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Inboard Suspension
scootz - 8/9/08 at 07:38 PM

What are the pro's?

Worth the hassle?

PS - Also have a thread about centre-lock wheels on the go too if you want to contribute

tegwin - 8/9/08 at 08:45 PM

Less unsprung weight....Less aerodrag...Allows for progressive suspension (Provided you get the pivots right)


More complex, potentially heavier, takes up valuble space for radiator/engine...

IMHO...Pointles on a s7even....But worth doing if you want some fun

[Edited on 8/9/08 by tegwin]

gazza285 - 9/9/08 at 03:59 AM

quote:
Originally posted by tegwin
Less unsprung weight


Explain? More components usually, or larger wishbones/rockers to cope with the additional forces.

nick205 - 9/9/08 at 09:23 AM

quote:
Originally posted by gazza285
quote:
Originally posted by tegwin
Less unsprung weight


Explain? More components usually, or larger wishbones/rockers to cope with the additional forces.



(slightly) Lower weight is achieved if you use a pushrod where the shock would usually reside and have a rocker arm pivoting where the shcok top mount would usually sit. The shock then sits in the chassis (see MNR chasis for e.g.).

IMHO the unsprung weight saving is marginal in comparison to fitting light weight calipers or uprights, where the weight has more effect as it's furthest away from the pivot points.

One major benefit of this arrangement is that you can use a pushrod with adjustable rod ends adjust the front ride height of the car without compromising the travel or spring pre-load of the shock. If chosen carefully you could use shocks without adjustable spring platforms.

The other method of using the entire op wishbone as the rocker arm probably does increase the overall weight and doesn't have the additional ride height adjustment benefit.

[Edited on 9/9/08 by nick205]

[Edited on 9/9/08 by nick205]

02GF74 - 9/9/08 at 09:50 AM

inboard means your springs and shocks are out of the elements so will rust less.

iank - 9/9/08 at 09:56 AM

quote:
Originally posted by 02GF74
inboard means your springs and shocks are out of the elements so will rust less.


But on the downside get hotter (in a 7)

IMO If you're designing from scratch then why not - Sylva cars use them and handle extremely well - if retro fitting then almost certainly not worth the effort.

gazza285 - 9/9/08 at 05:51 PM

quote:
Originally posted by nick205
quote:
Originally posted by gazza285
quote:
Originally posted by tegwin
Less unsprung weight


Explain? More components usually, or larger wishbones/rockers to cope with the additional forces.



(slightly) Lower weight is achieved if you use a pushrod where the shock would usually reside and have a rocker arm pivoting where the shcok top mount would usually sit. The shock then sits in the chassis (see MNR chasis for e.g.).

IMHO the unsprung weight saving is marginal in comparison to fitting light weight calipers or uprights, where the weight has more effect as it's furthest away from the pivot points.

One major benefit of this arrangement is that you can use a pushrod with adjustable rod ends adjust the front ride height of the car without compromising the travel or spring pre-load of the shock. If chosen carefully you could use shocks without adjustable spring platforms.

The other method of using the entire op wishbone as the rocker arm probably does increase the overall weight and doesn't have the additional ride height adjustment benefit.

[Edited on 9/9/08 by nick205]

[Edited on 9/9/08 by nick205]



The push rod sits where the shock sits, yes I agree, but the shock still contributes the same weight to the unsprung weight wherever it sits as the same portion of it is unsprung, so all you have done there is add the weight of the pushrod to the unsprung weight you already had. No reduction in unsprung weight at all, but an increase.

nick205 - 9/9/08 at 07:27 PM

Agreed - the overall weight goes up, but in real terms the effect should be an improvement (albeit marginal) as the weight moves closer to or the other side of the pivot points and towards the centre line of the car.

[Edited on 10/9/08 by nick205]

NS Dev - 10/9/08 at 12:24 PM

Pointless on a 7 type car really.

If you fancy the engineering challenge, there's no harm done, but not necessary.