Long Travel AHC (3 Viewers)

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Full sensor in the front. 1/2 lift in the rear. Front Timbrens no spacer, 24mm front spacer. No front sway.

Rear timbren spaced down 1/2in with a timbren puck spacer. 40mm top spring rear spacers, bottom shock mount raised to the next hole, 1/2 of a maxed out rear sensor lift.

Also you can see the rubbing on the upper fender before I added spaced bump stops. It was painted and as you can see the tire hasn’t touched it since I dropped them .5inches. I also needed to really cut out the rear mud flaps. They rubbed like crazy no matter what I did. At this point they just touch when I’m fully flexed. Nothing at all concerning.

Also I wheel every weekend, so it has had many many opportunities to make contact.

+25 rims. 35/12.5/17 MTs

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TeCKis300 said:
Beast. Out there tearing it up every weekend.

You probably have been flexing this setup more than the rest of us put together. Any weaknesses or improvements you're still looking for?
Click to expand...
Honestly, the only downfall is still the length of the front coil over. Anything beyond 5mph in high is useless. I ping the shock out on its droop cycle. When I’m in neutral and doing 30-40 through snow I do the same thing.

I have analyzed everything so many times and I have zero indication that things are rubbing, binding, hitting, stretching, etc. next is body lift (1.5in) and gears/f/r locker. That will make me happy for at least a year or two.


I do see myself going to a conventional set up at some point, maybe someone will come out with an extended travel/length ahc shock by then… ;)

Also, I am curious what a tundra swap, diff drop, uni balls on the upper control arms with rcv’s and 35-40mm of front spacer would handle (no sway bar). If you could pull that off you would have an amazing ahc setup, the ahc line would be a massive workaround that deep in the shock bucket.

I just love what it can do right now. All that travel, a good set of 35mts is a really great combo. It’s fast and nimble when I need it to be and it crawls with a ton of grace and control. It’s impressive what it can walk through and always have 4 tires on the ground.
 
Killacaviar said:
Honestly, the only downfall is still the length of the front coil over. Anything beyond 5mph in high is useless. I ping the shock out on its droop cycle. When I’m in neutral and doing 30-40 through snow I do the same thing.

I have analyzed everything so many times and I have zero indication that things are rubbing, binding, hitting, stretching, etc. next is body lift (1.5in) and gears/f/r locker. That will make me happy for at least a year or two.


I do see myself going to a conventional set up at some point, maybe someone will come out with an extended travel/length ahc shock by then… ;)

Also, I am curious what a tundra swap, diff drop, uni balls on the upper control arms with rcv’s and 35-40mm of front spacer would handle (no sway bar). If you could pull that off you would have an amazing ahc setup, the ahc line would be a massive workaround that deep in the shock bucket.

I just love what it can do right now. All that travel, a good set of 35mts is a really great combo. It’s fast and nimble when I need it to be and it crawls with a ton of grace and control. It’s impressive what it can walk through and always have 4 tires on the ground.
Click to expand...
If you commission a shock collar like Westcott uses but with a flat bottom and the inner diameter matched to 3.75” and a 1” ‘drop’/longer you can put a 20” 3.75” (2” lift) off the shelf shock in there. I think we decided <in the lx570 spring thread> to target mid 300s in/lb spring constant. Stock spring was 17.6” long.

Eibach id 2000.375.0350S
Length inches.inner diameter. Spring rate
 
Last edited:
Killacaviar said:
Honestly, the only downfall is still the length of the front coil over. Anything beyond 5mph in high is useless. I ping the shock out on its droop cycle. When I’m in neutral and doing 30-40 through snow I do the same thing.

I have analyzed everything so many times and I have zero indication that things are rubbing, binding, hitting, stretching, etc. next is body lift (1.5in) and gears/f/r locker. That will make me happy for at least a year or two.


I do see myself going to a conventional set up at some point, maybe someone will come out with an extended travel/length ahc shock by then… ;)

Also, I am curious what a tundra swap, diff drop, uni balls on the upper control arms with rcv’s and 35-40mm of front spacer would handle (no sway bar). If you could pull that off you would have an amazing ahc setup, the ahc line would be a massive workaround that deep in the shock bucket.

