Don’t buy drop spindles?

3104 Views 51 Replies 21 Participants Last post by Shaun @ Street or Track, 4 mo ago

rusty1161

Discussion Starter · 5 mo ago

Thoughts? I think someone else figured out the geometry.

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crank1000

· #2 · 5 mo ago

I’ll be the first to admit I don’t have much experience with a lot of different suspension systems for these old mustangs, but after installing MMIs Mod 1 front end, I’ll take Mike’s word on pretty much anything. Hard to imagine any other system feeling much better.

rusty1161

Discussion Starter · #3 · 5 mo ago

crank1000 said:
I’ll be the first to admit I don’t have much experience with a lot of different suspension systems for these old mustangs, but after installing MMIs Mod 1 front end, I’ll take Mike’s word on pretty much anything. Hard to imagine any other system feeling much better.

Have you looked at @Shaun @ Street or Track coilover setup and his dropped spindles? There are a lot of users here that sound satisfied. I posted that video to further the discussion and get more feedback, from all sides.

crank1000

· #4 · 5 mo ago

rusty1161 said:
Have you looked at @Shaun @ Street or Track coilover setup and his dropped spindles? There are a lot of users here that sound satisfied. I posted that video to further the discussion and get more feedback, from all sides.

I have seen his stuff and I have no doubt it’s great. I wouldn’t even pretend to have an opinion on the engineering pros/cons of the different systems out there. I just have personal experience with Mike and his products and trust his word. The ‘70 big pin spindles he suggested worked perfectly with my Dynapros and I didn’t need to roll my fenders or worry about wheel size or clearance issues at all.

Having said that, since I’ll likely be going to EPAS soon, it would be nice if there was a standard spindle option out there with a shorter steering arm to maybe overcome RTC issues.

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Westmus

· #5 · 5 mo ago

crank1000 said:
.. it would be nice if there was a standard spindle option out there with a shorter steering arm to maybe overcome RTC issues.

The bumpsteer kits earlier sold by Pro-Motorsports did shorten the steering arms with like an 1" by moving the tie rods mounting location with an bracket bolted to the steering arm. I believe it removed ½ turn lock to lock.

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crank1000

· #6 · 5 mo ago

Westmus said:
The bumpsteer kits earlier sold by Pro-Motorsports did shorten the steering arms with like an 1" by moving the tie rods mounting location with an bracket bolted to the steering arm. I believe it removed ½ turn lock to lock.

Well that’s interesting. That might be just the ticket but it seems like finding one of those kits is gonna be tricky these days. I’m surprised this design didn’t stick around. Off down another rabbit hole I go!

Westmus

· #7 · 5 mo ago (Edited)

crank1000 said:
I’m surprised this design didn’t stick around.

Probably a combination of price and not looking cool. Despite it's a 2 in 1 solution, bump steer correction and faster steering in one easily bolt-on modification. I believe the kit was also advertised as making an slight optimizing on the ackermann angles

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Boom

· #8 · 5 mo ago

The video is educational in some aspects. I can understand when he talks about ta wider tire being more prone to lifting in the middle under the forces you'd expect driving in a turn at speed. The rest of it doesn't seem to make sense to me.

He says to stick with a 275 wide tire. That's what we're hoping to achieve WITH the spindles. So wouldn't the spindles still be our best option? I know there were some other spindles in the past, I never really looked at them (Fatman comes to mind), however the SoT spindles look phenomenal. Everything else SoT has put out has been top notch quality, so I don't see why these spindles would be any different.

Nailbender

· #9 · 5 mo ago

I ran the CSRP 1.5" drop spindles that MM was talking about for 2 autocross seasons before I swapped them out for CSRP stock hight big pin spindles. They weren't unstable or dangerous but I wanted to try the original geometry to see if it helped the car racing and it did a bit that I noticed. My friend Nick who is a much better driver than me didn't notice a difference. MM chopped up the steering arms on his spindles to shorten them as seen in the picture below.

