F1 cars are a whole different animal. For starters, I don't think it's feasible for us to use suspension arms as long as they are on F1 cars. Secondly F1 cars actually have a horrible coefficient of drag. (IIRC above 0.45) For F1 cars it doesn't matter though because they make up for it with ungodly amounts of horsepower and grip they can carry through corners.
Downward force on the contact patch, be it aerodynamic or vehicle mass, is going to increase the tire's adhesion to the road surface. Where mass becomes the enemy is anytime you try to accelerate or decelerate it. In a corner you are changing the direction of the mass of the vehicle, resulting in a lateral force. The more mass or the tighter the turn, the more lateral force is generated until it overcomes the adhesion of the tires.
Here's a good answer to the question of weight and downforce.
"Difference Between Weight and Downforce"
"You may be wondering why, if aerodynamic downforce can increase cornering speed, does a lighter car corner faster? Why is vertical load provided by aerodynamics different than vertical load provided by weight?..."
Downward force on the contact patch, be it aerodynamic or vehicle mass, is going to increase the tire's adhesion to the road surface. Where mass becomes the enemy is anytime you try to accelerate or decelerate it. In a corner you are changing the direction of the mass of the vehicle, resulting in a lateral force. The more mass or the tighter the turn, the more lateral force is generated until it overcomes the adhesion of the tires.
Weight is the result of mass. Weight is not the same as downforce.
And the point I was making is that the plot of normal force vs. maximum lateral force of a tire has the steepest slope at lowest normal force. The less weight there is on a tire, the higher the lateral g it can generate.
Is anything else I've said you'd like to take out of context to argue about?
So nobody things the geometry of the suspension could be improved with the engine sitting where it does now?
Of course it can.
Gordon Murray said "The automotive problem is fundamentally one of packaging". Once you come up with a design that does what you want without any of the required components occupying the same space, the rest is just a matter of fabrication.
I wish that guy Hank from PA with the 383 fiero was still around. He completely redesigned his front and rear suspension. It was pretty trick from what I can remember from like 10 years ago, or however long it was.
And the point I was making is that the plot of normal force vs. maximum lateral force of a tire has the steepest slope at lowest normal force. The less weight there is on a tire, the higher the lateral g it can generate.
Is anything else I've said you'd like to take out of context to argue about?
So this being said, my tires with the most grip will be on unweighted side of the car as I make a turn?
------------------ yellow 88 GT, not stock white 88 notchie, 4 banger
in answer to why Formula one tires look like they do :they are forced to use spec tires by the rules of F1 .they are not the tires they would be using if they could run whatever they wanted to .
I wish that guy Hank from PA with the 383 fiero was still around. He completely redesigned his front and rear suspension. It was pretty trick from what I can remember from like 10 years ago, or however long it was.
Are there any pictures of that in existance? At least that may be interesting to look at.
So this being said, my tires with the most grip will be on unweighted side of the car as I make a turn?
Grip is the ratio of maximum lateral force to normal force (textbook definition). If you have 1000# normal force on your outside tire and 500# on your inside tire, your outside tire might have 0.9 grip, while your inside tire might have 1.1 grip. That means the outside tire can generate 900# of lateral force and the inside can generate 550. The total lateral force you have available to turn that end of the car is 1450#. Since that end of the car weighs 1500#, it can corner at 0.96g (= 1450/1500).
If you add 4,000# of aerodynamic force into the equation, equally distributed, then you'd have 3000# on the outside tire and 2500 on the inside tire. That might be a grip of 0.70 on the outside and 0.75 on the inside. Which would give 3975# of lateral force and a cornering acceleration of 2.65g (=3975/1500).
All numbers are pulled directly out of my @$$.
[This message has been edited by Will (edited 08-13-2011).]
Update: I'm in the midst of drafting up electronic drawings for the '88 front suspension, similar to the rears I've posted. Once complete, I'll post them here. This should enable a more comprehensive analysis of the effects of various changes.
