73' B3 340 Duster pro touring build
- Thread starter 76orangewagon
- Start date
-
76orangewagon
Well-Known Member
a68postcar
Well-Known Member
It has to be a conspiracy! Mine says the same darn thing!
76orangewagon
Well-Known Member
While waiting for my other rear suspension parts not here yet, I decided that I would tackle a what I thought would be a easy and fast project....epoxy the broken tab back on, once I removed the PLYMOUTH trim I realized that where were 7-8 hairline cracks under that as well as the previously mentioned broken tab so I got out the cut off wheel and opened up the cracks to fill them with enough epoxy that they'll hold together...once that dried, I reinforced the cracks on the underside for extra support...more to follow on this side adventure since I'll be back on the rear suspension in a day or so........ changes are in the works for the rear shock mount and the QA1 adjustable shocks are here.
mopar383
Well-Known Member
Sweet Ride ...Im over in the Streetsboro area . Cant wait to see it
Riddler
Project EH-Body
I did the same thing with my grill. I had a 73/74 grill for peices and fixed my 75/76 grill. If you need any peices let me know. I've got a whole grill. No tabs left.
Riddler
Riddler
76orangewagon
Well-Known Member
Thanks.......
76orangewagon
Well-Known Member
I've got a question to all the experienced knowledgable members who are following this build.....I recently recieved a couple post on another site that has me a little concerned regarding the rear suspension.. please take a moment or two and read the posts and see if you think there accurate. I hate to be wrong setting this suspension up and have to correct it later when I can change things pretty easily now.
1) Looks like any articulation that the rear end will see (which will only be a couple degrees) will be absorbed by the bushing twisting and deforming which is exactly what they are designed for. It will reduce the noise and still allow movement which is good if thats what you want. If you want 0 deflection and perfect alignment at all times, then use rod ends.
Looking at the mounting locations of your lower links, the rear end of that car is going to squat down FAR when you hit the gas hard
2) No that is not a good thing for weight transfer. The rear end of your car will squat a little with a well designed system because of weight transfer. With what you have set up, the rear end will squat because of weight transfer and because of poor suspension geometry. Your lower links have the axle mounts quite a bit higher than the frame side mounts. When you take accelerate the link has large amounts of compression force transferring thru it. With the front mount being lower than the axle mount, this will cause some upward force on the axle mount (pushing the axle closer to the frame of the car) and the frame mount will be also forced down. If you leave the suspension and ride height where they are, you will more than likely use up all of your suspension travel and hit the bump stops just taking off hard
You are right that other suspensions have been designed in a similar way but they are not designed to ride as low as you are planning. Do you want to avoid this problem or are the brackets set in stone and you just really want that super low ride height?
There are 3 things you can do here if you want to correct this
1) raise the front lower control arm mount. This would be a huge pain in the butt because you would have to recess it up thru the frame rail so I do not recommend this
2) Lower the rear mount. build new brackets that will put the rear mount slightly lower than the front. This one is relatively easy and what i would recommend if you want to keep your ride height
3) Raise the ride height of the car. Move the axle further away from the frame rails which will change the ride height of the car but you will have more ground clearance under it and your suspension geometry will be much better.
Looking at the mounting locations of your lower links, the rear end of that car is going to squat down FAR when you hit the gas hard
2) No that is not a good thing for weight transfer. The rear end of your car will squat a little with a well designed system because of weight transfer. With what you have set up, the rear end will squat because of weight transfer and because of poor suspension geometry. Your lower links have the axle mounts quite a bit higher than the frame side mounts. When you take accelerate the link has large amounts of compression force transferring thru it. With the front mount being lower than the axle mount, this will cause some upward force on the axle mount (pushing the axle closer to the frame of the car) and the frame mount will be also forced down. If you leave the suspension and ride height where they are, you will more than likely use up all of your suspension travel and hit the bump stops just taking off hard
You are right that other suspensions have been designed in a similar way but they are not designed to ride as low as you are planning. Do you want to avoid this problem or are the brackets set in stone and you just really want that super low ride height?
There are 3 things you can do here if you want to correct this
1) raise the front lower control arm mount. This would be a huge pain in the butt because you would have to recess it up thru the frame rail so I do not recommend this
2) Lower the rear mount. build new brackets that will put the rear mount slightly lower than the front. This one is relatively easy and what i would recommend if you want to keep your ride height
3) Raise the ride height of the car. Move the axle further away from the frame rails which will change the ride height of the car but you will have more ground clearance under it and your suspension geometry will be much better.
