My friend who builds dragsters can build some subframe connectors for our cars. He's pretty much a metal guru and can do anything. He even welded my cams on my SHO for me. We haven't come up with a design yet or even prices, but I want to see what type of interest there is before we go further with this. We need about 5-10 people to keep costs down.
Who's up for some subframe connectors?
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I think you'll need to explain more as to the purpose of them, for a lot of people here.
EVERY car has isolated subframes. All that means is it has rubber bushings. Ford Racing has SFC's for the Mustang, and it has an ISC. Unless there's something you know that FR's engineers don't, there's no problem with installing them.
Right, because the dynamics of a solid axle RWD car are exactly the same as the FWD independant suspension Fusion.
Think about this, when you load up the car in the corner, the lateral loads compress the rubber in the subframe bushings. This causes the subframe to shift relative to the body. The orignal engineers tune this and the other bushings so that the shift of the subframe is integrated with the other compliances in the suspension. If you start tying the rear and front together, you will alter the way the subframes shift, probably causing them to twist, rather than shift. This will find it's way back to the wheel, resulting in toe-changes that could reduce the steering feel, alter the balance and introduce unprefictability.
It could turn out to be better though, so I say try it out. But I just want to point out that there's a lot more to suspension tuning then people often realize.
And not all cars use isolated subframes, though it is becoming the only way to meet the NVH requirements of the market. I remember reading that the Accord uses isolated subframes on the I4 models, but not the V6, or it could be the other way around. The Ford 500 uses an isolated rear subframe on AWD models but not FWD.
Think about this, when you load up the car in the corner, the lateral loads compress the rubber in the subframe bushings. This causes the subframe to shift relative to the body. The orignal engineers tune this and the other bushings so that the shift of the subframe is integrated with the other compliances in the suspension. If you start tying the rear and front together, you will alter the way the subframes shift, probably causing them to twist, rather than shift. This will find it's way back to the wheel, resulting in toe-changes that could reduce the steering feel, alter the balance and introduce unprefictability.
It could turn out to be better though, so I say try it out. But I just want to point out that there's a lot more to suspension tuning then people often realize.
And not all cars use isolated subframes, though it is becoming the only way to meet the NVH requirements of the market. I remember reading that the Accord uses isolated subframes on the I4 models, but not the V6, or it could be the other way around. The Ford 500 uses an isolated rear subframe on AWD models but not FWD.
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Waldo: I like this, you really cause us to think about what is really going on under our feet and you are right about the sub frames. Many of the old uni-body Fords did not have them and yes, there was a lot of noise transmitted. I do appreciate your insight. :atl:
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[quote author=Waldo link=topic=39177.msg571731#msg571731 date=1139355108]
And there all made by the OEM's right? If they were so great, don't you think they'd come from the factory?
Sorry for the extra information. I will let the ignorance continue from now on.
[/quote]
I don't know the answer to any of this, or anything about it, but:
A lot of "great" things don't come from the factory. What's good for one application is not necessarily good for another, and what's good for a stock car is not necessarily good for one using a certain setup, or wanting a certain ride.
And there all made by the OEM's right? If they were so great, don't you think they'd come from the factory?
Sorry for the extra information. I will let the ignorance continue from now on.
[/quote]
I don't know the answer to any of this, or anything about it, but:
A lot of "great" things don't come from the factory. What's good for one application is not necessarily good for another, and what's good for a stock car is not necessarily good for one using a certain setup, or wanting a certain ride.
The Fusion chassis is fairly stiff from the factory, so subframe connectors seem like a bad idea until someone has done rather extensive modding. Keep in mind also that subframe connectors completely change the crumple zones of the car and might make it very unsafe in an accident. Many places will not accept a car with subfame connectors as a trade-in due to this.
[quote author=MZ6ZoomZoom link=topic=39177.msg572726#msg572726 date=1139417891]
I don't know the answer to any of this, or anything about it, but:
A lot of "great" things don't come from the factory. What's good for one application is not necessarily good for another, and what's good for a stock car is not necessarily good for one using a certain setup, or wanting a certain ride.
[/quote]
This is very true. My only point was to present a bit more information so some of these trade-offs can be better understood. My opinion is that the chassis is stiff and the subframe bushings are very small and stiff. Thus all the complaince is in the suspension. The best approach would be to start stiffening up the control arm bushings first. Then the subframe will become the weaker link, and subframe connectors, or simply solid subframe mounts might have some benefit.
I don't know the answer to any of this, or anything about it, but:
A lot of "great" things don't come from the factory. What's good for one application is not necessarily good for another, and what's good for a stock car is not necessarily good for one using a certain setup, or wanting a certain ride.
[/quote]
This is very true. My only point was to present a bit more information so some of these trade-offs can be better understood. My opinion is that the chassis is stiff and the subframe bushings are very small and stiff. Thus all the complaince is in the suspension. The best approach would be to start stiffening up the control arm bushings first. Then the subframe will become the weaker link, and subframe connectors, or simply solid subframe mounts might have some benefit.
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