TRYING to fit 40's on a Bronco Raptor! I have a problem! - By TCcustoms

TurboS

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8 minute review video including Eibach Pro-Lift-Kit install, 40's, on-road ride quality/driving feel, and zero to 60 times before and after.

"Today we are installing the Eibach Coil Spring Lift kit to hopefully fit 40 inch tires on Mitchells Bronco Raptor! We headed to TCcustoms in Pell City to get this lift kit on and the 40 inch tires. Drum roll.... the 40 inch tires fit! So how do these 40 inch tires affect the Bronco Raptor now? The tires are a little bit louder on the interstate, the 0-60 test went from a 5.4 to a 6.0, and the fuel economy went from a 15.1 to a 13.5 MPG."



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It looks like the Eibach springs are the way to go! If it cleared those 40-inch tires then the 39-inch BFG K02s shouldn't have any clearance issues.
 
It cleared them steering wise, but he did say that he would have to trim for full articulation. I had the same spring kit put on yesterday with 38's and it may be able to fit 40's, but I don't even want to know what would be ripped off if he jumped it with those 40's on there. HA. I think the 38's fit nicely with it size and looks wise. 40's would be cool though. I just didn't want to lose performance when I went up in tire size. I would almost bet this 38 is almost the same size as the BFG 39". They seem huge in person compared to the stock 37's.
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It cleared them steering wise, but he did say that he would have to trim for full articulation. I had the same spring kit put on yesterday with 38's and it may be able to fit 40's, but I don't even want to know what would be ripped off if he jumped it with those 40's on there. HA. I think the 38's fit nicely with it size and looks wise. 40's would be cool though. I just didn't want to lose performance when I went up in tire size. I would almost bet this 38 is almost the same size as the BFG 39". They seem huge in person compared to the stock 37's.
Those 38s do look big! How do the springs and tires feel so far?
 
It cleared them steering wise, but he did say that he would have to trim for full articulation. I had the same spring kit put on yesterday with 38's and it may be able to fit 40's, but I don't even want to know what would be ripped off if he jumped it with those 40's on there. HA. I think the 38's fit nicely with it size and looks wise. 40's would be cool though. I just didn't want to lose performance when I went up in tire size. I would almost bet this 38 is almost the same size as the BFG 39". They seem huge in person compared to the stock 37's.
Which tires and size do you have? Also what offset are your rims?

Im looking to go a little higher/bigger when my K02s get closer to end of life. But…..Im pursuing it for enhanced capability not looks (okay maybe a little bit for looks ha ha) so I’m very reluctant to lose articulation or my flares on a (reasonable) jump. I can accept lower 0-60 and mpg.

TIA
 
Those 38s do look big! How do the springs and tires feel so far?
Driving to and from work yesterday and today I must say it feels a little different. Not really in a bad way though. It definitely feels taller which I’m sure I’ll get used to. It seems to actually take bumps in the road better now than it did, but it feels a little more, and I’m trying to find a good way to describe this, disconnected. It rides better/ smoother, but it just has a slight lifted truck numbness kind of feel to the wheel now. It doesn’t move all over the place or anything and drives true. It just has a different feel to it. I did kind of totally change the springs on all the shocks and put bigger tires and new wheels on it so I get it. Like he says in the video the vehicle doesn’t nose down as hard when you brake now and the springs do feel like they are great quality. Overall I’m happy with it and will probably just need a little time getting used to the way it feels now. I’ll give a better review when I’ve put more than 40 miles on the set-up.
 
Which tires and size do you have? Also what offset are your rims?

Im looking to go a little higher/bigger when my K02s get closer to end of life. But…..Im pursuing it for enhanced capability not looks (okay maybe a little bit for looks ha ha) so I’m very reluctant to lose articulation or my flares on a (reasonable) jump. I can accept lower 0-60 and mpg.

TIA
I went with Innov8 G600 simulated beadlock wheels. I’m not sure on the offset. It is whatever came standard for this lug pattern. The tires are 38x13.5x17 Falken Wildpeak R/T. They are basically between an AT and MT tread wise. Driving 75mph on them this morning they did have a slight hum to them, but nothing like a true mud terrain would have. I can barely hear it over the wind noise and I didn’t have to raise the stereo up louder to drown it out. Not to mention the were almost half the cost of a BFG 39”. The reason I went with 38” was because before the springs came out it was going to be collars. RPG said 2.25”F and 3” rear lift to clear 38’s without losing performance. These springs gave me 2.2” up front and a little over an inch rear to keep it level. My thought was with knowing how big they wanted me to go collar wise to fit them and not lose performance off road and capability wise I better not go to a 39”. A 39 may clear all around at full stuff, but I didn’t want to find out the hard way with that. Plus I still wanted to fit in my garage and I was able to doing this by about 1.5”.
 
I went with Innov8 G600 simulated beadlock wheels. I’m not sure on the offset. It is whatever came standard for this lug pattern. The tires are 38x13.5x17 Falken Wildpeak R/T. They are basically between an AT and MT tread wise. Driving 75mph on them this morning they did have a slight hum to them, but nothing like a true mud terrain would have. I can barely hear it over the wind noise and I didn’t have to raise the stereo up louder to drown it out. Not to mention the were almost half the cost of a BFG 39”. The reason I went with 38” was because before the springs came out it was going to be collars. RPG said 2.25”F and 3” rear lift to clear 38’s without losing performance. These springs gave me 2.2” up front and a little over an inch rear to keep it level. My thought was with knowing how big they wanted me to go collar wise to fit them and not lose performance off road and capability wise I better not go to a 39”. A 39 may clear all around at full stuff, but I didn’t want to find out the hard way with that. Plus I still wanted to fit in my garage and I was able to doing this by about 1.5”.
Thank you. The INNOV8 G600s 17” 6x13 appear to be available in +25, +6 (that’s what I’m running on my beadlocks) and -6. Eyeballing the pics I’m guessing you’re in the +6.