76orangewagon
Well-Known Member
Heres the bracket and link in question that he's refering to
when you get it figured out...clue me in...I'm still in the 70's with a 4-bar/4 link set-up. Never could figure out how these triangulated 4-bar set-up hook up....there is no instant center or imaginary intersection of the bars....I figured it must be for auto-cross and I not about to make my 70's hot rod into a foriegn race car....thats just me
I did notice ....I think it is Abody Joe...has a yellow dart(?)...when he lauches his squats like I've never seen before...and I think he has a Bill O'Reiley (AlterKation) Lynx set-up or whatever you call it
I did notice ....I think it is Abody Joe...has a yellow dart(?)...when he lauches his squats like I've never seen before...and I think he has a Bill O'Reiley (AlterKation) Lynx set-up or whatever you call it
dusterbd13
Well-Known Member
theres an online 4 link calculator that ive used a couple of times. helps you determine antisquat, roll center, etc. ill do some digging and see if i can find it again.
Michael
Michael
dusterbd13
Well-Known Member
found where i found it at. heres the link
http://protourings10.com/index.php?topic=73.0
http://protourings10.com/index.php?topic=73.0
HemiMark
Well-Known Member
Now that is pretty cool............. I need to get the tape measure out!
fstfish66
Well-Known Member
what a koool project,,first ive seen this topic ill be following along,,,,super nice work,considering swapping my 4 link to a triangulated 4 bar,,
76Orange,
I have seen cars with single leafs and four links in the back that drag and every car I have seen lifts in the front and rarely drops in the back.
Now I am no Engineer but I would think that no matter how you mount the lower control arm mount that the rear end is going to do what ever the springs and shocks let it do.
If you want a rear end that will not suck-up into the wheel well than get a stronger spring and a high quality shock to control the compression.
The way I see it everyone is going to have an opinion of what to do for your build, because they do not have to live with the decision. You have been do a great job on your build I say keep going with what you feel is right. Don't second guess your work, you may regret doing it their way later down the road.
I have seen cars with single leafs and four links in the back that drag and every car I have seen lifts in the front and rarely drops in the back.
Now I am no Engineer but I would think that no matter how you mount the lower control arm mount that the rear end is going to do what ever the springs and shocks let it do.
If you want a rear end that will not suck-up into the wheel well than get a stronger spring and a high quality shock to control the compression.
The way I see it everyone is going to have an opinion of what to do for your build, because they do not have to live with the decision. You have been do a great job on your build I say keep going with what you feel is right. Don't second guess your work, you may regret doing it their way later down the road.
76orangewagon
Well-Known Member
I forund a guy who knows this stuff inside and out, he's going to bring over his computer with a chassis program ( probally the same one that got linked in the above thread). He wont be coming over till the first week of August but he said no problem figuring this stuff out for a proper set-up...Also I bought QA1 single adjustable coilovers and 175lb springs. Thanks for the support...By the way, are you going to the Nats ?
Thanks... I will have this figured out by the time were having a cold alcoholic beverage in Columbus, can't wait to see the car!
76orangewagon
Well-Known Member
thanks for the help dusterbd13....like HemiMark, I'll be getting out my tape measure....Is it still HemiMark since the Hemi's gone???????
I am not able to go to the Nats this year. As long as work does not interfere I will be taking my car there next year though.
Work always seem to interfere with my personnel life. I wish there were better car shows here in Texas, but nothing Mopar Specific.
Work always seem to interfere with my personnel life. I wish there were better car shows here in Texas, but nothing Mopar Specific.
76orangewagon
Well-Known Member
Well since I'm waiting for the professional suspension guy to come tell me whats right and whats wrong with my set up instead of just winging it, I thought I'd get the new shock cross member made..... I liked the tube design I had mocked up but it seemed to mount the shocks too low in relation to the axle and I'd have to make brackets that would hang down below the pumpkin center....so with this design I can put the shock inside the rail and also was able to notch the ends to conform to the trunk floor once welded..lt ended up moving the shocks 1.5" higher toward the floor pan. I started with a piece of 1.5" x 3" rectangular steel with .120" wall which gave me 1.250" inside width, perfect for the bushing width of the QA1 shocks... I removed about half of the 3" width and started fabricating from there.....I still need to drill 3 holes per side which will allow me to change the shock angle if needed down the road...my plan still is to have every suspension piece build with adjustability. I also picked up my trunk from the Media blaster, again turned out to be a real nice solid piece...if you look you'll notice a dent toward the top rear, Since I plan on building a small custom steel spoiler it will end up being covered up. I also got out the hole saw and vented the rear for a drain plug.
76orangewagon
Well-Known Member
So a page or two back I asked about relocating the wiper motor to the inside of the passenger compartment and got several pics and idea's (THANKS). So today I decided that since I want a smooth look regarding the firewall I figured That the wiper notch in the firewall needed to go....... on the inside I added a extra lip just in case i need to bolt something up down the road....... sorry about the quality of the pics, forgot my camera and had to use a cell phone
a68postcar
Well-Known Member
just what i'd have done!
76orangewagon
Well-Known Member
If thats a offer to help I'll take it.........although my goal is to be done by the Nationals, I just don't know what year...
-
