Random thoughts about FC suspension design.
#1
The Firestarter
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So i am sitting here thinking about my next plan of action as far as doing up a FC chassy starting from the ground up. And i wondered about the suspension design of the FC and how it uses a LCA Front and a swing arm attached to the sub-frame in the rear. While i had no complaints about how my last FC preformed once the new bushings and DTSS eliminator was installed I never thought about how i could make it better over past coilovers.
So here are my questions, Double wish bone /multi-link should be a "superior" design as it allows for better control of each linkage & vertical movement correct? In comparison with the McPherson hub design type that the FC has, would it safe to assume that the car does experience various unwanted and unstable camber changes and side travel during vertical movement? So would it be plausible for myself to convert and engineer a Multi-link Double wish bone suspension design front and rear fitted for the FC3S (for road racing applications) to combat unwanted changes in the geometry of the suspension that i may not be aware of? or Perhaps that the the current design doesn't suffer these issues and maybe building my own LCA and Swing arms made of stronger & lighter materials may suffice? The goal of this thread is explore various applications for road racing / time attack in regards to HUB/ARM/LINK/ in the FC3S and how to address issues that we may not be aware of that exists. (This could apply to your own street car)
Thoughts and opinions, speculations are encouraged! Keep senseless arguments at a minimum please.
-Josh
So here are my questions, Double wish bone /multi-link should be a "superior" design as it allows for better control of each linkage & vertical movement correct? In comparison with the McPherson hub design type that the FC has, would it safe to assume that the car does experience various unwanted and unstable camber changes and side travel during vertical movement? So would it be plausible for myself to convert and engineer a Multi-link Double wish bone suspension design front and rear fitted for the FC3S (for road racing applications) to combat unwanted changes in the geometry of the suspension that i may not be aware of? or Perhaps that the the current design doesn't suffer these issues and maybe building my own LCA and Swing arms made of stronger & lighter materials may suffice? The goal of this thread is explore various applications for road racing / time attack in regards to HUB/ARM/LINK/ in the FC3S and how to address issues that we may not be aware of that exists. (This could apply to your own street car)
Thoughts and opinions, speculations are encouraged! Keep senseless arguments at a minimum please.
-Josh
#2
If you want to then go for it. Most people find it more cost effective to just buy an FD...or a Miata. The stock control arms are aluminum so theres not much room for improvement there. I wouldn't underestimate struts in general, some of the fastest time attack cars in the world have struts like EVOs, STi's, BMWs, Porsches.
#3
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I am not underestimating strut design, and yes i understand that there are various performance cars that utilize this type of suspension. I for one have no issues with the current design for the FC as of yet. I am just bringing this idea up as a discussion, rather than actually considering producing parts for an actual conversion.
#4
So here are my questions, Double wish bone /multi-link should be a "superior" design as it allows for better control of each linkage & vertical movement correct? In comparison with the McPherson hub design type that the FC has, would it safe to assume that the car does experience various unwanted and unstable camber changes and side travel during vertical movement? So would it be plausible for myself to convert and engineer a Multi-link Double wish bone suspension design front and rear fitted for the FC3S (for road racing applications) to combat unwanted changes in the geometry of the suspension that i may not be aware of? or Perhaps that the the current design doesn't suffer these issues and maybe building my own LCA and Swing arms made of stronger & lighter materials may suffice? The goal of this thread is explore various applications for road racing / time attack in regards to HUB/ARM/LINK/ in the FC3S and how to address issues that we may not be aware of that exists. (This could apply to your own street car)
Is it feasible? If you're planning to put together a "double-wishbone kit", it would be very hard to sell, simply because of the R&D involved -> high prices.
The design would be cool though. If I were you and were designing a similar suspension, I would take it a step further and move the shocks/springs inboard, creating a sort of cantilever/pushrod system, eliminating a good chunk of unsprung weight.
If working with factory designs, creating lighter parts (LCA's, trailing arms) will usually result in less unsprung weight, but the costs involved are varied.
That's all I can type for now, midterms hurt.
