Re: Need Front end alignment specs for a 1970 Nova
Assuming this is a street driven car. I have probably aligned several hundred old Chevy's of every kind up until 1988 or so. The official factory specs for a 69 Nova are:
"Caster 1/2 degree pos + or - 1/2 degree
Camber 1/4 degree positive + or - 1/2 degree
Toe 1/8 to 1/4"
Neither caster nor camber should vary more than 1/2 decree side to side."
I would be amazed if the 70 specs are any different, seeing they were on the same chassis.
Now, having given the specs, I can assure you that you can align the front end within those specs and be quite dissatisfied. Why? Firstly, just too much variance allowed. Secondly, the car will tend to "pull" to the side with least positive caster and with most positive camber. You can see where this is going. If there is any variation on caster, make sure the left side is slightly less. Opposite for camber. This will compensate for road crown.
There are some other things to consider.
1. Are you running the factory wheel? If you are running a wheel with a different width and or offset, the "factory" specs don't do you a lot of good. If you put headers on the car, you will need to rejet the carb at the very least. Same thing applies to tires and wheels.
2. Are you running bias ply tires? If not, again, forget the factory specs. Bias ply tires require much more camber to be able to interact with the road than radials.
3. Do you have power steering? If so you can benefit greatly from increased caster. GM used the same specs for both manual and power steering (except on Corvette) and had to use very little caster because the manual steering cars would have increased steering effort with greater caster.
4. How new are your front end pieces, i.e. ball joints, tie rods, idler arm etc.? The main reason for toe-in is to counter the tendancy of a car to "toe out" while going down the road, especially during braking. The better shape the front end is in, the closer you can run to 0 toe. Radials also don't need as much toe in. Run 1/4" toe on a set of wide radials and you will quickly feather the outside edges.
When my 69 Camaro (same factory specs as a Nova) is done, I will have one set of old bias plys for shows, but when I want to go drive the dog out of it, I will have a good set of radials. My specs will be as follows:
Caster 3 degrees positive Sometimes not possible, but usually not a problem. If you can't get to 3 degrees, put in as much as you can while still keeping the sides matched.
Camber 0 (really with the left side just on the plus side of 0 and the right side just on the minus side of 0 to compensate for road crown)
Toe-in 1/32 to 1/16 MAX
Hope this helps.
Back in the 70's I worked at a Buick dealership for a couple of years. The parts guy had a friend who regularly autocrossed his Corvette. He had taken it to several "specialty" shops for alignments, but never thought it was just right. It had wide wheels and wide radials (for the day) and when I checked it out is was spot on the factory specs. After I checked to make sure all the parst were tight, I aligned it front and rear putting in more caster and slightly negative camber in the front, even more neg camber in the rear. Set the to just a shadow in from 0in the front and right on 0 in the rear.
The guy came back the next week ecstatic. He had for the first time beaten his nemisis over the weekend, with no other mods.
Lynn
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