12:05 Garage- ’70 Duster build

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Yes. When I was with Brian in St. Louis he measured and the front of his was lower than mine. I don't recall what size tire he has up front to know if it was lower due to tire height.
I got down pretty low, using the shorter bump stops that you included with the bar. Not achieva with stock ones..

Screenshot_20250818-160931_Gallery.jpg
 
Do you think the bottom stance is doable on stock type front suspension? Or will you run out of LCA clearance?

Running out of LCA clearance and tire clearance to the inner fender well happen pretty close to the same time. I know on my Duster the QA1 tubular LCA's add some clearance to the LCA, and I run a short bump stop on the frame horn, but, at the ride height I run max compression puts the tire up against the top of the inner fender well anyway. Stock LCA's would hit first, but depending on the height of the tire there wouldn't be much room left anyway.

Ma Mopar's solution on the T/A, AAR and Nascars looked like this, frame notched for LCA clearance

Screenshot 2023-04-19 at 5.14.55 PM.png


But with stock fender wells adding LCA travel would also require something like this, so the tires didn't hit the sheet metal at full stuff
img_0639_zpsvqasevco-copy-jpg.1716206246


This is where I sit with the QA1 LCA's and 25.7" tall front tires, and I'm out of room to the sheet metal at full compression. Fender openings are about 24 7/8" from the ground.
img_7666-jpeg.1716312612
 
Running out of LCA clearance and tire clearance to the inner fender well happen pretty close to the same time. I know on my Duster the QA1 tubular LCA's add some clearance to the LCA, and I run a short bump stop on the frame horn, but, at the ride height I run max compression puts the tire up against the top of the inner fender well anyway. Stock LCA's would hit first, but depending on the height of the tire there wouldn't be much room left anyway.

Ma Mopar's solution on the T/A, AAR and Nascars looked like this, frame notched for LCA clearance

View attachment 1716443601

But with stock fender wells adding LCA travel would also require something like this, so the tires didn't hit the sheet metal at full stuff
img_0639_zpsvqasevco-copy-jpg.1716206246


This is where I sit with the QA1 LCA's and 25.7" tall front tires, and I'm out of room to the sheet metal at full compression. Fender openings are about 24 7/8" from the ground.
img_7666-jpeg.1716312612
I don't know how the Duster fender compares to the Darter fender, but I'm sitting at 24.5" on the front. And I did go for a drive and the rear settled more than that photo. The rears were at 24". That was entirely too low and the driveshaft was practically touching the tunnel in the back. I took my lowering plates out and now the back is 24.5" also. My rear tires are taller than the front, so they will be tucked more.

I haven't run into the problem of the tire hitting the top of the wheel well. It was hitting the coil over hoop pretty goo early on, then I modified it to move it out the way. It will still touch it slightly when turned full lock in a turn, but I don't even notice, it just brushes the paint off.
 
Yes. When I was with Brian in St. Louis he measured and the front of his was lower than mine. I don't recall what size tire he has up front to know if it was lower due to tire height.
Mine, with 245/40-18x9 was lower than Tim's in the front, but higher in the back. I need to consider lowering the rear spring to the upper hole, about 1". However, I really like the way it looks right now, and with my rear swaybar tightened, I can force it into oversteer with effort. It doesn't snap. Also consider my tires size to Tim's, and his car is lighter than mine in the back.
HemiDuster 01.jpg
Autocross.jpg
HemiDuster 03.jpg
HemiDusters 4.jpg


Front: 245/40-18 to 265/40
Rear: 275/35-18 to 295/35
 
I don't know how the Duster fender compares to the Darter fender, but I'm sitting at 24.5" on the front. And I did go for a drive and the rear settled more than that photo. The rears were at 24". That was entirely too low and the driveshaft was practically touching the tunnel in the back. I took my lowering plates out and now the back is 24.5" also. My rear tires are taller than the front, so they will be tucked more.

I haven't run into the problem of the tire hitting the top of the wheel well. It was hitting the coil over hoop pretty goo early on, then I modified it to move it out the way. It will still touch it slightly when turned full lock in a turn, but I don't even notice, it just brushes the paint off.

The Duster and Dart wheel opening height in the front fender is pretty much the same, when I switched the car over to the Dart fenders that particular measurement didn't really change at all.

My fronts are 275/35/18's which come in at 25.6", rears are 295/40/18's at 27.4". The rear of my car is too high, I didn't change anything when I went from 295/35/18's to 295/40/18's so the rear openings are at like 26-1/4". I have a set of half inch blocks I should throw in there if I do anything other than street driving. But I haven't had any issue getting +6.5° of caster so there's that.