#5
Im not a real fan of the suspension design myself.
i think a good basis right now would be to copy one of the time attack cars..
for example, the Super Now FC is pretty dam fast right now.. check out some of their suspension setups. Changed lca pivot area
![](http://www.supernow.co.jp/shop/img/20061005235436.jpg)
![](http://dp04094399.lolipop.jp/diary/img/20040612-3.jpg)
Some trick stuff with them
http://www.supernow.co.jp/diary/diar...ead&y=2004&m=6
![](http://dp04094399.lolipop.jp/diary/img/20090201-3.jpg)
i think a good basis right now would be to copy one of the time attack cars..
for example, the Super Now FC is pretty dam fast right now.. check out some of their suspension setups. Changed lca pivot area
![](http://www.supernow.co.jp/shop/img/20061005235436.jpg)
![](http://dp04094399.lolipop.jp/diary/img/20040612-3.jpg)
Some trick stuff with them
http://www.supernow.co.jp/diary/diar...ead&y=2004&m=6
![](http://dp04094399.lolipop.jp/diary/img/20090201-3.jpg)
![](http://dp04094399.lolipop.jp/diary/img/20061219-3.jpg)
#9
You mentioned speculation was welcome...
Redesigning the FC to have a radically different suspension system is way too much work, for too little gain, when you consider all other variables you can improve on that are easy to do, including driver training...
A good coil-over setup with the right driver will make a world of difference, though.
Redesigning the FC to have a radically different suspension system is way too much work, for too little gain, when you consider all other variables you can improve on that are easy to do, including driver training...
A good coil-over setup with the right driver will make a world of difference, though.
#10
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I've seen front SLA conversions for Mustangs, so its been done.
http://www.griggsracing.com/product_...roducts_id=458
However, unless you are an engineer with access to alot of modeling and manufacturing tools, its going to cost you a fortune and you may as well just buy a FD. I only say this because, while certainly it would be relatively easy to rig up something that looks like it might work, in reality you could easily run into binding or other unintended geometry issues without a proper working model of the system and end up with a slow and ill handling car, but with a mad cool custom suspension.
There are indeed some fast cars with front struts, but they are fast in spite of them. There is no question that a SLA setup is superior in basically every aspect other than cost.
http://www.griggsracing.com/product_...roducts_id=458
However, unless you are an engineer with access to alot of modeling and manufacturing tools, its going to cost you a fortune and you may as well just buy a FD. I only say this because, while certainly it would be relatively easy to rig up something that looks like it might work, in reality you could easily run into binding or other unintended geometry issues without a proper working model of the system and end up with a slow and ill handling car, but with a mad cool custom suspension.
There are indeed some fast cars with front struts, but they are fast in spite of them. There is no question that a SLA setup is superior in basically every aspect other than cost.
#12
I've seen front SLA conversions for Mustangs, so its been done.
http://www.griggsracing.com/product_...roducts_id=458
However, unless you are an engineer with access to alot of modeling and manufacturing tools, its going to cost you a fortune and you may as well just buy a FD. I only say this because, while certainly it would be relatively easy to rig up something that looks like it might work, in reality you could easily run into binding or other unintended geometry issues without a proper working model of the system and end up with a slow and ill handling car, but with a mad cool custom suspension.
There are indeed some fast cars with front struts, but they are fast in spite of them. There is no question that a SLA setup is superior in basically every aspect other than cost.
http://www.griggsracing.com/product_...roducts_id=458
However, unless you are an engineer with access to alot of modeling and manufacturing tools, its going to cost you a fortune and you may as well just buy a FD. I only say this because, while certainly it would be relatively easy to rig up something that looks like it might work, in reality you could easily run into binding or other unintended geometry issues without a proper working model of the system and end up with a slow and ill handling car, but with a mad cool custom suspension.
There are indeed some fast cars with front struts, but they are fast in spite of them. There is no question that a SLA setup is superior in basically every aspect other than cost.
it would be very difficult to make your own suspension without significant skills and resources
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Non of those parts are anything new. I can call AWR and get all those parts at my house tommorrow. Better parts at that as AWR camber links allow independant adjustment of the rear arms.
All you did was post pics of parts that allow adjustment of the same suspension design that you claim you're not a fan of. Adding those parts doesn't change the design in the least, all they do is allow more adjustment of the same design.
As far as racing goes, driver has more to do with it than anything. A few years ago when I was active in auto-x, the FTD was generally a 13B P-Port in an FB. Yes FB as in solid axle was getting the FTD's going up against corvettes, porsches, FC's, FD, with 2x & 3x the hp and beating the snot out of them.