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I don't know what math he used when he shortened the arms?

I don't know how old the video in the original post is? Was it made before Shaun came out with his drop spindles, or is he taking a swipe at a direct competitors product that he has probably never tried? I hope not.

With my underwhelming experience with my first set of drop spindles I wasn't first in line for the new SoT spindles, but with the need of faster steering and more tire I bought a set a few weeks ago. I won't know how they work until April or May but I've bought a bunch of Shauns stuff and it has always been of excellent quality and works very well! Shaun didn't hack his spindles up in his garage they were designed on a computer using modern software by people who do that sort of thing for a living. I'm hoping that makes the difference.

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rusty1161

Discussion Starter · #10 · 5 mo ago

Nailbender said:
I ran the CSRP 1.5" drop spindles that MM was talking about for 2 autocross seasons before I swapped them out for CSRP stock hight big pin spindles. They weren't unstable or dangerous but I wanted to try the original geometry to see if it helped the car racing and it did a bit that I noticed. My friend Nick who is a much better driver than me didn't notice a difference. MM chopped up the steering arms on his spindles to shorten them as seen in the picture below.

View attachment 877420

I don't know what math he used when he shortened the arms?

I don't know how old the video in the original post is? Was it made before Shaun came out with his drop spindles, or is he taking a swipe at a direct competitors product that he has probably never tried? I hope not.

With my underwhelming experience with my first set of drop spindles I wasn't first in line for the new SoT spindles, but with the need of faster steering and more tire I bought a set a few weeks ago. I won't know how they work until April or May but I've bought a bunch of Shauns stuff and it has always been of excellent quality and works very well! Shaun didn't hack his spindles up in his garage they were designed on a computer using modern software by people who do that sort of thing for a living. I'm hoping that makes the difference.

View attachment 877424

Thank you for adding to the conversation. I’m looking forward to hearing more after you get your new spindles installed and some miles under them.

The video in the OP is five months old.

jlangholzj

· #11 · 5 mo ago

We'll see if/when shaun comes in but agreed, I get the impression that he's put a lot of work into them. Additionally, its more than just "a dropped spindle", there's geometry differences too.

Nailbender said:
View attachment 877424

We can see that pretty clearly here. Moving the upper ball joint down is going to extend out what's called the "front view swing arm" which basically just means you get less camber variation in travel. Additionally, the lower ball joint is effectively staying in the same spot while the tire is moving "up". This is going to effectively flatten the angle of the "n-line" or the line from the instant-center to the contact patch approximate center. Flatter n-line means the point at which your force acts on the chassis is going to migrate less vertically as the chassis moves/rolls, which leads to more stability in the corner. The tradeoff to this is that you might need more anti-roll bar because you're also taking "anti" geometry out of the car, or there's less "jacking forces".

Suspension geometry is a ~8-headed snake eating itself. Just changing one thing on its own without considering smaller other changes doesn't lead to anything.

MM's point about tire contact patch flex has truth to it, however its independent from the effectiveness of a drop-spindle design; as-is his point about the "effectiveness" of a given design at street speeds. The whole setup, no matter the design, is a tradeoff on where and how those compromises have been made and the expectation and use case at the end of the day. Back to the tire analogy, the faster times due to the smaller section width may have implications that have nothing do to with the front geometry of the car, but rather how that geometry is balanced across the car. Additionally, a wider cross section for a given offset results in a higher scrub radius or sometimes even changing the direction of the scrub radius, which affects how the car feels under braking, etc. I'm sure this is all stuff that MM has put thought into and tried to distill down for the video and as he says, is just an explanation of "here's why we're doing it differently now".

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Shaun @ Street or Track

· #12 · 5 mo ago (Edited)

I am lucky to have our shop in the suburbs of 'Motor City' and been fortunate enough to get to know some very talented engineers. The particular gentlemen that we hired for the spindle geometry project has over 40 years OEM experience in vehicle dynamics. Everything from family sedans to sports cars, Formula SAE to race cars. When he tells me the tire is everything and getting a wider/usable contact patch on the ground is gold, I do as I'm told and listen.

