Build Thread '83 T-top Coupe - Welding Holes in My Rear
- Thread starter Davedacarpainter
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I am.I thought you where going to narrow the cradle
I’m not going to shorten the half shafts and control arms to give a better looking backspacing though.
I have no idea how I would do that. I would have to pay for custom halfshafts and somehow make my own control arms. Too much for my pea brain.
- Mar 2, 2015
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No need to remake the wheel Dave.
Just move the mounting points in. As they move in the geometry changes. It changes the roll center. Someone here can probably give the dimensions and how it would be affected.
The spindles are regular old bolt in hub bearing assemblies. I'm sure there may be a axle that's shorter in one of the many front wheel drive models. Most axle cups and tripods are interchangeable. The biggest issue will be finding one with the same diameter center shaft.
The tripods are usually held on with splines and a c clip. Remove the boots, cups, and tripod bearrings. What you're left with is a shaft with splined ends.
Just move the mounting points in. As they move in the geometry changes. It changes the roll center. Someone here can probably give the dimensions and how it would be affected.
The spindles are regular old bolt in hub bearing assemblies. I'm sure there may be a axle that's shorter in one of the many front wheel drive models. Most axle cups and tripods are interchangeable. The biggest issue will be finding one with the same diameter center shaft.
The tripods are usually held on with splines and a c clip. Remove the boots, cups, and tripod bearrings. What you're left with is a shaft with splined ends.
I think I would want to make a set of control arms just to have tubular ones.
Wouldn’t chrome moly tubing work?
Can't you just find a 17x8" wheel in the proper offset to give you a nice flush rear look, and then send the wheels off to weldcraft to add 2" to the inside lip? They could even machine the hub to tuck the wheels in closer to the fenderlip if they stick out too far.
Seems like that would be easier work than modifying the IRS to fit a specific set of wheels. It might be $500ish, but how much $$$ are you talking when we start getting into modified control arms or halfshafts and such?
Do you have a wheel chosen that you want to run?
Seems like that would be easier work than modifying the IRS to fit a specific set of wheels. It might be $500ish, but how much $$$ are you talking when we start getting into modified control arms or halfshafts and such?
Do you have a wheel chosen that you want to run?
All of this talk right now about shortened half shafts and control arm is just speculation right now to see if I could do it and have the irs completely functional.
I haven’t considered the wheels yet. Still kind of like the billet specialties street lites.
I hadn’t considered taking a wheel and having it widened yet though, good idea Mike.
Hey Chris @FastDriver ,you’re one of those super smart engineer guys.
Let’s say I could shorten (or find shorter than stock) the half shafts about 2”. Then I make a new set of control arms to bring it all together. What might be a problem with geometry changes?
Let’s say I could shorten (or find shorter than stock) the half shafts about 2”. Then I make a new set of control arms to bring it all together. What might be a problem with geometry changes?
Dave,
You are seriously floating out into outerspace on this IRS stuff. With a hard tail mount you should be able to easily run 10"/10.5 wide wheels. @hoyster Have you done any measurements to confirm wheel width on a hard tail IRS? Unless you narrow the entire IRS (cradle, control arms, axles, tie rods, sway bar) and hope you still have good geometry and then you'll be able to go wider. Problem is is there a wheel that now fits your wheel specs req'd to fit your new rear end? Are they going to be custom made wheels at $800+ each? High BS/offset wheels are not common and when you do find them they're typically not great looking or do not have a front wheel in the correct offset to match the back.
Also think about this, if you want the car to hand well in turns then your going the wrong direction with the rear end. Even if you somehow find a way under $3k to narrow the rear end and have decent suspension geometry, you now have a huge tire out back and a narrow tire up front. Now you have supreme grip out back but less grip up front. It's going to make for a sketchy unbalanced car in the turns. You'll also have no replacement parts if you break or damage any of your "1 off" IRS parts so plan on making 2 of everything!