#15
I ran across this suspension buildup thread awhile back:
http://www.ziptied.com/forums/index....2422#msg132422
The OP said he removed the rear sway bar to improve handling, going as far as to grind off it's mounting point on the suspension. Though he never goes into any detail as to what it really does, can anyone ratify or refute his claims?
http://www.ziptied.com/forums/index....2422#msg132422
The OP said he removed the rear sway bar to improve handling, going as far as to grind off it's mounting point on the suspension. Though he never goes into any detail as to what it really does, can anyone ratify or refute his claims?
#16
I ran across this suspension buildup thread awhile back:
http://www.ziptied.com/forums/index....2422#msg132422
The OP said he removed the rear sway bar to improve handling, going as far as to grind off it's mounting point on the suspension. Though he never goes into any detail as to what it really does, can anyone ratify or refute his claims?
http://www.ziptied.com/forums/index....2422#msg132422
The OP said he removed the rear sway bar to improve handling, going as far as to grind off it's mounting point on the suspension. Though he never goes into any detail as to what it really does, can anyone ratify or refute his claims?
that's not really what this threads about
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#17
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Non of those parts are anything new. I can call AWR and get all those parts at my house tommorrow. Better parts at that as AWR camber links allow independant adjustment of the rear arms.
All you did was post pics of parts that allow adjustment of the same suspension design that you claim you're not a fan of. Adding those parts doesn't change the design in the least, all they do is allow more adjustment of the same design.
As far as racing goes, driver has more to do with it than anything. A few years ago when I was active in auto-x, the FTD was generally a 13B P-Port in an FB. Yes FB as in solid axle was getting the FTD's going up against corvettes, porsches, FC's, FD, with 2x & 3x the hp and beating the snot out of them.
I am designing that same setup for a friends, 70 chevelle right now. With that said some of theses muscle car guys a re pulling over a lateral G with tubular control arms and solid axles.
#19
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Non of those parts are anything new. I can call AWR and get all those parts at my house tommorrow. Better parts at that as AWR camber links allow independant adjustment of the rear arms.
All you did was post pics of parts that allow adjustment of the same suspension design that you claim you're not a fan of. Adding those parts doesn't change the design in the least, all they do is allow more adjustment of the same design.
As far as racing goes, driver has more to do with it than anything. A few years ago when I was active in auto-x, the FTD was generally a 13B P-Port in an FB. Yes FB as in solid axle was getting the FTD's going up against corvettes, porsches, FC's, FD, with 2x & 3x the hp and beating the snot out of them.
I dunno why people always gotta try to out-prove each other "oh you can get the AWR parts been out forever" who cares? i was just posting what they where running which works really well for them.
#20
If you want an SLA suspension, then buy an FD. The Mustang SLA conversions are $3500+ and that is the cheapest one. I tihnk it woudl be too cost prohibitive to do in an FC.
The R&D would be better served in making a new front K member with improved geometry.
You can get the car pretty dialed in with the OEM suspension architecture. There really is no need to reinvent the wheel on this one, unless cost is no object.
The R&D would be better served in making a new front K member with improved geometry.
You can get the car pretty dialed in with the OEM suspension architecture. There really is no need to reinvent the wheel on this one, unless cost is no object.
#21
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You mentioned speculation was welcome...
Redesigning the FC to have a radically different suspension system is way too much work, for too little gain, when you consider all other variables you can improve on that are easy to do, including driver training...
A good coil-over setup with the right driver will make a world of difference, though.
Redesigning the FC to have a radically different suspension system is way too much work, for too little gain, when you consider all other variables you can improve on that are easy to do, including driver training...
A good coil-over setup with the right driver will make a world of difference, though.
Hypertek, thnx for the pics
hmmm a Roll center correction ball joints.....interesting you mentioned that KhanArtisT because several years ago i was on a mission to find roll center correction ball joints but ended up using AWR roll center blocks which did nothing for me as well. Good thing i am a little less ignorant vs then..(well i hope rofl)
Hecubus84, eliminating Rear sway sounds kinda sketchy, although i can see how the driver feels like its more responsive. Possibly something worth researching.
I wish i could do thermal load graphs to show how the FC suspension stresses. It would be nice to actually see where energy & load travel through the body of the car and how it dissipates.
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The rear suspension is more solid, cancels out the DTSS steer, changes the front pick up point on the lca. I think its worth mentioning..
I dunno why people always gotta try to out-prove each other "oh you can get the AWR parts been out forever" who cares? i was just posting what they where running which works really well for them.
