Billet rear hubs, rotating mass, suspension geometry, weight reduction

LSxBakakos

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May 29, 2022
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With winter becoming closer by the day, figured I'd get a nice little project to keep myself busy during the off season. I've set up numerous drag cars, road race cars etc. This is a bit of a game changer considering I've never set something up that sees the track, towing and road trips. It started off as the goals of touching 11s on sbe, full weight, boat anchors and zero weight reduction. Goals been beat, just wanna dive deeper

First up I found IMS billet rear hubs for the aam 11.5, they shave 28lbs of rotating mass. My hard spot is aluminum does expand and contract different, are these the and long distance friendly? Or is this something that ill have to worry about losing bearing preload the longer I drive/tow?

Ill be ditching my 10 wides for a forged 9", with the possibility of radials and bogarts. I don't know the x-access theory, hopefully narrowing distance out from the hub helps too.

Up front the truck has all poly bushings, upper tubular ucas double adjustable qa1's. I've been debating on doing double adjustable in the rear and relocating both shocks behind the axle. With long bars I'd imagine I'd be safe to, would prefer clarity on that. Towing/braking forces definitely come to mind, losing towing capability isn't exactly an option.

Other than that whatever "weight reduction" I can do without gutting it I'm all ears for. Truck is 6880 without me in it
 

gmduramax

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Jun 12, 2008
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Hmmm seeing dirty hooker has it listed for drag racing or sled pulling, I would say they’re plenty strong. I wouldn’t think they would get hot enough to ever cause an issue but 🤷🏻‍♂️
 

Chevy1925

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I don’t think I would run aluminum hubs and tow heavy. That’s a ton of force over a long period of time that won’t be checked often like a race truck would. Deflection very well could become an issue. I would be checking them every 500-1000 miles for a while. Just doesn’t give me the warm fuzzies

For wheels, get the tire in under the fender as far as possible. The more flush that hub is with the outside of the wheel, the less leverage you have on the steering and suspension components. You can pick up a ton of 60ft time just from a wheel change like you are doing

Since you are not running cal tracs and just single axle wrap bars, that really all they are… axle wrap bars. Shocks straight up and both in the back would be a good place to start for cal tracs down the road. Mount them as far out toward the tire as possible to help with towing sway. To get enough length, they will probably go through the bed. Leaning them back too much will hurt your valving and its ability to do what you want them to.
 
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TheBac

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IMO, once you get to the point you're at, you've got to decide if its a race truck or a street truck. Everything you do from this point forward makes it less street truck and more race truck, and those two things generally arent compatible.
 

LSxBakakos

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May 29, 2022
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I don’t think I would run aluminum hubs and tow heavy. That’s a ton of force over a long period of time that won’t be checked often like a race truck would. Deflection very well could become an issue. I would be checking them every 500-1000 miles for a while. Just doesn’t give me the warm fuzzies

For wheels, get the tire in under the fender as far as possible. The more flush that hub is with the outside of the wheel, the less leverage you have on the steering and suspension components. You can pick up a ton of 60ft time just from a wheel change like you are doing

Since you are not running cal tracs and just single axle wrap bars, that really all they are… axle wrap bars. Shocks straight up and both in the back would be a good place to start for cal tracs down the road. Mount them as far out toward the tire as possible to help with towing sway. To get enough length, they will probably go through the bed. Leaning them back too much will hurt your valving and its ability to do what you want them to.
As far as the hubs that was definitely my biggest concern. I hate positive offset however I think x9 and zero would look better and hopefully react better. Best 60" is a 1.69 so far. I originally wanted caltracs however I've heard horror stories of towing with them which is why I went long bars instead. I had the SRD assassin bars on my old LS truck and they worked flawlessly(caltrac but with more adjustment) and netted a 1.58 60 in 2wd on 35s, sadly I don't think they'd handle the torque. As far as the shocks that sounds like what I'm after so maybe I can go this route afterall. I'm a welder by trade so I'm not opposed to cutting the stock upper x-member out in place of some dom. Some days I do wonder what pyos and 285s would net me as a gain in e.t.

IMO, once you get to the point you're at, you've got to decide if its a race truck or a street truck. Everything you do from this point forward makes it less street truck and more race truck, and those two things generally arent compatible.
You're not wrong boss, that's the dilemma I fight daily lol
 

malibu795

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Apr 28, 2007
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I don’t think I would run aluminum hubs and tow heavy. That’s a ton of force over a long period of time that won’t be checked often like a race truck would. Deflection very well could become an issue. I would be checking them every 500-1000 miles for a while. Just doesn’t give me the warm fuzzies

For wheels, get the tire in under the fender as far as possible. The more flush that hub is with the outside of the wheel, the less leverage you have on the steering and suspension components. You can pick up a ton of 60ft time just from a wheel change like you are doing

Since you are not running cal tracs and just single axle wrap bars, that really all they are… axle wrap bars. Shocks straight up and both in the back would be a good place to start for cal tracs down the road. Mount them as far out toward the tire as possible to help with towing sway. To get enough length, they will probably go through the bed. Leaning them back too much will hurt your valving and its ability to do what you want them to.
Aluminum hubs have been around for few decades in the heavy truck industry.. now how they compare, IDK.
 