I’m not too worried about the noise, with the removable top and my lights, it couldn’t be a whole lot worse. I’ll look into those Wild peak R/Ts, but I’ve been pretty happy with the K02s for the terrain I hit the most. Be nice to get the K02 39s if they’re really closer to the Falken 38s in height.

by any chance did you do any before and after measurements on your change in overall height front and back. Just curious.
 
Thank you. The INNOV8 G600s 17” 6x13 appear to be available in +25, +6 (that’s what I’m running on my beadlocks) and -6. Eyeballing the pics I’m guessing you’re in the +6.

I’m not too worried about the noise, with the removable top and my lights, it couldn’t be a whole lot worse. I’ll look into those Wild peak R/Ts, but I’ve been pretty happy with the K02s for the terrain I hit the most. Be nice to get the K02 39s if they’re really closer to the Falken 38s in height.

by any chance did you do any before and after measurements on your change in overall height front and back. Just curious.
Sure did. Go to the Eibach springs thread on the forum and I posted that up last night.
 
How do the CV angles look after these springs? From a working standpoint, the CVs have alot of angle from the factory. Any spring or puck lift will only increase that angle. Granted this is better on a raptor with the longer A-arms, but can still cause premature wear...
 
How do the CV angles look after these springs? From a working standpoint, the CVs have alot of angle from the factory. Any spring or puck lift will only increase that angle. Granted this is better on a raptor with the longer A-arms, but can still cause premature wear...
That's a good point! I wonder if @GregFoutz has encountered any CV binding issues during his suspension testing?
 
It does look a little steeper to say the least. I am having RPG UCA's and half tie rods put on this morning. I will report back if I notice any difference steering or ride wise with them.
 

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It does look a little steeper to say the least. I am having RPG UCA's and half tie rods put on this morning. I will report back if I notice any difference steering or ride wise with them.

I hope that picture is at full droop... the upper joint looks like its at it's max. Steering and CV look maxed out as well.

The full springs don't provide any more travel, but the CV joints will be at a higher angle of operation during aormal driving conditions.
 
I hope that picture is at full droop... the upper joint looks like its at it's max. Steering and CV look maxed out as well.

The full springs don't provide any more travel, but the CV joints will be at a higher angle of operation during aormal driving conditions.
I think that is on the ground. Definitely a side effect of those springs in my opinion. I am almost tempted to remove them and do collars, but I am not sure if that will do me any good either.
 
I think that is on the ground. Definitely a side effect of those springs in my opinion. I am almost tempted to remove them and do collars, but I am not sure if that will do me any good either.
I take that back. Picture was at full droop. They just dropped it back off at my office for me and it isn’t nearly as bad of an angle. I’ll take some better pics of it tonight. One of the ball joints is making a slight noise so they have already ordered a new one to replace it and make that go away.
 
I think that is on the ground. Definitely a side effect of those springs in my opinion. I am almost tempted to remove them and do collars, but I am not sure if that will do me any good either.
Collars or springs will have the same impact on the CV and steering angles if both are roughly the same 'lift'. The springs will provide different rate that the stock ones- presumably they were designed that way.

If you compare the Raptor to a standard Bronco or sasquatch, you can see a dramatic difference in angle of the CV as Ford gained lift via taller springs or coilovers. They didn't lower the differential. The Raptor design reduces stress somewhat as the longer length of the suspension eases the angle and it's changes as the suspension cycles.

Look forward to the pics!
 
On the ground pics. Definitely not as sharp of an angle. Steering wise it feels good. I will say the one thing I notice is when you do turn the wheel it doesn't rebound back to straight on it's own as easily as it did before. It does feel a bit "smoother" than stock though turning the wheel. I like it, but not a noticeable huge difference. As far as ride in general with these Eibach's and 38's it is definitely firmer than stock. I am not sure if that is mostly the springs or tires ort both. I almost think it is the tires. I have gone to running them at 30PSI all the time now since 40 felt way over inflated. I was hoping the springs would break in a little over time and soften up some. I wish I could try running a set of 39" KO2's for a day or swap these for the stock springs and collars for a day and see which is better. Oh well, if fox ever comes out with factory race coilovers for these I am jumping on that band wagon.
 

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So I crawled under my truck with stock suspension and stock tires to check the angle on the axle this morning. I used the measure app on my iPhone by placing it on the axle with the wheels straight on level garage floor. I got 6-7% declination on the axle.

Curious if anyone with a lift (Foutz collars, RPG spacers, Eibach or Hyperco springs) has or will measure theirs? What’s the angle and lift?

Anyone have an idea of max % declination on the axle would be in the “acceptable” range?

if you ever wondered what retired people do in the morning……
 
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From an engineers perspective, the CV & steering angles is a part of the design and engineering constraints/criteria for the Eibach springs as with any other suspension component. The +2.6" front and +1.1" lift these springs provided would be a result of that engineering criteria and a year of testing.

Quoted from Eibach.com (link to site below): "Eibach's PRO-LIFT-KIT springs are developed using championship winning off-road race technology providing maximum lift without compromising factory components or ride quality."



With that said, keep in mind it's possible to break anything as every mechanical item has a failure point. The larger tires and custom wheels with non-OEM offset, that the spring lift enables and we all love, will increase stress on suspension components far more than a engineered and tested spring lift.
 

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