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BS on changing tire alignment specs from stock.

gtxrt

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My opinion for entertainment purposes only. My 67 RT with manual steering even if it had power steering. if you bought a new RT or GTX back in 1967 the car would handle better than most mid size cars back then. just think if they had radial tires and gas shocks handling would be a great deal better. fast forward today a lot of talk about changing alignment specs for better handling and changing parts and adding things for better handling but hurting the ride of the car and harder to steer with negative camber or positive caster. just putting my RT back to close to stock specs like camber from negative camber to near 0 camber the car rides a lot better not hitting the bumps as hard still handles very nice. I like my classic cars for the characteristics of what they were when I first started driving them. yes put on the radial tires and gas shocks but anything more If I want modern handling better gas mileage better brakes better AC more comfortable I will just hop in my new challenger.
 
My opinion for entertainment purposes only. My 67 RT with manual steering even if it had power steering. if you bought a new RT or GTX back in 1967 the car would handle better than most mid size cars back then. just think if they had radial tires and gas shocks handling would be a great deal better. fast forward today a lot of talk about changing alignment specs for better handling and changing parts and adding things for better handling but hurting the ride of the car and harder to steer with negative camber or positive caster. just putting my RT back to close to stock specs like camber from negative camber to near 0 camber the car rides a lot better not hitting the bumps as hard still handles very nice. I like my classic cars for the characteristics of what they were when I first started driving them. yes put on the radial tires and gas shocks but anything more If I want modern handling better gas mileage better brakes better AC more comfortable I will just hop in my new challenger.
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Do what you want but the car will react better with alignment settings different than stock. It will be safer for you and everyone around you too.
 
Do what you want but the car will react better with alignment settings different than stock. It will be safer for you and everyone around you too.
it handles very nicely now way better then new with wider radials and gas shocks. can't get that caster with manual steering will steer too hard anyways. am close with the camber and toe in like your chart.
 
That isn't my chart. I go waaaaay beyond it with my cars.
Manual steering is too dang slow for me. I have power steering in everything and run 8 degrees of caster in this:

000 E.JPG


Again, you're free to do what you want but in an emergency situation, cars with modern alignment settings will react faster than a manual steering car with stock settings. My cars react like newer cars yet still look like classics.
 
My opinion for entertainment purposes only. My 67 RT with manual steering even if it had power steering. if you bought a new RT or GTX back in 1967 the car would handle better than most mid size cars back then. just think if they had radial tires and gas shocks handling would be a great deal better. fast forward today a lot of talk about changing alignment specs for better handling and changing parts and adding things for better handling but hurting the ride of the car and harder to steer with negative camber or positive caster. just putting my RT back to close to stock specs like camber from negative camber to near 0 camber the car rides a lot better not hitting the bumps as hard still handles very nice. I like my classic cars for the characteristics of what they were when I first started driving them. yes put on the radial tires and gas shocks but anything more If I want modern handling better gas mileage better brakes better AC more comfortable I will just hop in my new challenger.
it handles very nicely now way better then new with wider radials and gas shocks. can't get that caster with manual steering will steer too hard anyways. am close with the camber and toe in like your chart.
I replaced the 5" wheels on my 66 Belvedere with 7 x 15's and threw on 235/75's mainly because I had them. Yeah, it was better but then I lowered the car a good inch or so and changed my alignment to as much camber and caster I could get and adjusted the toe after. It drove even better!!! I also lightened my car which enabled it to handle even better. If your car is nose heavy, yeah, it's going to be harder to steer and even worse if it has AC. Mine was factory AC but it was also a /6 with auto. It was hard to steer when I bought it in stock form though. The radials helped the steering too but getting some weight off also helped imo.
 
I really can’t remember what mine felt like in ‘68! Feels good at stock setting now though.
 
I'm in the middle of this right now.
With "new" OE type upper control arms and standard bushings, I was only getting 1 degree positive caster and 1 to 2 degrees negative camber.
Any more positive caster and the camber went more negative for street use per the chart.
I'm installing the 4 off set bushing and will report how that works out in the settings.
Won't be driving it for a while though.
1969 RR. Manual steering. 215 r70 on cop rims.
I've driven A bodies for years with manual steering and those same wheels.
 
Back in the 70's I bolted on a set of Michelin radials on my 67 GTX, manual steering. No other changes, what a great upgrade and I didn't die! Changed my 70 Challenger R/T over to radial T/As in the 70's as well with no other changes, I didn't die then either.
 
