Suspension Design - Take 2 - New and Improved and in 3D! My attempt at doing the impossible.

[@Beanpapac15]

Thank you for this series. It feels like nobody is really covering how to actually design suspension so this is very helpful.

[@ThrottleStopGarage]

Glad it was helpful!

[@The_R_Vid]

I wish I had something constructive to help advance you to the finish line. All I have is gratitude for the effort it's taken you to not only get this far, but also to share your journey with us! All hail the algorithm.

[@ThrottleStopGarage]

Thanks - I really hope this helps someone.

[@joshuaolson5265]

All hail the algorithm- sounds like Matt Brown from SuperfastMatt

[@ThrottleStopGarage]

​@joshuaolson5265 there is a lot of love for Super Fast Matt on this channel.

[@peterhenning7330]

Well done. I'm a motor bike guy and sadly none of this relates to my. But man,so interesting.

[@tezzrterry7485]

Some of it does, rake of the forks is castor, trail, and scrub etc are all on bikes, plus swingarm angle when seated on the bike.

[@ThrottleStopGarage]

Glad you enjoyed it

[@michaelfust9520]

Glad to see you back. Sorry to hear about your knees. Take care of them proper for recovery. Detailing is superb. One initial confusion for me was figuring out what direction was front of car on the side view.

[@ThrottleStopGarage]

Sorry about that. I hope which way was forward became more clear

[@michaelfust9520]

​@ThrottleStopGarage yes direction became clear after a bit

[@jaybauer6978]

I’m in awe of your dedication to your project. Thanks so much for sharing your learning process, and for helping me to decide to use a completely pre-engineered plug and play front suspension system on my 122. 😂

[@ThrottleStopGarage]

I wish I'd gone that route all those years ago. Saving money was not a good idea. I hope you find something that fits.

[@jesscneal]

Welcome back. Really interesting topic. I am a career CAD guy and have designed some RC car front suspension before. It's amazing how any little move on any dimension affects everything else. It's pretty involved to get it all dialed in and working right. Nice job on the model. That Lotus software looks pretty cool. I did see they discontinued it though. Your laptop is a museum piece :) Looking forward to more. Hope your knees are healing up nicely

[@ThrottleStopGarage]

Thanks - much appreciated. Knees are a bit of a mess - working through it. I've got over 60 iterations of the suspension in 3D (some chasing my tail for sure) not to mention at least that many in the 2D variants. Page after page of notes. I think it's going to be OK but I'm going to send it at this point or I'll never finish.

[@mceajc]

Oh wow! I am so glad I have stumbled across your channel! I'm trying to do very similar things - designing suspecsion fresh from scratch. I currently have a terribly complicated spreadsheet where I try and track points in 3-D (and am failing so far - but I think I can do it). I am nearly there on the set-up of the static suspension - then comes the hopefully easier part of generating performance plots afterwards. There are so few resources that go through the design, rather than either talking about the influence of various factors or analysing existing suspension. Having a way to play around, and see how each factor affects all the others is goingto provide so much insight on 1) choosing what factors to compromise on and 2) what parts to make adjustable to tune the characterisitics of the real thing. The list of possible input variables is so incredibly huge it is a daunting task to take on by yourself - knowing there are other people out there doing the same thing is encouraging! Keep on doing what you're doing, I will be watching avidly. Cheers! (Wonder where you got hold of a copy of Lotus Shark - isn't it expensive?)

[@ThrottleStopGarage]

You're very brave - carry on. I have very clear memories of when I think I got something right...then the next day found it was wrong. Over and over until I quit thinking about 2D stuff and moving points and went after the design hard. Hunting a property. Getting a little more right each time. It's been a journey.

