Olive - Meanderthal’s BS BL

[Meanderthal]

I gave you visual aids with actual dimensions, not a wikipedia page with arbitrary and non BS specific specs. Believe what you choose but Ford engineers designed the bronco sport to handle and react with a specific scrub radius, my suggestion is to maintain it and put less stress on the already cheap made in china wheel bearings but do what ever floats your boat.

Edit: I'm not sure you understand the purpose of scrub radius especially for braking. In emergency braking, if one front tire has more traction than the other, a very positive scrub radius could produce a significant yaw meaning the your bronco sport will not brake in a straight line.

The issue is we don't know what the scrub radius is and your graphics only show what we already know, that a spacer will move the tire/contact patch out. Those graphics also show that you can get wider wheels/tires that keep the center of the contact patch in the same position while moving the outside of the tire out, which would maintain the scrub radius as you have proposed. Overall, neither of us has info specific to the BS.

You clearly fall into the camp of leaving what the engineers did exactly as they did it. That is okay and we are all free to do what we want with our vehicles. Engineers also have to design with the knowledge that consumers are going to change things. I'm not saying that they designed for accommodating an extra 1" of offset but I'm sure they designed in for some.

As I said, I'm sure that by adding the wheel spacer we are changing the scrub radius from a something small either positive or negative to something more positive without being a "large positive", given the reference of 4" being large.

Sponsored

 

[RogueRodney]

Meanderthal / FakeCowboy:

First, thank you both. I'll be honest, it's going to take me abit to internalize what you just presented, but very impressed by the conversation and appreciate the information.

Visually, I do like the Spacer look, but clearly I need to look at what you are discussing with the Scrub Radius.

I find it interesting what you said about braking and yaw. Could this happen with acceleration as well?

I've noticed that when I aggressively accelerate, about 45% of the time the Bronco Sport pulls to the left (driver's side). About 20% it pulls right. Sometimes it doesn't pull at all.

I've found this strange, but it doesn't seem to be based on road condition. It's kinda like driving a Fokker Dr.1 Triplane...

RR

 

[Meanderthal]

Meanderthal / FakeCowboy:

First, thank you both. I'll be honest, it's going to take me abit to internalize what you just presented, but very impressed by the conversation and appreciate the information.

Visually, I do like the Spacer look, but clearly I need to look at what you are discussing with the Scrub Radius.

I find it interesting what you said about braking and yaw. Could this happen with acceleration as well?

I've noticed that when I aggressively accelerate, about 45% of the time the Bronco Sport pulls to the left (driver's side). About 20% it pulls right. Sometimes it doesn't pull at all.

I've found this strange, but it doesn't seem to be based on road condition. It's kinda like driving a Fokker Dr.1 Triplane...

RR

Look into "torque steer", that's another rabbit hole to go down.

 

[RogueRodney]

Team:

Beginning to see why my kids don't read....

Scrub Radius Explained:

Again, thanks for calling my attention to this (and torque steer).

RR

 

[Meanderthal]

Team:

Beginning to see why my kids don't read....

Scrub Radius Explained:

Again, thanks for calling my attention to this (and torque steer).

RR

Rodney's link was not working for me, but just in case someone else is interested, here is a video I found.

 

[Mark S.]

I've found this strange, but it doesn't seem to be based on road condition. It's kinda like driving a Fokker Dr.1 Triplane...

RR

Please tell me that you have driven one of those Fokkers!

 

[RogueRodney]

Mark S.:

I'm a ground pounder man, can't stand "losing my stomach."

I made the reference because I do play video games (I know I'm a nerd, that is how I became a data analyst).

I used to play "Red Baron" if anyone remembers when they used to make good games (not this twitch crap my kids play).

Anyway, I remember the Fokker Dr. I's were called widow makers because they were inherently unstable and pulled sharply to the left and down. Inexperienced pilots would freqently crash when taking off.

This was a pretty signficant design flaw, but the Aces LOVED IT. Because they could spin around lightning fast (to the left, the right sucked) and come up on an enemies tail to blow them away.

When I first noticed this trend in my BS (the car) I almost took off the rear end of the car that I was trying to pass, and that was what leaped to mind.....

OK, it's a lame cop out for what I think you were referencing, but I don't mind being a nerd and it feeds my kids, dawg, girlfriend, etc...

Anyway, I've found it odd that I haven't seen anyone else reference it on here.... is it just my ride? Maybe I just drive like a dumb ass....

RR

 

[Meanderthal]

Mark S.:

I'm a ground pounder man, can't stand "losing my stomach."

I made the reference because I do play video games (I know I'm a nerd, that is how I became a data analyst).

I used to play "Red Baron" if anyone remembers when they used to make good games (not this twitch crap my kids play).

Anyway, I remember the Fokker Dr. I's were called widow makers because they were inherently unstable and pulled sharply to the left and down. Inexperienced pilots would freqently crash when taking off.

This was a pretty signficant design flaw, but the Aces LOVED IT. Because they could spin around lightning fast (to the left, the right sucked) and come up on an enemies tail to blow them away.

When I first noticed this trend in my BS (the car) I almost took off the rear end of the car that I was trying to pass, and that was what leaped to mind.....

OK, it's a lame cop out for what I think you were referencing, but I don't mind being a nerd and it feeds my kids, dawg, girlfriend, etc...

Anyway, I've found it odd that I haven't seen anyone else reference it on here.... is it just my ride? Maybe I just drive like a dumb ass....