I just love what it can do right now. All that travel, a good set of 35mts is a really great combo. It’s fast and nimble when I need it to be and it crawls with a ton of grace and control. It’s impressive what it can walk through and always have 4 tires on the ground.
Click to expand...

Nice feedback.

Do you know how much front sensor lift you've dialed in? Maybe the relative travel of more constrained IFS vs flexy SA rear? Not sure what the pinging can be and not exactly sure what kind of terrain you're on. I'm regularly in low range H and when the terrain opens up I can easily get to the 50mph AHC drop-to-normal-heights threshold and it seems smooth and compliant even in the rough stuff.

Not that I need it, but I've been debating Tundra setup. Part of the challenge will get back to limited shock stroke. The Tundra arm locates the lower shock pivot further outboard adding to shock inclination. Changing the motion ratio so that any travel advantage with the longer arm is negated by the limited shock stroke. Then I get crazy ideas to use the Tundra arm modified with the shock pivot inboard decreasing motion ratio allowing the AHC shock to support the added travel. Then supplemented by a second high performance bypass shock. At that point, might as well scrap AHC. That would also mean a rig focused more on off-road loosing it rounded capability.
 
It
TeCKis300 said:
Nice feedback.

Do you know how much front sensor lift you've dialed in? Maybe the relative travel of more constrained IFS vs flexy SA rear? Not sure what the pinging can be and not exactly sure what kind of terrain you're on. I'm regularly in low range H and when the terrain opens up I can easily get to the 50mph AHC drop-to-normal-heights threshold and it seems smooth and compliant even in the rough stuff.

Not that I need it, but I've been debating Tundra setup. Part of the challenge will get back to limited shock stroke. The Tundra arm locates the lower shock pivot further outboard adding to shock inclination. Changing the motion ratio so that any travel advantage with the longer arm is negated by the limited shock stroke. Then I get crazy ideas to use the Tundra arm modified with the shock pivot inboard decreasing motion ratio allowing the AHC shock to support the added travel. Then supplemented by a second high performance bypass shock. At that point, might as well scrap AHC. That would also mean a rig focused more on off-road loosing it rounded capability.
Click to expand...
it feels like the shock fully extending.

Big whoops, big rocks at speed is where i feel it. My front sensor is maxed out (no added bracket or anything)
 
TeCKis300 said:
Nice feedback.

Do you know how much front sensor lift you've dialed in? Maybe the relative travel of more constrained IFS vs flexy SA rear? Not sure what the pinging can be and not exactly sure what kind of terrain you're on. I'm regularly in low range H and when the terrain opens up I can easily get to the 50mph AHC drop-to-normal-heights threshold and it seems smooth and compliant even in the rough stuff.

Not that I need it, but I've been debating Tundra setup. Part of the challenge will get back to limited shock stroke. The Tundra arm locates the lower shock pivot further outboard adding to shock inclination. Changing the motion ratio so that any travel advantage with the longer arm is negated by the limited shock stroke. Then I get crazy ideas to use the Tundra arm modified with the shock pivot inboard decreasing motion ratio allowing the AHC shock to support the added travel. Then supplemented by a second high performance bypass shock. At that point, might as well scrap AHC. That would also mean a rig focused more on off-road loosing it rounded capability.
Click to expand...

Moving the lower shock mount back to factory and then messing with spring rate is the best option I think. Perhaps just a slightly heavier coil spring and not necessarily a bypass. Do we know what the front spring rate is? Wonder if a custom king or eibach coil would work?
 
nwfl4runner said:
Moving the lower shock mount back to factory and then messing with spring rate is the best option I think. Perhaps just a slightly heavier coil spring and not necessarily a bypass. Do we know what the front spring rate is? Wonder if a custom king or eibach coil would work?
Click to expand...

Yup! This would be the most direct ticket to achieve more travel. I don't know what the front spring rate is and that would be a good way to do it. Perhaps using pre-load again with something like the Prescott in-coil spacer could work as a compromise, letting the AHC progressive rate handle the rest. Concern would be damping may be insufficient to match, or I guess could default more to Sport setting. The crazy hair with a secondary bypass shock would be to get more knobs to dial in the front to another level of performance.
 