[@codysmithmotorsports736]

Absolutely true that once you commit to one dimension the others start to fall into place. Since your last video I've begun building a tube chassis from scratch as my next racecar. For me that first dimension ended up being the steering rack position because after a bunch of measuring and math I kept coming up with poor situations if I started somewhere else. The rack position led to steering arm length and steering degrees available. In order to meet my needs that placed the tire, which set the spindle and ball joints which the set the pivots based on camber curve and roll center... It was an exhausting day of thinking. Not quite 2 months in and I'm fabricating the lower control arms now to be able to have it on all 4 wheels... maybe by the weekend. I also built mine around slugs in the mounts. Basically have +/- 1/2" on everything for tuning

[@ThrottleStopGarage]

It was an interesting experience. I know I've read it (I've even taught it) but when I've gone through a suspension the 40 or 50 times that I've done this and some things just fall out, it gave me a real sense that there are just a few critical decisions, the rest is then set. Next up for me will be the arms and uprights. Then we'll see how it all fits together. I hope to use the slugs I have for adjustment. These ideas are still floating right now.

[@Jallandhara]

Welcome back!

[@ThrottleStopGarage]

Thanks for watching.

[@glencoad737]

Excellent job and explanation looking forward to the engineering part.

[@ThrottleStopGarage]

Thanks. It'll be a few weeks at least until I get some of the design worked out. I've got a few ideas on how to make that UCA adjustment work that need a little more work.

[@MichielvanderMeulen]

watched two of your videos and haven't heard fables or untrue theories 👍

[@ThrottleStopGarage]

Whew...I'd be horrified if this was all wrong.

[@thunderbirdizations]

Can’t wait to watch this this weekend, Been looking forward to it, also great to see you’re doin well

[@ThrottleStopGarage]

Hope you enjoy it!

[@joell439]

🎉 - thank you 🙏. Very helpful discussion

[@ThrottleStopGarage]

This took a lot longer than I wanted - I'm just glad it is finally done.

[@cam3002]

If you want good book as a resource, I suggest Milliken & Milliken "Race Car Vehicle Dynamics". It is a difficult topic but you did a good job explaining it. This video was front centric, now it gets creative when taking into consideration what the rear is doing! On my project, I've made everything a little adjustable so I can fine tune it at the track. Outside of F1, I think it is considered desirable to have a little toe out on bump, meaning that in a turn, the unloaded tire should turn slightly more than the loaded tire. This is related to bump steer and Ackerman. Keep up the good work, nice to see you make progress.

[@ThrottleStopGarage]

Thanks. During this adventure, I read every vehicle dynamics book I could find. RCVD was one of the first. I finished the rear years ago - it's an IRS and everything back there is staying as is until I get it on the road and I can see how it all works.

[@alanmony1582]

Hey Craig, good to see you're still around! When I did my car (you know the one) I had just a little bit of knowledge. I knew that I didn't want bumpsteer and that placing the rack outer pivots on the line had a big effect on it. Parallelograms and all. So I modeled it on a sheet of plywood and cut out full size cardboard chassis components. Used pushpins to act as pivots and connected the upright with small nuts and bolts to simulate pivot points for suspension travel. Moved it up and down and said "that looks OK" . Started building on the car and realized I couldn't move the rack rearward enough to get any Akerman, "Oh, well" gotta accept that. I probably wound up with reverse Akerman 🙃. Whatever I wound up with seems to work well! When I turn the wheel clockwise the car goes to the right, perfect!!

[@ThrottleStopGarage]

Alan - glad you watched. I was racing with a guy this summer that built a crazy '69 Camero with an LS engine and a couple of turbos...and a mustang 2 front end. You know what - that car gets around a corner just fine. It convinced me that even with "sub-optimal" geometry, it wasn't garbage. That's around the time I stopped digging the hole.

[@bradmaas6875]

If you weren't wrong, you didn't learn anything. Good to see you're still with us.

[@ThrottleStopGarage]

100% - if you feel like you were kicked in the head by a horse...then you really learned something. LOL.

[@telecomwiz2004]

What a great job explaining this. You should explain a proper pushrod suspension design too!

[@ThrottleStopGarage]

Thanks - There are a lot of fun tricks that can be done with pushrods.

