Lift Height Questions For Fox 2.5 C/O's

I bought my truck used with an aftermarket front bumper already on it and I'm about to install Fox ext. travel 2.5 non-resi C/O's with Dakar medium rear packs. I've read stock height is ~20.5" front and ~22" rear. Most lift theirs to ~23" front and ~24.5" rear. (~ for this means give or take a quarter inch).
My dilemma is I know my measurements will be off due to this front bumper. I've searched my ass off but still have couple questions I have about installing this lift:
Do we know for a fact that Fox ships the 2.5 ext. travel C/O's at 2" lift from the factory?
Is it fact that 4 turns = 1/2" lift?
Since I went ext. travel and UCA's, what's the highest I can safely lift (2.5", 3", 3.5", etc.)?
After lift is installed, how high should I be able to jack the front up before the front tires come off the ground (droop)?
I found a couple answers to similar questions of mine but none were pertaining specifically with already having an aftermarket front bumper or the ext. travel C/O's.
Thanks!

 

You can adjust the coil overs to your pleasing after they are on. However Fox will have a listed max number of inches you should have of threads showing. If your front bumper is heavy you can always get stiffer springs. That will set you up higher with less adjusting. Just play with it when adjusting. 4 full turns should give you close to .5 inches but may be different with a heavy front bumper. You don't want to crank them to high because of the max preload and it will be a stiffer ride. Also the higher you go the more wear it puts on your other components. I could be wrong on this but your preload I think effects how much droop you have when the tire is off the ground.

 

Just measured mine straight from the factory. Their set @ 26 threads & 27 threads. That doesn't coincide w/everything I've read where they come from Fox set @ 2"/ 16 threads.

There is exactly 2" of threads exposed between the bottom of the tophat and the top of the adjustment collar.

Any idea what this equates to?

 

No... I have Icons. They should be adjustable past what they come set at. You just have to read what the max preload is. For Icon with 650lb springs it's 2.13 inches.

 

Unfortunately, there is no way to know what lift you will get, exactly, from 2" of initial preload. It depends on the weight of your truck, and what the real spring rate is of your springs. In general, 1/2" of adjustment (four rotations of the collar) equals 1" of lift, but that relationship is not exactly linear either. Most likely you will end up around 2 1/2 to 2 3/4 on the drivers side and a little less on the passenger side (collar to top hat). I would not go over 3" of lift on the extended travel set-up. Doing so will probably reduce your rebound travel to unhealthy levels. If you need more that 2 3/4" of preload to get to 3" of lift, you need springs with a higher rate. Most people with heavy bumpers and/or winches use 650 or 700 lb springs. The springs that come on the fox set-up are 600.

Here is the best way to set up your suspension for proper function. With the strut removed, move your suspension to the top of it's travel and record the measurement from the hub center to the fender. Subtract about an inch from that measurement because compression of your bump stop will actually let the suspension travel a bit farther. Now move the suspension to full droop and record that distance. The difference between the two is your total suspension travel for that geometry. It will differ some depending on what UCA you have. Armed with these numbers, you can decide where in that travel window you want to ride. Ideally, I would set the suspension to ride with no less than 2" of rebound travel. That would be your full droop measurement minus 2. If I ended up with 8" of total travel, I would probably split it 3"rebound/5" compression. Then of course you can fine tune around these numbers to get the ride height you want. In any case, I would not go above 3" total lift because your steering geometry is the other wild card. If you go too high, you will induce excessive positive camber. Dialing that out will force your caster settings to push the wheel back in the wheel well. This can have consequences for tire clearance with larger tires.

Adjusting ride height to whatever number you want without understanding what it is doing to your compression and rebound relationship, or your steering geometry is not smart if you want the suspension to perform well.

I hope this helps, and doesn't confuse you further

 

I emailed Fox with the same question and got this answer that is not an answer at all:
"Hello,

Highest lift possible will depend on the pat number shock you have, 0-2" or 0-3". Droop level will depend on suspension travel.

Thank You,"
I'd already told them which coilovers I got.
"Droop level will depend on suspension travel"....... No shit?!?!?!?

