thanks in advance.
Sheldon

[Michael Ward (29001)]

65 Wheel Alignment

Use the specs for 1973 and up Corvette. '73 is the first year these cars came with radial tires.

[John Hinckley (29964)]

Re: 65 Wheel Alignment and Tune Up Specs?

Sheldon -

Base timing (vacuum advance disconnected and plugged) for a '67 L-79 is 10 degrees BTDC - the '65 should be the same. Although the '65 and '67 distributor part numbers are different, both have the identical centrifugal advance curve (0* at 900, 15* @ 1500, 30* @ 5100), and the same vacuum advance specs (0* @ 4" Hg., 16* @ 7" Hg.).

[Duke Williams (22045)]

Re: 65 Wheel Alignment and Tune Up Specs?

Radial tire TOTAL toe-in should be established at 1/16", front and rear. At the rear it is very important to have the total toe-in equally divided between both wheels, and modern four wheel alignment equipment should be able to accomplish this.

I recommend the following alignment specifications, and the settings should be as close to equal side to side as possible. These settings should be made with the car at curb weight, which would include fuel to capacity and ride height within factory specifications (front "Z" dimension and rear "D" dimension) as listed in the appropriate sevice manual or AIM.

TOURING SETTINGS

front camber - zero degree
front caster - 1.75 degrees (2 - 2.5 degrees with power steering)
rear camber - minus 1/2 degree

PERFOMANCE SETTINGS

Front Camber - minus one degree
Front Caster - 2 to 2.5 degrees
Rear Camber - minus one degree

With the performance settings I highly recommend hard urethane bushings on the front anti-roll bar end links, and also recommend them with the touring settings.

Greater caster improves on center steering feel, but results in higher steering effort, particularly at parking lot speeds. In general, the higher the caster the better the steering feel at road speed, but the tradeoff is higher effort at very low speed.

If you have wide wheels and tires on your car, negative camber settings will provide more outboard fender clearance. Changing camber about one degree in the negative direction will move the top of the tire inboard about one-quarter inch.

Duke