[@The_Performance_Laboratory]

Great explanations. Carroll Smith is great reference material. If you haven't already, look into the Gillespie and Milliken vehicle dynamics books too. Hope your knees get better soon.

[@ThrottleStopGarage]

Thanks - I have those in the library! Smith's book is brilliant as it is written as if he's sitting in the shop and chatting. There is an art to communicating these complex things that simply.

[@kathysarmcandy1992]

Having done alignments for 40 years, that looks legit. I guess allow for obvious camber and caster adjustments up the uppers. A standard set of figures for road use would look like +.5* camber, +3/4-1.5 caster. Possible much more caster for high speed stability. So allow if adjusting from the upper control arms, movement both at the front and rear via slots of shims. Toe in, about .10-.12". Then you've got steering arm lengths, so you can try and figure toe out on turns. That could be tricky. Unless you've already got fixed knuckle placement via the Corvette ones.

[@ThrottleStopGarage]

I've got a plan for the UCA adjustment but need to work it out a little more. I'm leaning toward slotted holes for adjustment.

[@storminnorman1932]

Thank you !! we have been waiting with sardine baited breath

[@ThrottleStopGarage]

Thanks - sorry for being so slow.

[@thunderbirdizations]

48:45 ❤

[@VacFink]

A company like QA1 suspension would be my goto for questions. They design tubular suspension upgrades for a number of cars and can seem like regular guys when I've talked to them about non-product questions. I spent an hour at a booth five or six years ago asking about modifications to existing hardware and getting good explanations on why that wouldn't and would work. I've learned in the past that presenting the problem before I ask for help gets me nowhere. Simply asking for help or a chance to ask a question on the phone is the foot in the door. After that complimenting university professors about publications are a clean way into favor for probing more informed minds. I love this clearly challenging approach. I'm sure those knees will recover from your jump into the abyss of suspension. Better the knees than your keister.

[@ThrottleStopGarage]

I had not thought of contacting them. I was contacting other suspension people and...well, I'm just a guy and I don't have a race team or a million dollars so crickets. No big deal. I couldn't read half of the articles I wanted to check out because the SAE has them behind paywalls! $40 for a paper and I'm not sure if it's even on topic.

[@joshuaolson5265]

Great job and it was cool to see Lotus Shark suspension analysis! I already trying to figure out how i can get a copy of the software for my project. (No videos yet but I'm going to put old 1954 Chevy Truck on a BMW first series suspension) You are a pioneer and I appreciate your determination with making your dream vehicle and not settling with the C4 geometry. Looking forward to seeing it mocked up in the next video!

[@ThrottleStopGarage]

Lotus Shark is great for this. I've tried three other packages and WinGEO was also very good. The problem is that you can't get this stuff because you need an ancient computer to run it.

[@AndrewVerran]

Suspension design is so hard. Years ago I read "Competition Car Suspension Design" by Alan Staniforth and my head near exploded. It's been 25 years and I still haven't read the last 10 pages (might do it now, lol). Loved the video, looking forward to the action next time out.

[@ThrottleStopGarage]

I've got his book - it's acually one of the better ones for readability. I probably made this much harder than it really needs to be - but it's really that complicated.

[@newagetemplar6100]

Ha ha ye ole rabbit hole of suspension geometry. 😳. I found your original content very helpful as it was more visual than the many numbers and figures explanations on YT . I ended up using my steering rack inner joints as a datum for the lower wishbone pick ups to eliminate bump steer and worked backwards around the roll centre to determine everything else. Of course that was fine until you find that your wheel offset determines scrub radius and disc position 😂. Then because mines a race car it has virtually zero droop on the front axle and only maybe 1 1/2 of compression camber gain becomes an issue. Round and round in circles many many times. 🤭 And I’ve not taken into the equation I’m going full pushrod suspension with full aero package with an adjustable bladed roll bar on the front and will be using a third element to compensate for the rear downforce created by the rear aerofoil and huge diffuser.😵‍💫wish mee luck Great helpful content for anyone Thank you 👍🏴󠁧󠁢󠁥󠁮󠁧󠁿

[@ThrottleStopGarage]

Wow. That sounds intense. Glad the videos have helped.