LSxBakakos

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Aluminum hubs have been around for few decades in the heavy truck industry.. now how they compare, IDK.
I was about to contact IMS on my break, looked under faq's. In case anyone else was wondering it states they are intended for performance use only, not daily driving, street or towing. So I guess those are fully out of the question lol
 
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gmduramax

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Jun 12, 2008
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I was about to contact IMS on my break, looked under faq's. In case anyone else was wondering it states they are intended for performance use only, not daily driving, street or towing. So I guess those are fully out of the question lol
I was really looking forward to losing 28lbs of rotating mass. I wonder if they’re saying that for liability. It really can’t be any worse than running Chinese spacers on a dually towing a 20k fifth wheel.
 
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LSxBakakos

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I was really looking forward to losing 28lbs of rotating mass. I wonder if they’re saying that for liability. It really can’t be any worse than running Chinese spacers on a dually towing a 20k fifth wheel.
I was too to say the least. 28lbs is a significant gain in general, not to mention i would've saved about 22lb per rear side switching wheels and hubs. The expansion and contraction is what gets me uneasy. If anyone wants to tow 10k across a few states and let me know how it goes I'm all ears lol
 

2004LB7

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I was really looking forward to losing 28lbs of rotating mass. I wonder if they’re saying that for liability. It really can’t be any worse than running Chinese spacers on a dually towing a 20k fifth wheel.

I was too to say the least. 28lbs is a significant gain in general, not to mention i would've saved about 22lb per rear side switching wheels and hubs. The expansion and contraction is what gets me uneasy. If anyone wants to tow 10k across a few states and let me know how it goes I'm all ears lol
28 lbs may sound like a lot but remember it's at the very center of the wheel where it has the least affect on the rotating mass. I would bet just a few lbs at the tire is more then enough to offset the weight savings at the hub

And I wouldn't compare it to cheap Chinese spacers because even though are backed up by the steel hub reducing flex and stress
 

Bbuchanan11

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I have ims brakes all the way around my truck with street rotors as I do drive it on the street a lot. As far as for anything towing unless they did a different design on the rear hub and can use a factory style rotor you will lose your emergency brake.
 

LSxBakakos

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28 lbs may sound like a lot but remember it's at the very center of the wheel where it has the least affect on the rotating mass. I would bet just a few lbs at the tire is more then enough to offset the weight savings at the hub

And I wouldn't compare it to cheap Chinese spacers because even though are backed up by the steel hub reducing flex and stress
You make a good point there sir. Hopefully going from a x10 -24 to a x9 0mm nets some gains, I know going from my kuhmos to toyos would shave some weight too, just don't know how well they work being a 500 tread wear.

I have ims brakes all the way around my truck with street rotors as I do drive it on the street a lot. As far as for anything towing unless they did a different design on the rear hub and can use a factory style rotor you will lose your emergency brake.
Do you have their hubs as well? Or just their brake kit?
 

Bbuchanan11

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No I don’t tow at all with this truck it’s a street/race truck. And I’ll have to check out dhd’s website and see if they came out with a different design.. I got my kit back in February of 2020
 
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Bbuchanan11

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IMG_0632.jpegI’m sure you could probably slide a factory rotor over that but the rotor bolts to the back. The only kit I saw on dhd website I could still see the flanges for the rotor.
 
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LSxBakakos

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Good possibility I looked past it. Granted mine only is out a few months a year, I just can't afford to go that race at least yet lol. That's a killer looking setup though man 👌
 
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darkness

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28 lbs may sound like a lot but remember it's at the very center of the wheel where it has the least affect on the rotating mass. I would bet just a few lbs at the tire is more then enough to offset the weight savings at the hub
Rotating mass might not be much, but the unsprung weight it huge.
 

2004LB7

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Rotating mass might not be much, but the unsprung weight it huge.
Can't argue with that. But will that really help much on the strip? Maybe on a racetrack or uneven surface where suspension and turning is important then I can see more benefits. But lightweight hubs are probably going to be similar in gains to stripping weight off the frame or body. If you are at the point of aluminum hubs you are probably running a full race queen
 
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