Update: I'm in the midst of drafting up electronic drawings for the '88 front suspension, similar to the rears I've posted. Once complete, I'll post them here. This should enable a more comprehensive analysis of the effects of various changes.
Sorry if you have said alreardy but I have to ask anyway. Do you get your info from a suspension system out of your car or from technical data?
Do you get your info from a suspension system out of your car or from technical data?
For the rear, I used a combination of:
1. some of the cradle, ride height, and alignment dimensions from the service manual; 2. some additional frame alignment data from a tech service provided to collision centers; 3. the car's center of gravity height from Road & Track; and 4. the rest was by spending 300 hours measuring and drawing the parts from my project car.
I'm using the same approach to draw the front suspension, hopefully it will take less time.
1. some of the cradle, ride height, and alignment dimensions from the service manual; 2. some additional frame alignment data from a tech service provided to collision centers; 3. the car's center of gravity height from Road & Track; and 4. the rest was by spending 300 hours measuring and drawing the parts from my project car.
I'm using the same approach to draw the front suspension, hopefully it will take less time.
Why is that? I have to say I'm not familiar with that forum. (the data may be too technical, but it's worth trying)
they're engineers, so they'll ask you what you are trying to achieve and what you think is wrong with the current design. you'll get a general description of the direction you might want to look in, but asking them to give you a detailed answer without giving a detailed description of the current situation... they spend hours and days designing a suspension in a given space, then send it to lab and analysis departments, then tweaking and testing until the desired test results are achieved. you're asking them to take years and years of education and experience and condense it all into a post saying "use these values, see this sketch for reference".
Has anyone looked into transplanting some or all of the Pontiac Solstice suspension into a Fiero? I would think Pontiac engineers learned something since the Fireo and It would be one way of utilizing that knowledge and modernizing the Fiero.
My guess maybe is that Will has an aversion to engineers.
The languages used by professional engineers and hobbyist engineers is very different. Do you have any idea what the fundamental frequency of the Fiero suspension is? Of the body tub? Torsional stiffness?
the buick hyperstrut - http://blogs.insideline.com...mb-717x478-92946.jpg i think the strut idea is useless for the rear, but the KNUCKLE is very interesting, it could be used for a sla in the rear. the ball joints are moved closer to the rotor than others we had tried to check out several years ago. the scrub radius looks promising.
the compact car articles seemed to downplay drop knuckles in favor of springs. ? seems like knuckles would solve the geometry changes they were facing. the shot of the custom 88 rear knuckle was great. similar to a drop knuckle in that it moved the suspension points down, great cause there really is little room to move the inboard joints up.
i had the same problem with heim joints several years back, they wore out very fast. i used dust shields, they just fell apart and were useless. i even drilled them out for a "needle" grease gun fitting. helped a little. was it the "Speedway Motors" parts?
The languages used by professional engineers and hobbyist engineers is very different. Do you have any idea what the fundamental frequency of the Fiero suspension is? Of the body tub? Torsional stiffness?
Its funny you should say this, I worked for NASA a few years back with one of the leading physicist on harmonics and suspensions from Lockheed Martin on the IRED, Isolated Resistive Exercise Device. It's essentially a working platform that's connected to the bulkhead over the view port in Node 1 on the space station. I designed the platform and he designed the iso-links. Our job was to isolate the moments imposed on the space station structure by the working exercise platform in micro-gravity while the astronauts did their physical training.
Here my fat azz on the prototype during mock-up on the air bearing floor in building 9. Sorry for the bad pics, it was scanned in from a trade journal.
It was a lot of fun, even working with the Russians was okay if you could stand their chain smoking. ------------------ yellow 88 GT, not stock white 88 notchie, 4 banger
[This message has been edited by ccfiero350 (edited 08-29-2011).]
Has anyone looked into transplanting some or all of the Pontiac Solstice suspension into a Fiero? I would think Pontiac engineers learned something since the Fireo and It would be one way of utilizing that knowledge and modernizing the Fiero.
