Honda suspension comparison.

[Bludger]

Which is the better design and why?

ED, EF, DA etc. single arm front LCA + castor rod

OR

EG, DC, EK etc. A arm front LCA

Which do you think is better and why?

What are the pro's & con's of each design?



I'm biased and don't like late model strut based front suspension from Honda.

[yourfather]

where does DC2R fit into this?

[Bludger]

where does DC2R fit into this?

EG, DC, EK etc. A arm front LCA

there

[chargeR]

Macpherson strut with A arm LCA. It is the awesome. Didn't vote because there wasn't an option for me .

[string]

I voted radius rods because they are easily replaced with a spherical and can be adjusted for castor in a much wider range without binding than the EG/DC arms with 2 bushings. I am also biased because I've owned 3 DA's

In terms of performance they will be very similar. I can't back this up but I believe the EG/DC suspension is mounted higher on the chassis than the DA so you can get the centre of gravity (CG) lower without running out of suspension travel. When your tyre is lowered to the guard (tiny gap) you have maybe 2cm of space between the upper control arm and the fender wall. Not good...

With no radius rod you probably don't need a very big front cross-member. I've never seen a EG/DC front cross-member but I imagine it is smaller than the DA's. Moving weight closer to the CG is always a good thing.

A likely possibility is that the EG/DC lower A-arm is cheaper to produce and they simply want to save money. They've (and any other business you can name) done it before; DC5 Macpherson Struts a perfect example. Another is the new Civics with their terrible rear suspension. Money money money.

[Bludger]

Macpherson strut with A arm LCA. It is the awesome. Didn't vote because there wasn't an option for me .

yeah, just cos you have a dc5

I voted radius rods because they are easily replaced with a spherical and can be adjusted for castor in a much wider range without binding than the EG/DC arms with 2 bushings. I am also biased because I've owned 3 DA's

In terms of performance they will be very similar. I can't back this up but I believe the EG/DC suspension is mounted higher on the chassis than the DA so you can get the centre of gravity (CG) lower without running out of suspension travel. When your tyre is lowered to the guard (tiny gap) you have maybe 2cm of space between the upper control arm and the fender wall. Not good...

With no radius rod you probably don't need a very big front cross-member. I've never seen a EG/DC front cross-member but I imagine it is smaller than the DA's. Moving weight closer to the CG is always a good thing.

A likely possibility is that the EG/DC lower A-arm is cheaper to produce and they simply want to save money. They've (and any other business you can name) done it before; DC5 Macpherson Struts a perfect example. Another is the new Civics with their terrible rear suspension. Money money money.

Honda torsion beam FTL, as well as every other manufacturer....

good point about moving weight rearward to center, never thought of that, and no, eg/ek/dc's don't have a front cross-member at all.

[JohnL]

Macpherson strut with A arm LCA. It is the awesome. Didn't vote because there wasn't an option for me .

Any of the SLA ('double wishbone') front suspensions will in principle be superior to the Mac Strut. Having said this, a sensibly modded Mac Strut will be superior to a poorly modded (or designed) SLA suspension, but all else being equal the SLA will be better out of the box (typically, but the Devil is in the detail), and have more scope for improvement, especially for a FWD car.

Mac Struts are a very compromised design, but do have advantages in that they are compact (easier to package into the chassis due to lack of upper wishbone), they are robust, they are lightweight, and they are relatively cheap to make.

Did I say they were cheap?

On the other hand Mac Struts don't change camber enough with suspension motion (which makes them very sensitive to body roll causing substantial unwanted camber change relative to the road surface), the caster angle unavoidably changes with suspension motion, the damper is subject to quite substantial internal loadings that are the result of lateral forces and braking forces being reacted within the damper body (between the piston and the damper tube wall).

This latter problem isn't an issue for SLA suspensions because all forces (other than vertical ones which the damper is well suited to dealing with) are reacted through the upper part of the suspension 'upright' (aka 'knuckle' etc) and in the upper wishbone (not in the damper), but with a Mac Strut the damper body and rod are forced to act as if they were the suspension upright....

Mac Struts are not well suited to wider tyres due to the limited camber change, and tend to require excessive static neg camber angles to compensate for this (more so with wider rubber), but this causes other problems...

Even with substantial static neg camber this does not really make up for the geometric deficiencies of a Mac Strut, just alleviates them somewhat by maximising the lateral grip of the outside front contact patch (i.e. pre existing static neg camber helping to keep the OF wheel near vertical when cornering hard) at the expense of the inside front contact patch, which ends up being very small with a very substantial dynamic camber causing the tyre to be running on it's very inner edge.

Sure, Porsche use Mac Struts on the 911, but on these cars not much is really asked of the front end, all (most of) the lateral and longitudinal traction action occurs at the back end due to the heavily rearward weight bias and the need for rear traction dictating a relatively very roll stiff front end that unloads the inside front wheel very substantially when cornering (thus the dynamic camber angle and grip of the IF is laregely irrelevant...).

Now for a FWD car we need to keep the inside front contact patch planted heavily on the ground (i.e. low front roll stiffness relative to rear roll stiffness) and presented as 'squarely' to the road as we can manage in order to maximise it's grip in order to minimise understeer and maximise traction exiting corners. This is not acheived if we allow the IF to lean over at drunken angles with only it's inner edge in road contact, yet this is what we are more or less forced to do when setting up a Mac Strut for 'high performance' applications.

When trying to get the most out of a Mac Strut design, we can't really make a silk purse out of a pig's ear (Mac Strut = pig's ear), at best we can make a purse that looks a lot less pig's ear-like than it actually is...

Note that for all purpose designed modern race cars (not racers made out of modded road cars), SLA is the suspension of choice at every corner of every car...

[Bludger]

LOL

was waiting for your post

[Bludger]

but you didn't make much comment of the two suspension designs compared in this thread

[SHOGUNOVDDRK]

Where is the AH suspension systems Bau?

Where?

Not saying I'd vote for it but its something to consider.

[Bludger]

Would be nice to have the A arms with radius rods.

I guess that is possible by getting hold of one of the many brands of traction bars.

[SHOGUNOVDDRK]

*rubs Torsion Bars*