64 Dart Suspension Upgrades

[RustyRatRod]

the Green Brick 69 Valiant out performed many high dollar sports cars in the one lap of America race with some well thought out simple upgrades

Exactly. @autoxcuda is a great member here who will share some info too. He has a badass little cuda.

 

[chinze57]

I understand. A lot of guys either have forgotten or just don't know that the Valiants of 1960 won a then new compact car NASCAR series. They didn't just win. They placed in the first seven spots. All of that was done with stock or near stock suspensions, because they didn't have all the fancy stuff we have today. So be careful shopping around at what's called an "upgrade".

Learning that the cars absolutely crushed the competition, I don’t see why I would need to mod the engine. It’s a solid engine, capable of putting out plenty of power.

Currently my car feels mostly fine as far as the engine goes. I have issues with it stalling on me at a stoplight that I’m trying to figure out, but by and large it’s great. The suspension is so... squishy I guess. There’s lots of body roll, and yet i can feel every bump in the road. I hope to get rid of some of the harshness, reduce the body roll, and just make it all around better in that sense.

I believe the current steering is 24:1. I do have lots of trouble with it when stationary so I’m not sure I’d do 16:1, just don’t think it’s really necessary on a daily driver. I have lots of play (90° in one direction, normal play in the other) in the steering I’m hoping to eliminate that with a coupler rebuild and alignment.

 

[RustyRatRod]

Boy, that 16:1 box sure is tough if you're not rolling. I'm a big guy too with a lot of upper body strength and I didn't like it. Even as light as the A bodies are, it's tough to turn that thing.

 

[chinze57]

Boy, that 16:1 box sure is tough if you're not rolling. I'm a big guy too with a lot of upper body strength and I didn't like it. Even as light as the A bodies are, it's tough to turn that thing.

I’m in good shape and the 24:1 is... an inconvenience at worst. Under average conditions, it’s no big deal trying to make a turn from stationary, but having to turn the wheels all the way to one direction can Be difficult and tiring If I’m trying to fit into a tight spot, I can’t imagine putting a 16:1 on the car

 

[72bluNblu]

the Green Brick 69 Valiant out performed many high dollar sports cars in the one lap of America race with some well thought out simple upgrades

While that is true, and I wholeheartedly endorse most of the upgrades on the GreenBrick's build, keep in mind that the GreenBrick was built in 1992. For those keeping track that's now 28 years ago. While it was a great recipe at the time, there has been a significant improvement in the parts available, the tire compounds available, and the handling capabilities of "the competition". A lot of what was done on the 'brick was done because that's all that was available at the time, and there has been a MASSIVE improvement in aftermarket support for handling mopars. In 1992 there was almost nothing for aftermarket support if you wanted to make your Mopar handle well.

I'm not saying that the modifications used by the GreenBrick don't work, they do. But using modern tires now is very different from using modern tires in 1992. And with some of the aftermarket handling parts now available it's pretty easy to surpass the capabilities of the greenbrick. Honestly, with the parts you can get from Hotchkis, QA1, BergmanAutocraft, FirmFeel and PST and the modern tires now available you can easily surpass the level of handling that the greenbrick had.

For example, a set of tubular UCA's can dramatically improve on the alignment settings run by the GB. I wouldn't even bother with poly strut rod bushings, because while they improve the fore/aft shift of the LCA they also stiffen the up/down travel of the strut rod, which increases the potential for binding. A set of adjustable strut rods improves both and allows tuning to your specific car. A set of 18" wheels and modern tires can easily surpass the tire capabilities of the GB, and suspension performance starts at the tires (true then and now). The torsion bar diameters used were conservative, and an improvement in both tire and shock technology makes larger torsion bars easy to run and yields a big improvement in handling without a large downside in ride quality.

While it makes use of a lot of good principles, the GB is an outdated model.

Learning that the cars absolutely crushed the competition, I don’t see why I would need to mod the engine. It’s a solid engine, capable of putting out plenty of power.

Currently my car feels mostly fine as far as the engine goes. I have issues with it stalling on me at a stoplight that I’m trying to figure out, but by and large it’s great. The suspension is so... squishy I guess. There’s lots of body roll, and yet i can feel every bump in the road. I hope to get rid of some of the harshness, reduce the body roll, and just make it all around better in that sense.