First we measured the entire front end of the car. All the pickup points, suspension link lengths etc. We already had a lot of this data so not too bad.

Then, using suspension design software we were able to start developing a new spindle that would fit inside a 17" wheel, use our existing control arms AND improve the geometry.

We then had to build an entire CAD model to figure out packaging:

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We then had to sit down with our suspension engineer and CAD guy to tweak packaging and geometry. Having the geometry and CAD model was one thing but they have to play nice together. This back and forth to figure out the best geometry and what would actually fit took lots of time, many meetings and several years...

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Once the geometry would fit inside the wheel, we then had to stress test the part through computer simulation. Again, this was another round and round exercise. If a certain area wasn't up to the loads we had to modify the design and if that modification affected the geometry would have to go through the process all over again...

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My real world testing has shown that as well as fitting the wider tires up front, we are indeed using that extra contact patch. Recent trips to Road America have shown we are using all the contact patch of the 275's on our '66 and not the outer half we used to with the regular height spindles. The car is more balanced, has less understeer and is very fun to drive really fast.

The '66 drives perfectly straight even at 160mph on the race track and the 70 drives just fine around town.

I am very proud of this project. It was a big gamble and took a ton of time and money to figure out.

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LSG

· #13 · 5 mo ago

I wonder if we should view the above video as Mike saying we shouldn't buy HIS dropped spindles. Some of the very first design attempts at dropped spindles JUST moved the pin. While this is nice, everything affects everything else. I think Sean's spindles, because they are designed with help from people in Detroit, may indeed work better than Mike's. Nothing against Mike, I have lots of his Dad's stuff. But my suspicion is that the Sean spindles are better, geometry wise, because more variables were considered. Sean has access to people in the industry that California people just can't get. That said, I haven't yet bought spindles from anyone. But I have a pair of '70 big pin drum spindles, and the 4 piston Galaxie calipers, waiting for a budget infusion. And I know SoT makes the brackets I need,........ LSG

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rusty1161

Discussion Starter · #14 · 5 mo ago

LSG said:
I wonder if we should view the above video as Mike saying we shouldn't buy HIS dropped spindles. Some of the very first design attempts at dropped spindles JUST moved the pin. While this is nice, everything affects everything else. I think Sean's spindles, because they are designed with help from people in Detroit, may indeed work better than Mike's. Nothing against Mike, I have lots of his Dad's stuff. But my suspicion is that the Sean spindles are better, geometry wise, because more variables were considered. Sean has access to people in the industry that California people just can't get. That said, I haven't yet bought spindles from anyone. But I have a pair of '70 big pin drum spindles, and the 4 piston Galaxie calipers, waiting for a budget infusion. And I know SoT makes the brackets I need,........ LSG

I agree, it’s just that how the video is presented, it doesn’t make that clear. And as with the majority of things on the internet, it may well be taken as gospel and applied to all drop spindles. I appreciate that he came forward and put the information out there, as much as I appreciate Shaun and the information he contributes.

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CJM68GT390

· #15 · 5 mo ago

I did some suspension design work as a graduate student getting my M.S. in mechanical engineering in the early 70s. No question, each change affects everything else. If all that was done was move the spindle "up" to lower the car, the result would probably be less than desirable. However, today's computer programs make it possible for a small outfit like Sean to do stellar work. Many kudos to him for the quality work done by his team (and his willingness to listen!).

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GT289

· #16 · 5 mo ago

Shaun's effort is an indication of the lengths you need to go to in order to get to the answer of "better."
We worked on a taller spindle design for the 67-69 Camaro when there was about zero design and modeling
software available.