[@danehart2740]

I think you are going to have some really nice suspension when you are done. Having put a ton of cars in the air on a lift, there are some production cars out there with crazy camber and toe changes at full droop. I think you are holding yourself to a standard that is beyond what some auto manufacturers do. At the very least it will be way better than what the car came with.

[@ThrottleStopGarage]

Thanks - I appreciate the positive feedback. I do hope this all turns out and the suspension works.

[@kathysarmcandy1992]

Now that's I've slept on it. A few corrections. Final geometry will be fairly dependant on you tire specs. Particularly the aspect ratio and width. I would assume you're going for a fun street car. So a 60 series would be fine. Going to need some sidewall flex as the control arms move thru the arc. The shorter the sidewall of the tire, the more true to camber setting it will have to be or cornering traction will suffer. If you go say with a 225/70, most is forgiven. I would be tempted to hard model it next with a RC car from the hobby shop, which many already has adjustable bits. Traxxis, Tamiya, etc. But you can buy individual replacement suspension spares and piece it up, per CAD. Then you can jounce, squish and ponder. Also great for visualizing lateral acceleration to have physical body. Later.👍

[@ThrottleStopGarage]

That's for sure something I'm thinking about. Front tires are 225/45 r17. So less sidewall. This selection is based on current tire availability and future supply in a size that will work.

[@evgenysavelev837]

Yay.

[@keithwood4297]

I had a truck that had horrible bump steer, pot holes were terrifying!

[@ThrottleStopGarage]

Speed bumps are also an adventure!

[@AndyFromm]

Beyond my pay grade 😮

[@insAneTunA]

Same here,

[@ThrottleStopGarage]

Sorry - I tried.

[@AndyFromm]

@@ThrottleStopGarage don't be sorry, it's good stuff. I know where I'm coming back to if I'm doing custom suspension geometry on a project.

[@AndyFromm]

​@@ThrottleStopGarage Ackermann, I assume the oem just picks a happy spot to cover most the wheel bases? What happens when a vehicle is stretched into a limo? Tires scrub?

[@ThrottleStopGarage]

@@AndyFromm I really don't have any sense of this. For the car I autocross, it has a lot of Ackermann and at low speeds the inside tire scrubs across the ground. At speed it is fine (dynamics fixes the issue).

[@Low760]

24:55 i think about Lexus front suspension, the is300 first gen, the soarer/supra mk4, ls400 on. They run a fair bit of angle for the top arm for anti dive. Bmw don't use double a arms so you can't check with them but Lexus do a good job for handling i think. Great video. Watched it when i normally listen to videos. My 122 is staying stock, but I've got an mg td to build for my wife and keeping the stock mg cross member is my limit but the top arm being upgraded is a great option given an engine upgrade to a Mazda unit.

[@ThrottleStopGarage]

It's interesting how some of the things in the 2D model that I though were important just weren't in 3D. I almost never checked the roll centre - when done, it was a little lower than 60 mm but right on. It still makes my head hurt.

[@bonovoxel7527]

Hey! Yup I can confirm some contents are confusing on that you first set the lower inboard pickup point. It's as you said instead: RCH first, then derive that virtual arm. Because "virtual" is another thing nobody says. It's the actual height of the triangle. It's all hidden in plans sight like the Holy Grail in Langued'oc :DDD (...that thing got me confused bc it points you towards making the lower arm as flush as possible with the chassis but this just has no direct relation with what you're doing it has with rollcenter instead!! And I had to get back looking close at a lot of vehicles like my proto (it's a crosskart) before convincing myself that it's fair to have instant centers above the chassis ground, and that's where it was the missing ground clearance I was looking for, in the end.)

[@ThrottleStopGarage]

I think there needs to be a support group for anyone that has survived designing their own suspension. I went around in circles with software until I worked out the RCH cheat...then the FVSA length sent me over the edge...then I worked that out. If this helps a single person, I'd be very happy.