You are seriously floating out into outerspace on this IRS stuff. With a hard tail mount you should be able to easily run 10"/10.5 wide wheels. @hoyster Have you done any measurements to confirm wheel width on a hard tail IRS? Unless you narrow the entire IRS (cradle, control arms, axles, tie rods, sway bar) and hope you still have good geometry and then you'll be able to go wider. Problem is is there a wheel that now fits your wheel specs req'd to fit your new rear end? Are they going to be custom made wheels at $800+ each? High BS/offset wheels are not common and when you do find them they're typically not great looking or do not have a front wheel in the correct offset to match the back.
Also think about this, if you want the car to hand well in turns then your going the wrong direction with the rear end. Even if you somehow find a way under $3k to narrow the rear end and have decent suspension geometry, you now have a huge tire out back and a narrow tire up front. Now you have supreme grip out back but less grip up front. It's going to make for a sketchy unbalanced car in the turns. You'll also have no replacement parts if you break or damage any of your "1 off" IRS parts so plan on making 2 of everything!
I’m floating just a bit, not too much. I have a tether attached to reality.
Since you're shortening the radius of travel I'd foresee a slightly faster rate of change plus overall increase in camber and toe in angle when suspension cycles.
Also means any suspension parts out back like spring/shocks will not be tailored for the shortened radius at all. No more matched front and rear spring sets.
I feel like with a little bit of teamwork we can figure this out.
Anyone have one of these tools?
Where does the face of the IRS hub sit in relation to an SN95 94-98 disk brake rear in a fox? Or the fox drum rear? How much wider are we talking?
Take that difference, find a spacer, and bolt on the above tool with your choice of tire (295? 305? 315?) and then adjust until it fits. You'll get your answer on necessary BS and offset needed.
EDIT: nevermind, Scott beat us to it.
https://www.stangnet.com/mustang-forums/threads/89-foxbody-w-03-irs-wheel-fitment.874473/
Anyone have one of these tools?
Where does the face of the IRS hub sit in relation to an SN95 94-98 disk brake rear in a fox? Or the fox drum rear? How much wider are we talking?
Take that difference, find a spacer, and bolt on the above tool with your choice of tire (295? 305? 315?) and then adjust until it fits. You'll get your answer on necessary BS and offset needed.
EDIT: nevermind, Scott beat us to it.
https://www.stangnet.com/mustang-forums/threads/89-foxbody-w-03-irs-wheel-fitment.874473/
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That's true too. Most aftermarket manufacturers make kits assuming you'll widen your wheel base, not shorten it. On another thought, moving the shock inward two inches will shorten travel of the shock. Moving the shock location inward, closer to the pivot point (where control arms attach to subframe), is not optimal. It will greatly increase load on to the inner control arm bushings. I'm too busy to model this in Inventor for better clarity but in short, nothing good happens when moving the shock inward toward the pivot points of your control arms on an IRS rearend.
I'll do it this week Dave. As for the Rack I just did that in mine as well and it's not a hard swap but you will need the MM Hybrid shaft and I used 92 Taurus outer tie rods. I got a Cardone 22-2000 rack from Advance Auto parts for around $160 and it's great.
Is there any pictures of a car in this thread yet? Is it painted yet? I can never keep up with this progress thread.
I keep it in hiding.
Money has been the problem. Shortly after i got the car work slowed down badly for me. I made 20k less last year than i did any of the previous 13 years. That's the money that builds cars.
Work has gotten a little better in the past three or four months, while not what it used to be, it's enough to start doing some things, like the IRS. I'll also be ordering the new floor pan this week, and right front subframe rail, sfc's, etc.....
In June I will take the car out of storage and bring it home to the garage and begin working on the body finally.
It's not fast enough for me either, what can I do?
Plus I got the new truck so having this as a dd isn't as important time wise. I'll take my time with each thing and make it as nice as i can.
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