I dunno why people always gotta try to out-prove each other "oh you can get the AWR parts been out forever" who cares? i was just posting what they where running which works really well for them.
Now, to stay on topic-
Re-Engineering a suspension is not an easy feat. If you want double A-arms, think about all the geometry that's involved and all the added mounting points and parts. Is it better, yes - but by how much? Decent questions to ask when trying to gauge whether something like this is worth the rewards would be
Whats the highest Lateral G that an FD can attain?
Whats the highest Lateral G that an FC can attain using the same size/brand/model tires that the FD got? (using FC/FD as the power, weight and ditribution are about the same)
Is that difference worth all the work and coin? Probably not considering the lateral g's that an R-comp equipped FC can get.
Maybe this is your little toy experiment where the cost vs benefits have absolutely nothing to do with it and you just want to see if you can do it. If that's the case, by all means, go for it. But if this is for a street/mild track car where time and cost are a factor, I don't see the gains being worth the expense, mainly becuase the expense will be so high.
#24
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If you want an SLA suspension, then buy an FD. The Mustang SLA conversions are $3500+ and that is the cheapest one. I tihnk it woudl be too cost prohibitive to do in an FC.
The R&D would be better served in making a new front K member with improved geometry.
You can get the car pretty dialed in with the OEM suspension architecture. There really is no need to reinvent the wheel on this one.
The R&D would be better served in making a new front K member with improved geometry.
You can get the car pretty dialed in with the OEM suspension architecture. There really is no need to reinvent the wheel on this one.
The Front K member does sound like it has been neglected, but i am just making assumptions. Thnx for the direction change.
and i agree with you that the OEM suspension can be dialed in very well.
For anyone If you didnt read my original post, this thread is to EXPLORE THE APPLICATIONS FOR FC3S.
So what have we gathered thus far;
1. Cost for R&D and Production = Fail ...that was an obvious reasoning to begin with.
2. Large gains vs minimal gains is only reasonably debatable when there's data to compare
3. OEM design is relatively sufficient
4. Center of Gravity and Roll center IS still an issue that has not been addressed.
5. Rear sway bar elimination changes the tire ground contact (good or bad is debatable)
6. Supernow & AWR make products to allow for a range of adjustments that the OEM design does not allow.
7. DTSS is fail (also debatable)
8. Cantilever system may be favored over SLA (debatable)
9. Unwanted changes in tire movement and how to prevent them still needs to be discussed.
10. Ideas in improving the design structure of the subframe and K member.
Moar XD
#25
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You're missing the point, you're not changing the actual design of the suspension in the least. All you're doing is adding adjustability. It's not about "out proving" someone, it's about making concise, helpful, on topic posts which your's was not. Your post was, look at the shiny purple JDM parts that a japanese tuner is using.
Now, to stay on topic-
Re-Engineering a suspension is not an easy feat. If you want double A-arms, think about all the geometry that's involved and all the added mounting points and parts. Is it better, yes - but by how much? Decent questions to ask when trying to gauge whether something like this is worth the rewards would be
Whats the highest Lateral G that an FD can attain?
Whats the highest Lateral G that an FC can attain using the same size/brand/model tires that the FD got? (using FC/FD as the power, weight and ditribution are about the same)
Is that difference worth all the work and coin? Probably not considering the lateral g's that an R-comp equipped FC can get.
Maybe this is your little toy experiment where the cost vs benefits have absolutely nothing to do with it and you just want to see if you can do it. If that's the case, by all means, go for it. But if this is for a street/mild track car where time and cost are a factor, I don't see the gains being worth the expense, mainly becuase the expense will be so high.
Now, to stay on topic-
Re-Engineering a suspension is not an easy feat. If you want double A-arms, think about all the geometry that's involved and all the added mounting points and parts. Is it better, yes - but by how much? Decent questions to ask when trying to gauge whether something like this is worth the rewards would be
Whats the highest Lateral G that an FD can attain?
Whats the highest Lateral G that an FC can attain using the same size/brand/model tires that the FD got? (using FC/FD as the power, weight and ditribution are about the same)
Is that difference worth all the work and coin? Probably not considering the lateral g's that an R-comp equipped FC can get.
Maybe this is your little toy experiment where the cost vs benefits have absolutely nothing to do with it and you just want to see if you can do it. If that's the case, by all means, go for it. But if this is for a street/mild track car where time and cost are a factor, I don't see the gains being worth the expense, mainly becuase the expense will be so high.