I'm used to solid axles and cycling the suspension for max compressed/extended shock length, and checking for need of bumpstops and limiting straps. This IFS is new to me but I guess I'll just cycle it thru it's whole cycle and go from there. Pretty much what badger above advised. I'd figure there'd be more concrete answers but I guess nobody has taken the time to do this. I figured Fox could tell me why some are sent with 16 exposed threads (that's supposed to equal a 2" lift) and why I received mine with 27 exposed threads (which would equal 3.5" lift according to what I've read even though they say max lift height is 3"), if 16 exposed threads actually means a 2" lift, how much droop I should have with a properly adjusted C/O, etc.
I'll do it and post back here but my numbers for final lift height will be a bit off as I have the heavy front bumper already.

 

I have the same coilovers as you....Fox 2.5 ext travel non-resi and am running LR UCA's. I ran them with factory settings for about 8 months until I put on my aluminum bumper, winch, and steel skids. With the weight from those 3, my truck was actually sitting lower than stock with the 600lb springs and coils at factory settings. Instead of adding preload, I swapped to King 700 lb springs and adjust the preload so I still had 0.5" rake from the rear. I also kept an eye on my droop while making adjustments and still have 3.5" droop with my final settings. FYI - I have Icon AAL in the recall leaf pack and I also removed my sway bar.

Not sure if that answers any of your questions at all.....but I hope it helps lol.

 

Yes it helps. Thanks!

 

Fox's customer service is pretty dismal. What they told you isn't wrong, but obviously not helpful. The droop depends on the UCAs you have. Most UCAs are designed to offer more suspension travel than stock. Sometimes even knowing the brand doesn't help because they may have changed ball joints or spherical bearings along the way. That is why, no matter what anyone tells you, if you really want to know what is going on, you have to do this yourself.

If you do have the extended travel model ( I think the part number ends in 419?), then you can get 3" of lift You can't go over that because of steering geometry problems, excessive CV axle angles, and probably loss of rebound travel.

Most likely you will need new and heavier springs. 600 pound springs are meant for stock trucks. I had to switch to 650s for my ARB bumper with a light weight winch, and others have gone to 700s. Even here, just because your spring says 600 (or whatever), doesn't mean it actually is calibrated to that rate. Eibach, who supplies the springs for Fox used to be a top notch spring, but their quality control has gone to hell. I've heard that many of their springs are now made in China. I just got back from Beijing a couple of weeks ago, and while I was there I was passed by a delivery van with "EIBACH PERFORMANCE" graphics all over it. Smoking gun? I don't know, but I'm not using their springs anymore. I would get King springs.

 

Fox said their ext travel 2.5 C/O's come from them @ 1.925" of exposed threads which equates to 3" lift.

 

So ..I have fox 2.5's ext. with dsc resi's and I have my c/o's set at 23 threads LH and 19 RH. They came set at 16 threads. I do believe they have the 600lb spring and they are a little bouncy. Now that I have them installed, I've read that these need to re-valved for a Tacoma even though they were sold for our trucks. Its not as bad as the back tho.. The rear are Fox 2.5's with ICON RXT's without the extra leaf installed. These are really bouncy and its not the springs, and I know the rear fox 2.5's are rated for up to 1.5" of lift and then I switched over to ICON RXT's which have approx 1.8" of lift.

 

Similar setup... Would like to talk to you sometime about that....

 

All good, I'm here to help out

 

Sweet, send u a pm soon!! Thanks!!

 

All good, if there's a little delay on the reply its because I work early but I'll get back to you

 

...so if its about the rear Fox 2.5 (NON-extended) shocks paired with Icon Rxt's WITHOUT the extra leaf installed. Your good cause I spoke with FOX and they said they give a little play area within their rating up to 1.5" lift in the rear. If i install or change the rear RXT (#1) setup then im going to have to sell or look into getting them rebuilt for 2.0" (rear) lift or more

 

If its about the front ext. 2.5's...

The 600lb springs have settled too much. I would like to reduce preload by installing 650lb springs but I'm on the fence because i will install a winch with sso bumper or full replacement and will need 700lb

Both the front and rear have settled as well. Mainly the front though. 600lb isnt enough

 

Yeah, kind of along those lines... The stock 600lb springs have a rough time getting me two inch lift on the front, and I only have sliders. I went with the tundra rears, redid and valved for Tacoma from accutune. My rxts seem to have me a solid 2 inches up on option one, but it's smooth. The front, have 14 inch 650 springs on now, about 3 inch up with no preload passenger, 1/2 inch driver, valved ok, but too much spring for stockish truck. Plus life just threw me a few curves, might have to let it all go here anyhow... We shall see if a few!! Thanks though!!!

 

Can anyone confirm that the Fox 2.5 with RR and 650 springs give the full 3" in the front or is it 2.5???? Any one?