Dartsun
Mopar Dude
Hello looking for some more suspension mods for my 65 Dart GT 273 904. As of now I have PST manual gear box 1.03 TB, bilstein shocks, LCA boxed in, Afco leaf springs, Addco sway bar front and rear. Thanks Dustin
Suspension upgrades for my 65 Dart
- Thread starter Dartsun
- Start date
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C Body tie rods and solid sleeves.
What are you wanting to do? Auto-X, drag race, street car? What brakes do you have?
Exactly, what is the intended use for the car?
It sounds like you already have a good start with the 1.03" bars, a good set of shocks, boxed LCA's and sway bars.
The next things I would look at are:
- Wheel alignment, make sure it isn't set to the factory numbers. You should be looking at something like -.5° camber, +3° (or more) caster, 1/16" toe in
- Brakes- if you're still running drums up front, time to upgrade. If you've already done disks, you can investigate going larger, but that will depend on wheel diameter too. You can go up to 11.75" with 15" wheels.
- Tires- if you're still running 14's or 15's with BFG T/A's, you're leaving a lot of grip on the table. 17" or 18" wheels with modern tread and rubber compounds will dramatically improve handling if you're not hung up on the classic look. And again that depends on the use of the car, for a street car it's not as big a deal, but for more serious handling it's a must
- Upper control arm bushings or tubular UCA's- With manual steering you may not want to go crazy with positive caster, but the more you run (up to about +6.5°) the more stable your handling will be. With offset UCA bushings most folks can normally get up to about 3.5° of caster, more than that will take tubular UCA's which should get you close to +5°. More than that and you'll need adjustable UCA's, like the SPC pieces sold by BergmanAutocraft. But again, with manual steering you may not want to go with that much, it increases steering effort too.
- Chassis stiffening- if you don't already have subframe connectors and torque boxes, that would be a good place to start. Obviously there's more, lower radiator supports, shock tower reinforcement etc, but you may not want/need all that for a street car.
- Solid tie rod sleeves- they'll help, they're easy to install. You don't need the larger diameter C-body ends (11/16"), the slop in the tie rods comes from the original split sleeve design. Go with solid tube sleeves and the factory 9/16" ends and you're fine, the larger tie rod ends just get in the way of tire clearance and aren't the weak link anyway
- Adjustable strut rods- these depend on your LCA bushings, if you have stock rubber LCA bushings you probably don't NEED them. If you have poly or Delrin LCA bushings I would strongly suggest going to adjustable strut rods. They let you fine tune the strut rod length, which will eliminate any binding in the LCA travel. The factory strut rods were just kind of a "one size fits all" deal, and at least from my experience they were mostly just "close enough". Not terrible, but not ideal either. It's a minor point if you have rubber LCA bushings still, but it may still be an improvement
Dartsun
Mopar Dude
Thanks for the replies. I have Kelsey Hayes discs on front with 14” BFG tires, rubber LCA bushings. Mostly my car is used for country driving back roads and a back up daily driver. Looks like my next investment be leaning towards frame connectors, torque boxes and solid sleeve tie rod sleeves.
Hard to go wrong with those improvements. All of these cars can benefit from some chassis stiffening.
Is your alignment set to match the SKOSH chart? Because if it's been set to factory specs with those radials it will feel squirrely, the factory specs are for bias ply's. The caster numbers in the SKOSH are a little conservative, just shoot for as much as you can get for + caster. With factory UCA's and bushings it won't be much, and even with manual steering you won't have any issues running +3.5° if you can get it.
Honestly, I think your biggest gain would be with rims and tires. at least go 16s or 17s, with some modern rubber compounds.
16’s are a waste of time, there’s fewer relevant tire options in 16” than 15” and possibly even 14”. Even the selection at 17” isn’t what it was just a few years ago, although it’s still much better than 14 or 15”.
I don’t disagree, there’s really no good street tire options in 14”. Pretty much just BFG T/A's and Cooper Cobra's- treadwear is 400 or higher, temp and traction ratings aren't great. They're just all season tires. But given the use of the car going 17's may not be in the cards, and may not be the "look" the OP wants. Plus it sounds like the car is SBP too, so that will really limit the wheel upgrades. And switching the whole car over to BBP for a new set of wheels gets expensive fast.
The chassis stiffening will still help, and the platform with 1.03's and sway bars will do better than anything factory even with the current tires. It will be traction limited, but that's ok. I still think I'd do the chassis stiffening first, and if better handling is still on the table after that then a BBP upgrade may be the next step with a better wheel package.
So what rim size has the most options for performance tires currently? 18? 19? 20+?
Dartsun
Mopar Dude
Yep I’m running sbp and plan to keep it that way for a while. Thanks for help everyone.
Currently? Probably 19's and 20's if you factor in what will actually fit for tire height on these cars.
It really depends on the size though. If you stay in the 245 wide range there's quite a few options in 17" and 18". Like if you look at a 245/45/17 on TireRack there's 59 tires in the "performance" category and 91 overall. If you look at a 275 though all you get for tires that are about the right height is a 275/40/17, which isn't that tall (25.6"), and there's only 33 total available and 24 in the "performance" category. A 275/45/17 would be great, but no one makes them. A 285/40/17? There's 2. 295's? Nope. 18's go the same way, if you look at a 245/40/18 there's 148 tires and 103 in the performance category. Go to 275/35/18 and there's 63 and 53 in performance, go to 295/35/18 and there's 11. Yeah, 11. Not a lot of selection, and it drops off worse as you go wider from there. In 19's at 295/30/19 there's 34 tires.
So it depends on what you're doing, I just know that running staggered 275/35/18's and 295/35/18's I'm down to 2 tire choices at TireRack. Now TireRack doesn't show every tire on the market, but you get a pretty good idea. My next time around I may try to run square at 285/35/18, gets me back up to like 20 something choices.
Nothing wrong with that! The chassis stiffening will still help. And yeah, not many of us have unlimited budgets to do everything at once so doing the chassis work now will give you a great platform to keep building from in the future. Or not, if you're happy with the results!
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