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1969 GT350 Alignment specifications

Started by Dan353, May 25, 2020, 05:11:04 PM

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Dan353

I was wondering what alignment specifications everyone is using for a 69 GT350?   The upper control arms have not been lowered and I have 235 60 15 BF Goodrich tires. My car is mostly street driven but I do take it on the track also.  My reason for asking is I have been told several times that the specs in the manual aren't good for radial tires or track use.  It seems that every place I look all have different spec's and at this point I'm just getting confused about what alignment specifications to use.   Thanks in advance for any help.

Dan

The Going Thing

Unless you lower the control arms the specs are not different. The only thing I have ever noted is that some change the toe adjustments for track use.
I wouldn't bother if your primary use is road use. There are trade offs for some adjustment, which is accelerated wear. Tire size has no relevance on adjustments.

Now onto the most difficult part. Finding a competent shop to do the work. It took me three shops.  National Tire forgot to tighten the cam bolts after the alignment. Be particular about where you take it and I suggest you don't leave it.

shelbydoug

1-1/2 to 2 degrees + castor, 1/2 to 3/4 - camber. 3/16" toe in. 32psi cold in the tires.
68 GT350 Lives Matter!

The Going Thing

Quote from: shelbydoug on May 25, 2020, 07:43:38 PM
1-1/2 to 2 degrees + castor, 1/2 to 3/4 - camber. 3/16" toe in. 32psi cold in the tires.
That's about the spec for the lowered A arm cars. If I remember right, you have the lowered arms too, right Doug?

shelbydoug

#4
Yes but you use the same specs. It doesn't change.

The lowered a-arms are for changing the way the car rolls through the turns. It stays flatter.

The only thing that you might want to change would be the camber. It depends on the tire.
Some tires like -1/2 degree, mostly bias tires. Radials like more but if you go with too much air pressure the tire starts to act more like a bias tire since it won't roll as much which is what gives a radial more grip in cornering.

By comparison, a full comp set up might be as much as -3 camber and 5 or 6 + castor?
Toe in stays basically the same at min 1/8" max 1/4" toe in but you set the toe off of the wall of the tire and is always an approximation. No need for NASA digital alignment equipment.

NASCAR uses power steering assist now. Back in the day it was strictly manual and you threw the car into the turn to help you turn the wheel, steering with the throttle so to speak. Steering through turns with that much castor is difficult.

You need lots of castor on a long track to keep the car going straight and much less on a small track. So the setting varies according to the track and you need to determine that on practice day.


For a street car you don't need a lot of anything. The biggest change is going to be from the camber change.

Tires in the day were the limiting factor. The best tires were just plain terrible and camber was set at zero rolling off of the production line because in most cases it just didn't matter on street cars


Just for the sake of discussion, Ford built -1/2 degree into the rear axle along with a 3/16" toe in. If they didn't the car would be unsafe to drive.
68 GT350 Lives Matter!

Dan353


mikeh

Suggestion: Go to www.hunter.com, click on contact Hunter & see who local sales & service reps are. They should be able to recommend a local shop with the right equipment & mentality to align classic cars, there is a big difference in shops!!

Dan353

I'm doing the alignment myself I'm sick of taking my car to shops that do bad work or think I'm rich and try charging me $300 for an alignment they quoted $100 for than in the middle of the job say that the $100 was for the first 1/2 hour. And all the guy did was drive it on the rack and put the equipment on.  I've had a few shops do this to me over the years.  Sorry but it's aggravating

Dan

shelbydoug

Quote from: Dan353 on May 27, 2020, 06:35:04 PM
I'm doing the alignment myself I'm sick of taking my car to shops that do bad work or think I'm rich and try charging me $300 for an alignment they quoted $100 for than in the middle of the job say that the $100 was for the first 1/2 hour. And all the guy did was drive it on the rack and put the equipment on.  I've had a few shops do this to me over the years.  Sorry but it's aggravating

Dan

Most racers do their own alignments. I do. It's easy once you learn how and you learn a lot by doing your own. Go for it.
68 GT350 Lives Matter!