I don't know what Global is doing on Ford spindle design. (or if they're doing anything.....)
I will definitely tell you that Mike Maier is right that there can be too much tire, but I think we determined that was with stock/stock-ish spindles.
And the vintage Mustang has always been tire size limited in the front. The overwhelming take-away with that car was always that you never
could get enough front tire on it. (a situation that can be band-aided a bit by getting the front end as light as possible/moving the engine back)
Shaun's spindle looks to be very promising.

ex-Global West GM
1991-1995

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Nailbender

· #17 · 5 mo ago

Watching the MM video above and others I find it interesting what he considers a stock style fender. I believe old blue was running his fathers 2" flare fiberglass front fenders at the time, maybe more, and in the video above he makes it sound like you can run 275's with regular spindles and stock-ish fenders on a 65-66 and that is just not possible without a 20" wheel. I'm running 245/40/17's up front with negative 3 degrees camber and I don't think there is room for anything bigger. I assume most people don't want to cut up their cars for bigger tires and you can't do that up front without the tire/wheel going over the UCA and steering arm. MM seems to preach on the diminishing returns of moving the tire inboard and then you look at almost every modern car front or rear wheel drive and they all have a positive offset wheel. I realize the cars are designed for that offset. In a full on competition car like old blue the widest track available is going to be advantageous and the looks of the car secondary, not that it doesn't look cool for a race car! I guess what MM was trying to say was you don't need drop spindles to run big tires on your race or race type car with big flared fenders?
I'm always talking, texting, and sharing threads from VMF with much more experienced friends that I race with and appreciate their feedback, and that feedback has been important in my buying decisions.

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Westmus

· #18 · 5 mo ago

LSG said:
I wonder if we should view the above video as Mike saying we shouldn't buy HIS dropped spindles.

That's also going to be difficult since the video as I hear it, is an answer on why he do not sell drop spindles.

Mikes claim to fame is that he is the brain behind the suspension on several race winning cars and he as a driver have won races and several national championships in auto cross. He was the suspension "engineer" at MaierRacing before he left to start his own company.

GT289

· #19 · 5 mo ago (Edited)

Nailbender said:
Watching the MM video above and others I find it interesting what he considers a stock style fender. I believe old blue was running his fathers 2" flare fiberglass front fenders at the time, maybe more, and in the video above he makes it sound like you can run 275's with regular spindles and stock-ish fenders on a 65-66 and that is just not possible without a 20" wheel. I'm running 245/40/17's up front with negative 3 degrees camber and I don't think there is room for anything bigger. I assume most people don't want to cut up their cars for bigger tires and you can't do that up front without the tire/wheel going over the UCA and steering arm. MM seems to preach on the diminishing returns of moving the tire inboard and then you look at almost every modern car front or rear wheel drive and they all have a positive offset wheel. I realize the cars are designed for that offset. In a full on competition car like old blue the widest track available is going to be advantageous and the looks of the car secondary, not that it doesn't look cool for a race car! I guess what MM was trying to say was you don't need drop spindles to run big tires on your race or race type car with big flared fenders?
I'm always talking, texting, and sharing threads from VMF with much more experienced friends that I race with and appreciate their feedback, and that feedback has been important in my buying decisions.

Nobody needs drop spindles, until you get into other necessary spindle design changes, dropped spindles are mainly a "looks" thing.
Track width is an important criteria in vehicle stability. The fenders get in the way on an early Mustang.
Here's the late Eddie Paul's method of getting around that problem.....

ex-Global West GM
1991-1995

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jlangholzj

· #20 · 5 mo ago

GT289 said:
Shaun's effort is an indication of the lengths you need to go to in order to get to the answer of "better."
We worked on a taller spindle design for the 67-69 Camaro when there was about zero design and modeling
software available.

Every few times I open up RCVD, its always amazing to me how "old" the principles are. There's been some additional insight but the base ideas and concepts are nothing new. Any time I look at the information compiled by Doug Milliken or any of his contemporaries, its mind boggling how much extra work had to be done prior to widespread availability of CAD. You guys were nuts and we've got it easy now, especially with something as complex as suspension geometry.

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