RR

It’s definitely there for me, you’re not alone, I guess I am just growing accustomed to it and know that it can happen so I’m prepared to counter it.

 

[Bro_Spo]

Mark S.:

I used to play "Red Baron" if anyone remembers when they used to make good games (not this twitch crap my kids play).

Salute! Former Red Baron 3D multiplayer ace here. Spent many late nights flying sorties over the trenches. Good times...

 

[Mark S.]

Mark S.:

I'm a ground pounder man, can't stand "losing my stomach."

Oh well, thought I'd ask. I've been flying since the early 80s, and I love everything aviation. The only time I ever came close to losing my stomach was at the end of my USAF career. My wife arranged an incentive flight for me through my Wing Commander. I was stationed at Grand Forks, AFB at the time, and my Wing Commander was good friends with the Squadron Commander of the ND ANG unit based at Fargo. They called themselves the Happy Hooligans, and they were flying F-16s at the time. The few people on this planet who get to fly fighters for a living are truly the luckiest people alive.

Anyway, I remember the Fokker Dr. I's were called widow makers because they were inherently unstable and pulled sharply to the left and down. Inexperienced pilots would freqently crash when taking off.
When I first noticed this trend in my BS (the car) I almost took off the rear end of the car that I was trying to pass, and that was what leaped to mind.....

Anyway, I've found it odd that I haven't seen anyone else reference it on here.... is it just my ride?

No, it's not just your ride. It's called torque steer, and it happens with any front wheel drive vehicle configured like the Bronco Sport with a transverse-mounted engine. This configuration requires different length shafts connecting the front wheels to the transmission, generating unequal torque. Unequal torque means one wheel pulls harder than the other, causing the car to pull one way or the other. Torque steer has largely been tamed in modern cars via computer-control of power delivery—manufacturers call it "traction control" & "stability control." The Bronco Sport is relatively short and light, which increases the effects of torque steer. I suspect Ford's implementation of traction and/or stability control (I don't know which system Ford uses to combat torque steer, maybe both) for the Bronco Sport simply cannot keep up with the physical demands with the more powerful 2.0L engine. I don't believe I've heard anyone with the 1.5L complain about torque steer.

It's funny that you compared the Bronco Sport's handling to the Fokker Dreidecker—the human brain really is capable of making remarkable connections! To your point: each does suffer some instability, and interestingly, for similar reasons (albeit due to different mechanisms). Each is a rather short-coupled vehicle with a relatively powerful engine. For the Dreidecker, the direction of propeller rotation generates torque which tends to cause a roll to the left. Additionally, the prop wash swirls around the fuselage to impact the left side of the vertical stabilizer which tends to push the nose to the left. If left unchecked, the Dreidecker would fly in a constant bank and yaw to the left. As you note, it made the aircraft turn incredibly fast to the left.

Something the game designers left out of the equation, however, is that the Dreidecker was very light, which when coupled with the powerful engine gave it a much better climb rate than contemporary aircraft. Contrary to popular myth, most aerial victories in WWI did not come from fighter pilots twisting and turning in dog fights against other fighters. They came from diving gun passes against larger and slower aircraft, followed by zoom climbing (converting airspeed gained in the dive to altitude) away from any pursuers until in a position to make another gun pass. The Dreidecker's climb rate provided a substantial advantage under those circumstances.

The dive, shoot, zoom climb tactic eventually became the blueprint which drove pursuit/fighter aircraft design for next several decades. It was the tactic of choice for Allied airmen in the Pacific theater. The Mitsubishi Zero was an incredibly maneuverable fighter aircraft, but the P-38 Lightning was much faster, and could climb much higher. U.S. P-38 pilot and Ace Richard Bong used this performance disparity to ruthless advantage against Japanese aircraft, earning 40 kills to become the country's top WWII ace.

 

[RogueRodney]

I made some graphics for you. Compare the first graphic using the stock wheels along with a 25mm spacer, you get 25mm of additional poke obviously but you ruined your scrub radius. Now compare that with an 8.5" wheel with the same 37mm offset, you only get about 20mm of additional poke but you at least maintain your scrub radius, it's a much better/safer compromise

FakeCowboy:

Would you mind breaking this out as a seperate thread (think you should get the credit for the excellent work you did), maybe something titled around Spacers: Safety and Implications?

This is really good information, and I think others should understand what they are getting into by installing spacers.

For myself, I opted into Spacers through ignorance, and the utility (warm fuzzies...) I get from looking at the more aggressive position of the tire with my bolt on fenders means I likely won't pull them even though it forces me to use the 235 tires.

That said, I do plan on doing a test as soon as possible to see the impact of a critical stop at speed (I live in Texas pretty easy to get up to speed on a highway out here).

I'll post what I encounter.

Much thanks for everyones information, I truly appreciate your insights....

RR

 

[Oval Office]

Thanks for the photos of the back side of tow hooks, Meanderthal. Looks like with just a small modification I can have both, hooks and nudge bar, I can wait!!!

 

[Winds of Change]

Thanks for the photos of the back side of tow hooks, Meanderthal. Looks like with just a small modification I can have both, hooks and nudge bar, I can wait!!!

What are you working on? I am interested.

 

[Oval Office]

2022 BL cactus gray- put Mickey Thompson’ tires , roof rack, skid plate, waithimg on a ranger lift nudge bar, I see I can do some mods to tow hooks and have both— trying to do a theme for the early broncos that was raced, strope- Holman Moody- Parnelli Jones-M/T

 

[Oval Office]

Sponsored