[@bartylobethal8089]

This is all about the spatial relationships between points. That should scale. Build yourself a cycle cart and trial your design. Adjustments will be relatively inexpensive. When you've settled on a design, scale it up and make the 'real' thing.

[@ThrottleStopGarage]

Once I've got it in Fusion, I'll 3d print a model and see how it works.

[@CeeCeeOy]

Hey, nice video. Lot of information. I cant help to compare those tto C4 (you know why) and our chats about it. Things I sad, like position of the rack been off.. Hope you get your mojjo back on full tilt.

[@ThrottleStopGarage]

I'm starting to see the light. I'll finish up the suspension design over the holidays and see what happens when I build it.

[@austinlambert3994]

You mentioned you picked 20mm for you scrub radius and didn't know quite why. Here is a quick answer based on my knowledge The tire flexes as you apply a lateral load and that will bring your tire center towards the inside of the turn. Generally your trying to line the steering axis line with the center of the contact patch under load. So wherever you got the 20mm from was someones guess that the tire would flex over 20mm under load and designed his suspension around it. There are labs that will tell you these characteristics. The stiffer the tire and the smaller the sidewall will decrease flex.

[@ThrottleStopGarage]

True - without that tire model, the 20 mm is a bit of a guess. The information is pretty vague - there is also a moment created by the offset to the contact patch centre and a few other considerations. Most things I've read were a little vague about the value - something between 10 and 40 but not more or less is what it summed up to.

[@austinlambert3994]

@ TBH, 20mm sounds like a lot. I’m in the desert racing world where that number can be over 2 inches. There are some wild videos of the tires bouncing back and forth through corners. You can see F1 tires do something similar in slow mo as they unload mid corner and touch a curb and while super noticeable, I would guess it’s closer to 10-15 mill. It’s not a huge deal if you get it slightly off. That moment you mentioned will cause the tire to skid just a little and understeer which is usually preferable. It simulates just a touch of front braking which hurts lap times but would be unimportant for a road car.

[@georgeplevritis5190]

Nice work, I have a few comments its too much for one post so I’ll break it up, first I don’t remember if you are making your own spindles now or just using the corvette ones but just remember mechanical trail the hub doesn’t have to be centered in the knuckle.

[@georgeplevritis5190]

You mentioned scrub I think 20mm and that fine for a street car but tires are a big part of deciding scrub, remember you have effective scrub and actual scrub, in one of your past videos you talked about the vett scrub being like 40-50 (I don’t remember the exact number) and how horrible that is, I struggled with this also some years back until I learned why the that school of thought was used, 40-50 scrub on open wheel race cars is not uncommon, the high static negative cambers plus wide soft compound tire and slip angles required more scrub to keep the contact patch closer to ideal, anyways like you I wouldn’t run that much especially because of the rack and pinion your using, wide tires and high scrub would punish that rack so I wouldn’t run try and keep the road force torque to a minimum. 20-25 is good imo.

[@georgeplevritis5190]

Ackermann for short tracks autocross type of racing I would run as close to 100% as possible.

[@ThrottleStopGarage]

Making my own everything. C4 stuff will be up for sale at some point.

[@ThrottleStopGarage]

That was my line of thinking. The C4 was more like 75 mm or something. I did read a bunch about the nature of scrub and the variables, most of what I could read came down to having it not cross from positive to negative and not having too much.

[@hoffbug]

Was wondering how the project was coming along. Sorry to hear about the knees... That makes working without a lift tougher.

[@ThrottleStopGarage]

Slowly on all fronts...meniscus tears and MCL damage is not making this easy.

[@dan1906]

Good to see you back. I'm curious what tire size and wheel spec you're running? I assume you have that worked out since you modeled the tire height and centerline.

[@ThrottleStopGarage]

It's nice to be back! 225 45 R17's are the size for the fronts. Wheels are 45 mm offset (packaging ball joints and brakes mostly).

[@leemuscarella2728]

So will you be able to still use the C4 control arms if you adjusted the points? Great Chanel.