Gordon Murray said that the automotive problem is fundamentally one of packaging. Think about that for a minute and the answer should become apparent...
Gordon Murray said that the automotive problem is fundamentally one of packaging. Think about that for a minute and the answer should become apparent...
Not really. Anything is possible with enough time and money. My question was has anyone looked into doing this yet.
I don't have a Solstice to take measurements from to see if this is even practical. The main difference is the addition of an upper control arm to replace the strut in the rear. If I had access to the Solstice mounting point locations and component dimensions, I could answer the question myself.
Not really. Anything is possible with enough time and money. My question was has anyone looked into doing this yet.
I don't have a Solstice to take measurements from to see if this is even practical. The main difference is the addition of an upper control arm to replace the strut in the rear. If I had access to the Solstice mounting point locations and component dimensions, I could answer the question myself.
Getting components A and B to share the same location in space isn't possible, no matter how much money you have.
The Solstice suspension was designed for the Solstice, with packaging considerations totally different from those of the Fiero. Also, the Solstice is a front engine car, so roll axis inclination, etc. are not likely to be right for a mid/rear car.
Don't sell the Fiero suspension short. The reason it's not competitive has more to do with the lousy power to weight ratio in stock form than the suspension itself (at least the '88). When i get the car sorted out, it will be competitive for fast time of day, up there with the stock Z06's and Elises and various modified cars like the SBC 240Z, Rotary MG Midget, uber-boosted 240 SX and the like.
It may have already been discussed previously, but what characteristics that the car suffers from in stock form are you trying to address?
bump steer? pro-dive? pro-squat? roll center too low in relation to CG? loss of camber? ???
The C4 Corvette, Honda S2000 and Solstice GXP are in the same autocross class. Currently the top car nationally is the S2000. From what I've seen, it is a hard car to drive fast. Of the top 10 cars at last year's nationals, 8 were Hondas. 5th place was a C4, and 8th was a Solstice.
The Solstice suspension was designed for the Solstice, with packaging considerations totally different from those of the Fiero. Also, the Solstice is a front engine car, so roll axis inclination, etc. are not likely to be right for a mid/rear car.
Some rudimentary measurements from the parts in his second picture should tell him whether it's even possible to do.
The width of the transverse powertrain that has to fit between the upper control arm mounts really pushes the lower frame rails outward. This pushes the upper control arm inner pivots outward. If you can design a knuckle around this, you may make the whole thing work.
However, if you're dealing with a pre-selected set of geometry, your only option is just to keep pushing it further outboard. My guess, simply from looking at that picture, is that Solstice geometry grafted directly into a Fiero would end up with a hub-to-hub distance maybe 6 inches greater than that of the stock Fiero. If you're building an IMSA kit, that's probably fine. If you want to keep everything under the stock bodywork, that's more difficult.
[This message has been edited by Will (edited 08-30-2011).]
Some rudimentary measurements from the parts in his second picture should tell him whether it's even possible to do.
The width of the transverse powertrain that has to fit between the upper control arm mounts really pushes the lower frame rails outward. This pushes the upper control arm inner pivots outward. If you can design a knuckle around this, you may make the whole thing work.
However, if you're dealing with a pre-selected set of geometry, your only option is just to keep pushing it further outboard. My guess, simply from looking at that picture, is that Solstice geometry grafted directly into a Fiero would end up with a hub-to-hub distance maybe 6 inches greater than that of the stock Fiero. If you're building an IMSA kit, that's probably fine. If you want to keep everything under the stock bodywork, that's more difficult.
I have done the best "gestamating" that I can without having a Solstice or Sky to draw from and I do think this will fit in the Fiero. I cant find the measurments of the KAPPA suspension pinnings anywere. I have asked a few people who have one if they could help out with a few measurments and or pictures, but nothing yet. SO if anyone can help out with measurments of the KAPPA suspension geomitry I would VERY much like to have it So the best I can go by are the steering rack and sway bar widths. With them all bolted together and "mocked up" I have come up with some crude measurments. Those mesurments do allow this KAPPA suspension room to fit within the frame/ space. BUT this is a much wider suspension than the Fiero and would need a wide body kit or widened fenders.