I believe the current steering is 24:1. I do have lots of trouble with it when stationary so I’m not sure I’d do 16:1, just don’t think it’s really necessary on a daily driver. I have lots of play (90° in one direction, normal play in the other) in the steering I’m hoping to eliminate that with a coupler rebuild and alignment.

Your car likely feels both "squishy" and like you can feel every bump in the road because you're riding on the bump stops. That's a real issue with smaller torsion bars, they barely had enough wheel rate to keep the car from bottoming out to begin with at the stock ride height. A lot of these cars now are lower than stock, either just because of torsion bar sag that hasn't been adjusted out or directly because someone lowered the car with the torsion bar adjusters. What you get is a squishy ride with lots of body roll, but also a rough ride because the suspension is constantly bottoming out on bumps and potholes. It seems counterintuitive, but larger torsion bars can give a smoother ride than the stock ones if the suspension is worn out. The stock bars were too soft, and the bump stops were gigantic to make up for the lack of wheel rate and offset the bottoming suspension.

Your steering will likely improve a lot when you replace your suspension bushings, tie rods ends, pitman and idler arms, and rebuild the coupler. Even if all of those parts are only slightly worn it all can add up into a lot of play.

Boy, that 16:1 box sure is tough if you're not rolling. I'm a big guy too with a lot of upper body strength and I didn't like it. Even as light as the A bodies are, it's tough to turn that thing.

I run a 16:1 manual steering box with 275/35/18 front tires and 6.5° of caster. I'm 5'8" and 155 lbs, so, not really a big guy. While parallel parking my car isn't a fun activity, and the steering is pretty heavy under 15-20 mph, it's totally manageable even on a daily driver like mine. No, it's definitely not everyone's cup of tea and I get that, but it's not as bad as many think and you do get used to it. Just a little planning and making your steering inputs while you're rolling instead of trying to dry steer while at a standstill makes a big difference.

 

[C130 Chief]

Best fix is to avoid turning the wheels with the vehicle static. It's really hard on stuff. Think about it, all that extra force is applied to the entire steering linkage. Wears tires more too.

 

[RustyRatRod]

I’m in good shape and the 24:1 is... an inconvenience at worst. Under average conditions, it’s no big deal trying to make a turn from stationary, but having to turn the wheels all the way to one direction can Be difficult and tiring If I’m trying to fit into a tight spot, I can’t imagine putting a 16:1 on the car

I think the 20:1 is a good compromise. I may look into that once I start driving mine again. I'm almost there, too.

 

[chinze57]

I think the 20:1 is a good compromise. I may look into that once I start driving mine again. I'm almost there, too.

After I’ve upgraded or replaced other components to improve handlings, I may decide to go 20:1. I really like manual steering and brakes, and have no intention of making them power. A bit more effort for slighter better response seems good

 

[chinze57]

So I upgraded the suspension on my '64 Dart to handle better, and this is what I have learned.

Do:
-Replace all the bushings, ball joints, and tie rod ends.
-Upgrade torsion bars to 1" bars
-KYB gas a just shocks if your cheap
-Bilstein shocks if your not cheap
-US car tool stage 2 chassis stiffening
-MP or Espo 6leaf rear springs
-Hellwig hollow sway bars front and back
-11.25" front disks
-dual pot master cylinder

Don't
-manual steering box 16:1 ratio
So this steering box does exactly what it's supposed to and does have a nice quick ratio. However, the ratio is not friendly for quick transition and greatly increase steering effort when the car has wide modern wheels and sticky tires. I'd suggest a firm feel quick ratio power box like a borgeson.

-Do not try to slam the car in search of increased handling. I did initially and had issues with bump steer and unloading the suspension in bumpy corners. Also it's hard to keep your pinion angle right and drive shaft from hitting the floor.

As you can see from the pics. I went higher and higher with mine over time. The car became significantly more enjoyable to drive.

For a true street car, suspension travel is key.

View attachment 1715533041

View attachment 1715533043

View attachment 1715533045

Hey, I’ve got a question for you- what size was your rearend, and how do I identify mine?

I got a quote back from Espo, and they asked which size axle I have so as to send the correct U-bolts. Also- Espo works out to be much cheaper than some lower quality alternatives.

 

[Bogie]

Axle ID

 

[chinze57]

Axle ID

View attachment 1715539055

Awesome! Thank you