If the fronts aren't hitting the top of the inner fender at that height it would suggest you don't have as much compression travel, either because of physical limits (the suspension bottoms first) or because the suspension is stiffer and you're not bottoming it. Although my wheel rate is 300 lb/in and I can still bottom my suspension so it probably isn't that.

Compared to the stock suspension the QA1 LCA's do add almost 1" of compression travel, I run a 3/8" bump stop the old design didn't come with so I don't get quite that much. I run a taller upper bump stop, so my ride height sits roughly in the middle of the range of travel. Despite being almost 2" lower than stock (my a-b is 0) I pretty much retained the factory amount of travel, around 5.5" inches.

Adding the inner fender clearance is a winter project I have planned, after that I may consider going to the 73/74 B-body LCA's which add even more compression travel. I'd have to moderate that with a taller bump stop I would imagine, but that's not a bad thing.
 
The Duster and Dart wheel opening height in the front fender is pretty much the same, when I switched the car over to the Dart fenders that particular measurement didn't really change at all.

My fronts are 275/35/18's which come in at 25.6", rears are 295/40/18's at 27.4". The rear of my car is too high, I didn't change anything when I went from 295/35/18's to 295/40/18's so the rear openings are at like 26-1/4". I have a set of half inch blocks I should throw in there if I do anything other than street driving. But I haven't had any issue getting +6.5° of caster so there's that.

If the fronts aren't hitting the top of the inner fender at that height it would suggest you don't have as much compression travel, either because of physical limits (the suspension bottoms first) or because the suspension is stiffer and you're not bottoming it. Although my wheel rate is 300 lb/in and I can still bottom my suspension so it probably isn't that.

Compared to the stock suspension the QA1 LCA's do add almost 1" of compression travel, I run a 3/8" bump stop the old design didn't come with so I don't get quite that much. I run a taller upper bump stop, so my ride height sits roughly in the middle of the range of travel. Despite being almost 2" lower than stock (my a-b is 0) I pretty much retained the factory amount of travel, around 5.5" inches.

Adding the inner fender clearance is a winter project I have planned, after that I may consider going to the 73/74 B-body LCA's which add even more compression travel. I'd have to moderate that with a taller bump stop I would imagine, but that's not a bad thing.
Oh I can stuff the tire into the wheel well if I take the coil over off and just cycle suspension with a floor jack under the tire. The HDK has almost 6" of travel. It just isn't happening with the coil over installed and driving. The car doesn't roll enough in hard turns. Quite honestly, headers and exhaust would bottom out on the ground before stuffing a wheel that much on normal straight line driving. I'm also running a 265/35 right now which is a little shorter than your 275. I'll likely bump up to the 275 next set of tires. I chickened out when I ordered these since I heard they run big. I recently saw a picture of a 305 RE71 (my current tire) compared to a 315 Yok and the RE was significantly wider. Go figure...
 
Yes. When I was with Brian in St. Louis he measured and the front of his was lower than mine. I don't recall what size tire he has up front to know if it was lower due to tire height.

I got down pretty low, using the shorter bump stops that you included with the bar. Not achieva with stock ones..

View attachment 1716443598

Running out of LCA clearance and tire clearance to the inner fender well happen pretty close to the same time. I know on my Duster the QA1 tubular LCA's add some clearance to the LCA, and I run a short bump stop on the frame horn, but, at the ride height I run max compression puts the tire up against the top of the inner fender well anyway. Stock LCA's would hit first, but depending on the height of the tire there wouldn't be much room left anyway.

Ma Mopar's solution on the T/A, AAR and Nascars looked like this, frame notched for LCA clearance

View attachment 1716443601

But with stock fender wells adding LCA travel would also require something like this, so the tires didn't hit the sheet metal at full stuff
img_0639_zpsvqasevco-copy-jpg.1716206246


This is where I sit with the QA1 LCA's and 25.7" tall front tires, and I'm out of room to the sheet metal at full compression. Fender openings are about 24 7/8" from the ground.
img_7666-jpeg.1716312612

So yeah, based on all this I should be able to get the ride height I want with just short bump stops. I want to be able to drive on the roads around here so I'm not looking to get it super low. Thanks everyone!
 