[@ThrottleStopGarage]

No, I'm only able to save the custom bushings i designed for the C4. Nothing else will work.

[@mitchellsnider4198]

Easier way in my opinion to visualize the forces for anti-dive (I think this is from Milliken): draw an imaginary slot that the axle travels in, direction of the slot being the instantaneous direction of the contact patch (perpendicular to the line to the IC) Upper and lower arms level means the slot is fully vertical. The full horizontal braking force of that tire goes through the walls of the slot, and the spring is the only force in the direction of the slot so it’s left with the job of counteracting the pitch moment (pitch torque). If you change the angle of the arms, the slot (which represents wheel travel) is now inclined such that the axle moving in the slot direction is perpendicular to the contact patch/IC connecting line. You tip the slot back and your reaction force from the wall of the slot points slightly up, and the spring now needs to handle some of the braking force (this is the jacking you were talking about) and also the pitch moment: Pro dive. The opposite is anti-dive, where the slot is tipped forward, or the contact patch technically is moving forward. This is why motorcycle forks dive so much: high Center of gravity and also the whole wheel assembly travels in the pro-dive direction at the angle of the fork rake. Perfect storm for bottoming out the front suspension.

[@ThrottleStopGarage]

I'll have to go back and check RCVD to find that - this is a great explanation. What really unlocked it for me was that it's static based on the fixed points and I was so stuck in the FV that my brain didn't grasp it until I stoped watching explanations, grabbed a sheet of paper and did a force diagram. Bingo - simple...and then you feel stupid for not having the light flick on. Learning.

[@mitchellsnider4198]

another one that worked for me though it’d be less transferable to others is imagining an equivalent 4-link suspension from the side, since the instant centers and jacking moments seem more intuitive when you can “see all the circles”. This is probably because I’m a CSWP/mech Eng but when I did this for my transaxle Jaguar IRS design I had a much better time using a combination of 2D and 3D sketches and immediately modelling parts within a mess of 3D scans than sticking in the land of 2x2D. I had some TIGHT brake/body clearances I was working with on top of managing all the curves so it was essential that I get to 3D and start waving that corner around asap so I could come up with a strong design that actually clears. I’m using the ol’ laser sheet metal origami trick to make everything. You don’t seem as backed into a corner as me in that respect but if you do get stuck feel free to reach out on fb/instagram (this is my real name) and I can show you what I did. Pretty sure you’re local to me too but obviously no need to discuss locations publicly in the comments here.

[@ThrottleStopGarage]

@@mitchellsnider4198 Thanks - I do wish I'd tried to do this in 3D from the start. It probably would have taken less time and would have ended up in the same place. Getting clearances and packaging sorted out was/is a challenge. I'm also trying to use as many OTS parts for brakes and hubs etc as I can. I'll fully design uprights and arms - no problem - but I'd like to avoid having to design the rest.

[@mitchellsnider4198]

@@ThrottleStopGarage bingo, steal the engineering wherever you’ve got consumables, seals, and precision: brakes, engines/transmissions, axles/CVs, glass, dampers. I’ve retrofitted Honda Fit brakes on my Kei truck, and my XJS is getting Audi A6 brakes (had them lying around and they just barely clear 17s which is perfect). Looks like you’re generally following that same philosophy too. You kinda broke that rule with your carbon body but it looks like you had fun, learned a lot, and absolutely earned some respect, from me at least!

[@ThrottleStopGarage]

@@mitchellsnider4198 The carbon body did sort of get away on me. I really just wanted parts that won't rust - then it got out of control and well...there is still a roof that needs to be lighter at some point.

[@ChuckThree]

He’s back! I hope you haven’t slowed down on the build and instead have a backlog of footage to edit and publish during the winter months

[@ThrottleStopGarage]

I've slowed down a bit...but hope to regain speed over the winter. Thanks for watching.

[@Metal2Mesh]

it would great if you could 3D scan the components, CAD them and then you could move them around in a virtual space and simulate. But yeah time and money. The scanning is the easy part, its the CAD that would take the most time.

