My best advice is to pull the rear end right outta there , insert your mounted wheel tires assemblies into the tub and center/square them up. Then measure between the mounting faces of the wheels and get your diff narrowed as required.
It is better to be a half inch too narrow than a half inch too wide.
Tuck them as tight to the frame as you can, leaving a minimum .25 on the inboard sides to the nearest obstruction,which at lowered height, after the front curve in the tub is stretched away, will be the shock-crossmember. Forget trying to pound that away, it don't budge much.
On the outboard side is the stiffner step in the inner tub up by the top of the quarter lip. It's about 1.5 to 2 inches higher than the lip. Your 275 on a 10 should clear it, but you never know. A 295 on the 10 won't. But you only need about an inch vertical clearance and then it is no longer an issue. .... it just depends on how low you wanna go.
I know you didn't ask, but you're the first guy I ever heard of who liked his Duster low. Not sure what the Dragstrip starter box is gonna do with that, and the 2" lowering blocks, and the driveshaft sliding back as the springs torque up.
If you lower the front a like amount with the T-bar adjusters, yur going to get into toe changes with camber changes, as the hood goes up and down. And that makes the car steer funny. If this is to be a DD or yur gonna put a lotta street miles use on her, you may end up chasing the car from one side of the lane to the other, on anything but flat and smooth roads. And it won't matter what you set the toe to, it's just gonna have a mind of it's own.
I'm just saying there is a too-low place you may not want to be in; this ain't no 64 Impala.
Sigh. Usually your information is so much better than this.
There are plenty of guys that like their Dusters low. More than a couple right here on FABO. Myself included. Maybe not so much in the drag race crowd, but that's not the point.
As for the front end right height and camber changes, I can't even believe you said that stuff. These cars have better camber curves for radials when they're lowered than when they're at stock height. Even if they didn't, it's not like you can do much about it. The control arms move in an arc, that's just the way it works. So no matter what your ride height is the camber and toe are going to change "as the hood goes up and down". There is literally NOTHING you can do about that, no matter how you set the alignment at ride height it's gonna change as the suspension travels. The static ride height just determines the starting point along the arc the suspension is going to move in. And like I said, the camber and toe curves are actually better for radial tires when the car is lowered. The suspension geometry at stock ride height was for bias ply's, and they have totally different camber needs than radials.
Sure, drag racing is a little different than a handling set up. But the stuff you're talking about- bump steer, camber curves, etc, are IMPROVED by lowering the front of the car and setting the alignment at that lower height. So that bit about lowered cars and bump steer, changing lanes on anything other than smooth roads etc is just total BS. My car is lowered, it doesn't have those problems. Hell YOUR car is lower than stock AJ, does it have those issues?
Yeah, you can go too low. But by the time you get too low for the suspension the headers won't clear a basic speed bump anyway.
His biggest issue with lowering the car isn't going to be the camber and toe, it will be the torsion bars he's going to want to run for drag racing causing the suspension to bottom out at that lowered height. If you want to run lowered in the front and not bottom the suspension you need larger than stock torsion bars. The lower you go the bigger the bars will have to be. And that's not the set up you'll want to maximize your drag race performance.
Thank you so much for that detailed response. Frankly, its gonna be a street race car, a couple of blocks from the "spot", to the "SPOT" lol will be the majority of her driving on the street. Everything else will be at the track.
As far as the lowering blocks go, they arent mandatory, im just not afraid to use a 1/2" or 1" to get the desired ride height, or as the young bucks call it, stance....
Such good info on the problem spots in the wheelwell. Currently, i only have a 15x10, and a 29.5x10.5 for mock up. So i guess if it sits and fits on that, everything should be good.
As far as the front end setup goes, im picking the brain of a local shop who builds Stock, Super Stock, and Hemi Shootout cars. Plenty of little things to do that will help us go straight while sitting low. Here is a shot of the desired ride height, and a shot of a current day Hemi Dart. Low, and with all "stock" front end goodies.
View attachment 1715439960View attachment 1715439964
A 29.5x10.5" isn't going to work in stock wheel wheels, not if the car is lowered. That's a super tall and wide tire. Even perfectly centered front to back it's going to be hard to lower the car significantly over that tire because of how tapered the wheel well is. The width is going to be an issue too. The 295/35/18's I have on my Duster are about 11.9" on the section width and about 11" on the tread width, and only 26.1" tall. A 29.5x10.5" actually has a section of 13.2", which is wider than a Duster's wheel house measurement from inner wall to quarter lip. My car has almost a full 1/2" trimmed from the quarter lip and my measurement is almost exactly 13.2"
after the cutting. Which means once you factor in tire clearance about the widest section you can have is a 12.2". On my car with the 295's and lowered the bump on the outer wheel house is the limit too, not the lip. And I'm pretty much right up on it, my car rubbed before I added the 7/8" diameter rear sway bar. And that's with a 1/2" spring offset too like I mentioned before. I don't think a test fit with a 29.5x10.5 is gonna work at all, even on a car that isn't lowered.
