DIY Custom Long Travel Build

Hello everyone, I've been wanting to build my own long travel set up for my 2010 Tacoma 4wd but am a bit slack on the geometry that goes into it. I'm familiar with roll center, scrub radius, King Pin Inclination etc but am not familiar with how to use that information to build my own. Any advise on how to measure for, design and build a set up?

Right now im running total chaos stock replacement uppers and king 10 in coilovers in the front. get the job done but am always left wanting more and am always scared to goes ball deep and really brake something.

I am familiar with some CAD such as Fusion 360

I have welding and fabrication experience but am completely lost on where to begin in this process. Wanting to build at least a 4.5+ with around 14+ inch of travel.

 

There is no King pin in a SALA suspension. You may need to get familiar with the type of suspension you have and then read up on it. There is a lot to consider if you are wanting to do something more than just add length to the control arms.

Best suggestion would be to just purchase a kit that someone has already done all the math for unless you have a really good grasp and understanding of suspension.

 

I am familiar, I know there is no king pin. King pin inclination is within the angle of the spindle AKA steering axis. It correlates directly to scrub radius.

 

I understand the majority of the terminology but and confused on where to start on my own build. ex. how long do my uppers/lowers need to be. What my KPI should be. Distance between upper/lower balljoints (or uniball), where and how to mount on frame, etc.

 

I would do some more research then if you are going to get into changing mounting locations. You'll have antidive angles to consider, instant centers, etc. Also wherever you got that pic that says kingpin inclination as where you are getting your terminology I would consider going with a different source that uses correct terminology for suspension.

 

Where could I get my hand on some good information like that. I recently purchased race car vehicle dynamics aka “the Bible” but the math is pretty intense. Any other suggestions?

 

Yep that's what you're gonna have to deal with if you want to do a complete overhaul like you are describing in moving mounting points and getting stuff right. Just google suspension design lots of good books come up. The funny thing is most are old but not much has changed in the math dept. just the materials. It's not easy when you start trying to factor in the dynamic factors of suspension. Static is easy. Hell getting links and solid axles is easier than SALA. You have to deal with camber gain, bump steer, etc.

Now if you want an easy route then just buy a kit that is that wide. They did all the math and R&D to get it to that point. Also how are you running 10" travel shocks on the front of the truck? Most LT kits are only 8" travel.

 

Start here

https://www.tacomaworld.com/threads/long-travel-bs-thread.109317/

 

Had the intentions of making a long travel set up in the future so when I got the total chaos uppers I went ahead and ordered the 10” shocks with it. Slightly limited on up travel in the front but my tires rub on the inner fender before the shocks “bottom out” in the uptravel

 

Your axle angles must be something fierce and still 10" on a LT kit is a really long shock I thought they were all 8"

 

Not terrible. The shock just never fully extends. I had a wreck a while ago and my phone broke in the process so I Don’t have many pictures of the truck currently but will upload some soon that may help.

 

You have OEM length front coilovers.


It would be impossible to fit 10” coilovers with stock LCA’s

 

Looking to do a smililar set up to this

Boxed upper and lowers with custom spindle while keeping the 4wd. Probably gonna use 1” uniball on the top. Not sure about the bottom. Have heard some use 1, 1.25, or 1.5” uniball (any suggestions?) with 3/4” heims on the upper control arm and undecided for the bottom. Probably just sleeve it with a bushing to connect to frame at factory mounts if possible. Would like to stay away from kits.

 

He doesn’t have 10” shocks, not even 8”

The oem bolt in shock length is somewhere around 6”

 

I think you are biting off more than you can chew. Btw that set up would suck on the street. There is little to no anti dive. The instant centers look like they're not really going to be corner friendly. Just looking at the pic and the control arms being fairly parallel

 

Yeah I think he was talking about the rear now with those pics he posted. OP doesn't really know what he's getting into.

 

Apologies ✋ the fronts are 8” and the rear 10” Will continue to tread through some books on suspension design to learn more about it. Anyone know of some online simulators to play with?

 

Still 8" is for the LT still don't think you can stuff that in stock form. Might want to look at your front coilover part #s and see.

 

You don’t have 8” shocks.
8” is ONLY for lt. You have oem front coilovers ~6”