[@ThrottleStopGarage]

I'm working on a video like this. I needed the scans to get an accurate version of the steering rack.

[@filepz629]

❤️‍🔥🫂❤️‍🔥

[@arrindaley3714]

My concern is you might be under valuing the correct ackermann, your'e correct in F1 run very different ackermann but they don't do any real tight maneuvering and have very different priorities, whereas in a road car at slow carpark speeds (where load on each tyre is more equal) you'll have the wheels fighting each other. Getting ackermann correct for your design which looks like you're putting the steering rack forward of the steering axis(presumably to avoid part of the engine?) is likely be difficult as the end of the steering arm would need to move out towards the tyre and disk rotor where there's not as much room (this is one reason most steering racks are behind the steering axis). It didn't transfer to you're 3D model but when you transferred the suspension pivot heights to the side view on the video you transferred the ball joint height and not the inner A arm height (bottom wouldn't matter but the top should be lower).

[@ThrottleStopGarage]

Good point. I will take another look at it.

[@tiitsaul9036]

I agree, my ex gf had a lot of bum steer and it was difficult to handle.

[@ThrottleStopGarage]

LOL. Staying clear of this one.

[@lesgaal4017]

My only advice to you as retired engineer is before the weld or build your suspension set up is to build a mock up system that's adjustable. Through out my years in the industry ive always gone back to this basic system once knowing my chassis dimensions and total wet weight.

[@ThrottleStopGarage]

That's excellent advice - thank you. I will do that for sure.

[@bewernia]

I think for a daily driver Bump Steer is the absolute worst thing in the world. I had a small truck that suffered from bump steer and it took nearly all the joy out of driving it.

[@ThrottleStopGarage]

100% agree. It's a very weird feeling in a vehicle.

[@pitt42075]

I like your series but “paralysis by analysis” seems to be the phrase that comes to mind. Put some tried and true suspension under it. You’ve built a carbon fiber Volvo Amazon!! - built it, drive it.

[@ThrottleStopGarage]

There were points where I struggled - not paralysed by any means. At this point, I've designed a suspension for the car. This all started by trying to graft something into the car and it was never right. I'm building this one and we'll see how it goes. I think it's going to be just fine.

[@ultra4suzukisamurai679]

Any one that’s owned an early lifted ford ranger knows that most of this really doesn’t matter. lol.

[@ThrottleStopGarage]

Until that first corner when you flip. LOL.

[@ultra4suzukisamurai679]

@ the old TTB and twin I beam fords do everything wrong. I had one modified for off road, had at least 3” of toe change through the travel. Horrible. Drove great in the dirt though. I currently have a Suzuki samurai based race car. 14” of front travel. I spent an incredible amount of time designing it to have good geometry and minimize bump steer. Great channel!

[@ThrottleStopGarage]

@@ultra4suzukisamurai679 We had a few F150's back in the day...tire wear was an issue. 14" of travel - that's hero stuff.

[@insAneTunA]

Complicated!

[@ThrottleStopGarage]

More than I thought!

[@JackieKraft]

Thought you fell off the planet man… You may be overthinking this, Can’t you just grab a rack and pinion off a mustang 2 or something?

[@ThrottleStopGarage]

Overthinking is for sure what has been going on. No question. The M2 rack is just a little longer than the BMW and generally has a slower ratio. The BMW unit is already in the garage as I stop digging this hole and start building.

[@tezzrterry7485]

@@ThrottleStopGarage Speedway sedan guys, and other race car builders, seem to use a short rack, with long arms, so that the pivot points are way inside the suspension pivot points.

[@ThrottleStopGarage]

@@tezzrterry7485 That's what the car comes with - the issue is that the longer LCA starts to restrict engin bay space and getting short powered racks is difficult. I've got a shorter power rack from Woodward and with the external ram, it also doesn't package nicely. I think these race cars have engines behind the rack and I can't fit the engine that way.