If I remember right, the upper A arms do not have a clearance problem with the engine because they are stagered oposite of the lower a arms. the lower a arms are biased to the front of the car and the upper are biased to the rear. So one of the upper a arm mounts will nearly be mounted in the trunk, not next to the engine. Look close at where the drive shaft would go. Look at the coilover shock offset to the rear of the drive shaft. Then look at the a arms, how the upper wraps around the rear of the coilover shock and the lower A arm front side leg is near the crak pulley. The A arms are not an A, the upper "A" arm has one "leg" that runs directly over the drive shaft and one that runs away from the drive shaft. So the upper A arm needs a mount just over the top of the drive shaft and a mount over the top of the cradle mount bolt kind of in the trunk. The lower A arm is the same but has a mount under the tripot and the other mount some were near the crank pulley. Notice that the upper A arm is shorter than the lower and needs the mounts on the outside of the frame rails in the fender wheels.
The lower A arms look like they can be mounted directly to new mounting points welded on the cradle with little change in width from the stock Fiero pinnings.
[This message has been edited by Rickady88GT (edited 08-31-2011).]
BTW I have several pics of the front and rear suspension components side by side with the 88Fiero suspension. This KAPPA suspension is a MUCH better suspension than the 88 Fiero. The wheel bearings are all exactly the same on all four corners and are HUGE next to the Fiero bearings. The KAPPA is made to use MUCH larger wheels than the Fiero. 19" x 10" no problem as long as you have WIDE fenders. The KAPPA suspension is made to have a lower ride height from the factory than the Fiero. So you wont need to lower it and compromize geomitry. The brakes are 12" from the factory. Massive front rotor and a nonvented disk in the rear. The aftermarket can get you what ever spring rate you need to weight jack the car. The shocks are also aftermarket friendly. So "tuning" the suspension is possible. I think? the sway bars can be aftermarket as well for further tuning. It has the new style "ball joint" sway bar links. Several aftermarket brake upgrades to pick from. You could get poly if you want. Faster ratio power steering comes standard with a KAPPA swap. All this and I have not even mentioned the geomitry changes that could be better than the Fiero. Like adjustable caster in the front AND rear.
Has anyone looked into transplanting some or all of the Pontiac Solstice suspension into a Fiero? I would think Pontiac engineers learned something since the Fireo and It would be one way of utilizing that knowledge and modernizing the Fiero.
Yes, I have. I have the entire suspension steering and brake system from a Solstice- less the master/booster and rear sway bar. I have "mocked" it up within the rear clip of an 88. It looks VERY doable BUT I do not have the exact measurments I need to say for sure if it will work or not.
Yes, I have. I have the entire suspension steering and brake system from a Solstice- less the master/booster and rear sway bar. I have "mocked" it up within the rear clip of an 88. It looks VERY doable BUT I do not have the exact measurments I need to say for sure if it will work or not.
I think the proper approach is to do what was suggested in the other thread.
Determine the desired track, ride height and tire size and that will determine the general location of the lower control arm mounting points. This assumes you want a level lower control arm at the desired ride height (which may not be the case). From there you set the desired camber and that will give you an arc for the possible upper control arm mounting points. Then use a suspension geometry program to determine the best location on that arc. You also need to consider anti-squat and bump steer.
Mounting point measurements from the original car are only relevant if the track remains the same. They can also be used as a starting point and as a sanity check.
.JPG)
So the best I can go by are the steering rack and sway bar widths. With them all bolted together and "mocked up" I have come up with some crude measurments. Those mesurments do allow this KAPPA suspension room to fit within the frame/ space. BUT this is a much wider suspension than the Fiero and would need a wide body kit or widened fenders..JPG)
