# what is correct or average caster spec for 67 gto



## fiesta62 (Jan 12, 2011)

hi...i had my 67 gto wheel align done today, i have new ball joints, taller ball joints on top than standard, done all bushes and wheel bearings, i have read on these forums that 4 or 5 degree positive caster is the go, i got 1.35 positve on both sides, thats the maximum he could get as thread on bolts was at maximum, and he had 25 mm and 20 mm width of spacers in the back bolts....and 11 mm and 12 mm spacer width in the front bolts, he said he would not want to go any more than 25 mm worth of spacing on the rear.....so to get 4 or 5 degree would be not possible with a standard setup...so whats the thoughts on this, as i only got 1.35 positive caster is this enough.....also camber i got is negative 0.30 on both sides.....thanks


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## 05GTO (Oct 6, 2004)

According to my shop manual for 66 (should be the same as 67) you should have a caster of -1 1/2 +/- 1/2 degrees. The camber should be set to +1/4 +/- 1/2 degree. The left camber should be set 1/4 degree greater than the right camber to correct for the road crown.


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## BearGFR (Aug 25, 2008)

Don't worry so much about numbers as long as they're not out by a mile... the real question is how does it drive and handle? If it feels stable, doesn't pull to one side, and doesn't feel "darty/twitchy" like it doesn't really want to go straight - it's good. Secondary to that is to monitor tire wear to make sure they aren't wearing "funny".

Bear


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## geeteeohguy (Feb 2, 2008)

4 or 5 degrees is excessive....1.35 might be too. If it doesn't jar you thru the steering column when you hit bumps, you're ok. Too much caster can cause harsh road feel thru the steering wheel. Like these guys said, if it drives fine and doesn't eat tires, you're ok.


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## fiesta62 (Jan 12, 2011)

ok thanks for the thoughts....car seems to track straight and feels fine.....the wheel align guy seemed very happy to get the figures identical both sides and the camber at negative 0.30.....i am a little concearned why its such a large stack of shims on the rear bolts....its got a good inch on the rear bolts...and about half inch on the front bolts....anyway i guess as you guys said if it all feels right then i probably is....now just got to sort out this tight steering box.....thanks


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## Eric Animal (Oct 28, 2007)

Fiesta, :agree:agree:agreethese cars are old...the large/small stack issue is/could be caused by several things....worn bushings, spring height, chassis slightly "off square", etc.....aligned is GOOD.....I wouldn't go with anymore positive caster than you already have...if the camber, and toe is correct...you'll be fine!!!!...........:cheers Eric


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## fiesta62 (Jan 12, 2011)

hello eric....ok i'm feeling better that large stack off shims in rear had me concerned but all have told me its ok....i had ball joints replaced got taller ones fitted to the top, did all bushings....did wheel bearings....so it should be all nice and tight now......camber - 0.30 toe in 2mm and caster + 1.35 .....thanks


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## geeteeohguy (Feb 2, 2008)

The shim stack is because your caster is _WAY_ positive over stock specs. The added rear shims pull the upper ball joint further back, increasing caster. If you align it to specs (negative caster) you won't need all those shims. Since you want a lot of caster, you'll have to deal with the asthetics of a big shim pack behind the A arm shafts.


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## pontiac (Mar 6, 2011)

Actually with the tall ball joints you have changed the alignment from stock, so stock specs will not apply. 
likewise if indeed you changed upper A arm bushings, then the kit you would have purchased comes with an offset shaft. Can't buy the old kit anymore with a non offset shaft. The offset shaft is provided to reduce the amount of shims for alignment because it is known that the frame over time has settled and the original straight shaft will not allow the factory specs to be achieved. that said, I have seen where the mechanic has the offset shaft installed wrong, 180 degrees, so it would take more shims than necessary. (did it myself and never changed it) so what shaft do you have and accordingly are the shims too many if the shaft was rotated on its axis. this can be easily seen from under the hood looking at the shims. let's see it. post a photo here.


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## fiesta62 (Jan 12, 2011)

pontiac...ok i have attached 2 pics of shaft, different angles both pics passenger side, i replaced all bushes got them from summit, i did not see any kit with offset arms, i just got the bushes, and taller top ball joints, lower standard ball joints, i pasted the ball joint ad below...thanks

Proforged tall ball joints may be the perfect solution to ridding your ride of negative camber curve issues. Tall ball joints are a hot trend in the aftermarket, and for very good reason. They're designed to correct fundamental deficiencies in the original suspension that causes poor handling. These ball joints from Proforged are designed to increase the effective spindle height, which in turn reverses the camber curve for significant improvement in your vehicle's overall handling. Proforged tall ball joints are built to be stronger than OEM and to help keep tires flat on the pavement for better traction, handling, and cornering.


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## geeteeohguy (Feb 2, 2008)

Pontiac is right, stock specs don't apply. Those are regular, non-offst shafts, which are fine. You could get by with less shims if you installed the off set shafts and flipped them around, but I wouldn't. That is a LOT of shims...more than I would be comfortable running. There is a lot of leverage on that back bolt.....I would be tempted to machine a block of steel and drill two holes in it and make it wedge shaped so that you could install it, and then fine tune it with just a few shims. You could measure your shim pack thickness now and get it pretty close. It would be a lot stronger/sturdier. Fancy cornering ablility is no good when you're in the ditch with a busted A arm!!!


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## fiesta62 (Jan 12, 2011)

geeteeohguy said:


> Pontiac is right, stock specs don't apply. Those are regular, non-offst shafts, which are fine. You could get by with less shims if you installed the off set shafts and flipped them around, but I wouldn't. That is a LOT of shims...more than I would be comfortable running. There is a lot of leverage on that back bolt.....I would be tempted to machine a block of steel and drill two holes in it and make it wedge shaped so that you could install it, and then fine tune it with just a few shims. You could measure your shim pack thickness now and get it pretty close. It would be a lot stronger/sturdier. Fancy cornering ablility is no good when you're in the ditch with a busted A arm!!!


aww gt now you got me worried !...my mechanic friend here also feels its way too many shims...but he didnt mention saftey concerns...just that its very unusuall to see that many he feels something is not right....but the wheel align guy is highly recommended old school....and i seen the figures on the machine it was 1.35 positve no doubt....so it is what it is....i could lessen the positive caster to have less shims but everyone seems to say positive caster is best...anyway for now i will leave it but i'm still learning what i can about it....thanks


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