Moparty is almost here!!!
Here's an update since my last one. I ended up taking the lowering plates on the leaf springs out. After a quick drive for the suspension to settle, it was very obvious that it was way too low. it dropped more than that last picture I shared. The rear wheel opening was 24" from the ground and that's with a 26" tall tire. The driveshaft was about 1/4-1/2" off the tunnel. Oh, I also did a small reverse mini tub to keep the tires off the "hump" in the outer wheel house. That wasn't nearly as bad as I thought it would be.
The next crazy thing was this weird whistling sound coming from the front of the engine after it got up to operating temperature. I thought it was maybe an idler bearing so I took the belt off and the noise continued. I went through listening to everything I could with a screwdriver to my ear finding nothing. As I'm standing over the engine with it running and contemplating life decisions, I squeeze the hose from my catch can to the intake and the noise stops. WTF?!? I take the catch can off to find a very small amount of oil, but it smelled very strong of gasoline. I freak out, pull all the plugs, which looked good, did a compression test, also good. Then I wonder if the PCV valve is bad. A quick internet search shows a bad PCV can result in oil smelling like gas. At this point, I don't know what to think so I get a new PCV, go for a drive and its fixed. All I can assume is the front crank seal was whistling from the faulty valve. I don't know and I don't get it. What I do know is its fixed. So weird. I changed the oil since it smelled like gas. Likely overkill, but for $50, I don't want diluted oil.
Yesterday I went to my local autocross with my typical 100 mile drive round trip. The car felt great, very confidence inspiring. I can definitely make it throttle oversteer now, which is something I could never do with the 235s up front (and t-bar suspension if I really want to ruffle some feathers). I may need to mess with some rear tire pressures or even make a micro adjustment to my front bar. (adjust one side) I finished 15th out of 73 cars, which is about 15-20 more than we normally have. I'm anxious to see the pictures from the event so I can see how the car looks when its working. I'll share them here if any of them are good. If I want to make excuses, there was a family there with a race prepped miata just off the SCCA nationals where the mom won her class for the 6th year in a row and the dad and son can drive the wheels off that thing.
If anyone is at Moparty, come check the car out. You know where to find me!
 
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Very cool! Is that like a season long event thing?
3 days of competition in autocross, drag racing, and 3S challenge, which is a standing start to around 70MPH, then turn 180 degrees and head back the other way about half that distance and stop in a box of cones without hitting any of them. It's a pretty exhausting weekend even without the 9 hour drive to get there.
 
3 days of competition in autocross, drag racing, and 3S challenge, which is a standing start to around 70MPH, then turn 180 degrees and head back the other way about half that distance and stop in a box of cones without hitting any of them. It's a pretty exhausting weekend even without the 9 hour drive to get there.
Very cool. Not familiar with it at all. Regardless, congratulations!
 
Do you have any video? I'd enjoy seeing it since I've never seen one of those competitions before. It's hard to get a sense of how quick your going in those still images.
 
Do you have any video? I'd enjoy seeing it since I've never seen one of those competitions before. It's hard to get a sense of how quick your going in those still images.

I went to a close by 410 sprint car race @ Fremont , Ohio a few years back to watch my nephew. There was a white car qualifying that was hauling ***, you could hear the difference between him and EVERYONE else. It was a young Kyle Larson.

when I attended MoParty., the second Joe hit the track, I could hear the difference between him and the rest.
 
Do you have any video? I'd enjoy seeing it since I've never seen one of those competitions before. It's hard to get a sense of how quick your going in those still images.
I didn't record many runs at Moparty, but this was one of the better runs, but not my fastest. | Talbot's Turn Fast Podcast

This isn't my fastest run. I think I only recorded 3 of them throughout the whole weekend. I just didn't feel like messing with it.

That's my podcast page, it should be public regardless if you have a FB account or not.
 
I didn't record many runs at Moparty, but this was one of the better runs, but not my fastest. | Talbot's Turn Fast Podcast

This isn't my fastest run. I think I only recorded 3 of them throughout the whole weekend. I just didn't feel like messing with it.

That's my podcast page, it should be public regardless if you have a FB account or not.
Wow, thanks for that. Really puts it into perspective for the 99.99% of us who don't autocross. That thing flat out hauls ***.
 

Wow, thanks for that. Really puts it into perspective for the 99.99% of us who don't autocross. That thing flat out hauls ***.
It’s the most fun you can ever have with your car. I love bringing people for rides who don’t know what to expect. Even my friend that has gone to Moparty with me the last 4 years seemed a little spooked the first few runs. The 3S heading straight to the wall at 70MPH really had him hitting the passenger side brake! LOL!
 
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