Back in the 70's I bolted on a set of Michelin radials on my 67 GTX, manual steering. No other changes, what a great upgrade and I didn't die! Changed my 70 Challenger R/T over to radial T/As in the 70's as well with no other changes, I didn't die then either.
No one ever said you would die... However if your already having an alignment done changing from 1970 numbers to 1990's numbers costs you zero dollars but makes for a much better driving experience... Not having to make constant minor course corrections when going down a straight highway at 75 MPH is kinda nice, having some feedback as you turn into a corner rather than a numb vague feel s also kinda good... Being able to take a turn at higher speed without squealing tires = good...
But hey, you do you & I'll do me.....
 
No one ever said you would die... However if your already having an alignment done changing from 1970 numbers to 1990's numbers costs you zero dollars but makes for a much better driving experience... Not having to make constant minor course corrections when going down a straight highway at 75 MPH is kinda nice, having some feedback as you turn into a corner rather than a numb vague feel s also kinda good... Being able to take a turn at higher speed without squealing tires = good...
But hey, you do you & I'll do me.....
mine was done with a laser so the specs should be what they say they are. mine handles very nice no numb feeling to speak of and I can take my hands off the wheel for 5 seconds at least. the tires were 1.3 negative camber before and were jarring over the bumps.
 
I aligned my GTX a couple weeks ago and set camber at .25 degrees (-). Caster came out at 1.87 degrees (R) and 1.75 degrees left. I set toe in at 1/8 in with some new alignment plates that measure distance a couple inches past the tire edge. I’m used to using an old tram gage that snugs in closer to the tire so I’m thinking the 1/8” on the plates would be something less on a tram gauge. It’s not as much caster as I would like with PS but it tracks straight an steering return is fine.
 
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I imagine you set your timing at 7-8deg advanced and your carb a bit on the rich side as well.
I set my timing at total timing. I set my carb and tune with my spark plugs and seat of the pants and a g-tech meter. I build my engines to get as much power without effecting drivability you will never really know it is not stock till you get on it. the right mild cam, light weight thin ring pistons and many other things that make power without bad side effects. my Newport 440 weighs 4400 lbs runs low 14's goes sideways off the line with only 2.94 sure grip. a lot of negative camber hurts ride and too much + caster for manual steering is harder to steer in my mind that is going backwards over stock.
 
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No one ever said you would die... However if your already having an alignment done changing from 1970 numbers to 1990's numbers costs you zero dollars but makes for a much better driving experience... Not having to make constant minor course corrections when going down a straight highway at 75 MPH is kinda nice, having some feedback as you turn into a corner rather than a numb vague feel s also kinda good... Being able to take a turn at higher speed without squealing tires = good...
But hey, you do you & I'll do me.....
I posted previously a quote here from a recent "Racecar Engineering" magazine and it commented on the handling negatives of too much caster. We are not talking about harder steering nor the benefits straight line consistency. The article was taking about how caster effects corner weights and load transfer on the chassis when turning. I am definitely of the school too much caster has a downside, for handling. They even referred to unsuspended go karts to illustrate chassis jacking from caster. What amount of caster is too much, I suspect is very subjective.
I may not condone the OP's solution, but I can't broadly say his thinking is wrong
 
like I first said just my opinion not telling anyone what to do or what's right for them. I was saying what is right for me and if I want a modern ride I will drive my 2023 challenger.
 
My PS cars I always get as much caster as I can with the offset bushings. MS though I can understand fitting into the stock caster settings to help a bit with parking and low speed jockeying. With the stock settings and the frontend in good shape I never encountered wandering or rut following with radial tires and stock offset wheels, I don't generally limit speeds to 75MPH either. My "modern" car is more uncomfortable to drive on rutted pavement than any of my old ones, which is understandable with the wide tires, wheel offset and settings, this thing requires a death grip on the wheel.
No BS, in a 700 mile day, imperfect pavement, 70-80MPH all day long, I'd take the GTX (with the stock wheel offset and radials not the catch a rut Polyglas in this photo) over my Viper. My shoulders and forearms would know the difference in 15 minutes.

viper9.JPG


oldmopar5.jpg
 
I posted previously a quote here from a recent "Racecar Engineering" magazine and it commented on the handling negatives of too much caster. We are not talking about harder steering nor the benefits straight line consistency. The article was taking about how caster effects corner weights and load transfer on the chassis when turning. I am definitely of the school too much caster has a downside, for handling. They even referred to unsuspended go karts to illustrate chassis jacking from caster. What amount of caster is too much, I suspect is very subjective.
I may not condone the OP's solution, but I can't broadly say his thinking is wrong
Exactly. As far as I know, about the only thing that caster will do for you is straight line stability (take your hands off the wheel and the car tracks straight down the road) Because of Chryslers "loosie goosey" power steering, some think that a lot of extra positive caster is needed to make up for the power steering. Not really. Correct the over zealous power steering pressure and a degree or so of caster is all that's really needed.
 
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