Front AHC coil springs are around 325 lb-in (per the latest estimate in the spring rate thread)
The only custom piece we'd need is a spring perch like the westcott collar but set up for a 3.75" ID flat ground spring.
There could be two collar options - one that is at the place of the OEM collar, and takes a higher spring rate 18" spring; and a second that is dropped one inch and takes a standard or higher rate 20" spring for preload and/or lift (putting a 20" spring in a 19" space).

Here's a page for the Eibach spring family.
Eibach id 2000.375.0350S
 
Killacaviar said:
It

it feels like the shock fully extending.

Big whoops, big rocks at speed is where i feel it. My front sensor is maxed out (no added bracket or anything)
Click to expand...

I'm wondering if it's related to the rubber bushings in the LCA? Might have torn, or the bolts are torqued in an extended position?

They provide some resistance and damping at the ends of travel. Like when installing the coilovers, have to actively push down on the LCA at the extents of travel to make room and even then, they provide a lot of resistance enough to have to untorque the alignment bolts to actually make enough room.

Monica the race truck seems to make the LCAs work for 14"? of travel? Then again, they're replacing them regularly.
 
I called Toytec on this a couple months back trying to source the same thing and wanted to make sure the +2" would be the same +2" size for my 2018. They gave me the info of their builder and insisted I reach out to them directly. I called they were super cool and said they should be the same as the Tundra and could build to whatever length I needed. I was going to give a little extra length over what the Slee and Toytec ones were. I measured mine and was going to add 3-3.5" just to be safe in case I did the e&e and the lx600 shocks together down the road.

Here is his info for anyone that might want it. John at Crown Performance 760.599.0090

He said it would take about 2 weeks and they would be about $70-75 IIRC.
 
Jason Andrews said:
I called Toytec on this a couple months back trying to source the same thing and wanted to make sure the +2" would be the same +2" size for my 2018. They gave me the info of their builder and insisted I reach out to them directly. I called they were super cool and said they should be the same as the Tundra and could build to whatever length I needed. I was going to give a little extra length over what the Slee and Toytec ones were. I measured mine and was going to add 3-3.5" just to be safe in case I did the e&e and the lx600 shocks together down the road.

Here is his info for anyone that might want it. John at Crown Performance 760.599.0090

He said it would take about 2 weeks and they would be about $70-75 IIRC.
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Nicely done Jason! That’s the way to go 👌🏼
 
TeCKis300 said:
No doubt. Just saying changing the AHC shock position with the bracket won't change that.
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Sorry I haven't been on here in a while and just saw this. I finally installed rear shock mounts and have Timbren active bumps. You think I still need to limit travel in front or rear having the Timbren?? I am almost done screwing things up and would like to check AHC pressure. If you are able or willing to do that I would be happy to drive to you and pay for your time.

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Expoguy said:
Sorry I haven't been on here in a while and just saw this. I finally installed rear shock mounts and have Timbren active bumps. You think I still need to limit travel in front or rear having the Timbren?? I am almost done screwing things up and would like to check AHC pressure. If you are able or willing to do that I would be happy to drive to you and pay for your time.

View attachment 3356217
Click to expand...
I didn’t know you could check AHC pressure in Techstream on this generation of LX. I thought that was one thing left behind with the last LX470.
 
Expoguy said:
Sorry I haven't been on here in a while and just saw this. I finally installed rear shock mounts and have Timbren active bumps. You think I still need to limit travel in front or rear having the Timbren?? I am almost done screwing things up and would like to check AHC pressure. If you are able or willing to do that I would be happy to drive to you and pay for your time.

View attachment 3356217
Click to expand...

I don’t know if stock timbrens alone are enough bump stop.
 
You’ll need a 1/4-1/2” timbren spacer to be safe. Timbrens compress to 2.75” I believe @turbo8 measured about 3” from frame where the shock tops out. Wheelers sells Timbren spacers which is what I’m running. I’m gonna start with a 1/4” spacer
 
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