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SSATB
SSATB New Reader
9/28/15 2:36 a.m.

I read somewhere that a well designed MacPherson setup is easier to drive at the limit and it isn't as inferior to double wishbone as is always claimed. One of best handling cars ever made is the Cayman. It's possible one of the reasons Porsche went with MacPherson all around is because, especially in the back, there probably isn't much space with the MR transaxle for a triangulated A-arm.

1) Do MacPherson struts offer any handling/ride quality advantages over DWB, for road cars?

2) Which, front engine, rear-wheel drive (FR) cars have MacPherson struts at all four corners (like the Cayman)?

Streetwiseguy
Streetwiseguy PowerDork
9/28/15 5:58 a.m.

1- No. Struts are cheaper, and take up less room.

2- 240Z Datsun.

3- You have possibly started a semantics discussion regarding the proper terminology of struts.

Kia_Racer
Kia_Racer Dork
9/28/15 6:13 a.m.

Do they have to be MacPherson? Chapman struts worked great on old Lotii.

The_Jed
The_Jed UberDork
9/28/15 7:35 a.m.

The '88-'94 Maxima and J30, I've always loved that generation Maxima.

Edit:

I missed the part about rwd... I was answering the thread title question. Oops.

GameboyRMH
GameboyRMH MegaDork
9/28/15 7:49 a.m.

Macstruts can have lower unsprung weight and allow for more steering lock, do those count as handling advantages for a road car?

Appleseed
Appleseed MegaDork
9/28/15 7:56 a.m.

For weirdness, the Lancia Stratos had double wishbone in the front and Mac struts in the back.

mndsm
mndsm MegaDork
9/28/15 8:05 a.m.

Ae101 corolla is a macstrut car.

Tyler H
Tyler H SuperDork
9/28/15 8:06 a.m.

A well-set-up car of any configuration handles better than one that isn't setup well. That's the culmination of my experience playing race cars.

fanfoy
fanfoy Dork
9/28/15 8:19 a.m.

For a ROAD car, Mac struts offer a bunch of advantages: Less un-sprung mass, less pivot points which results in better damping, fewer attachment points so lesser NVH...So for ride quality, that's a big plus.

And if you design them properly, on a full-bodied car, they can be just as good, handling wise, as DWB.

jstein77
jstein77 SuperDork
9/28/15 10:34 a.m.

The big disadvantage of a MacPherson Strut as compared to an A-arm suspension is a relative lack of camber change with travel, which makes it less able to compensate for body roll. This is frequently overcome by limiting body roll and using a large initial negative camber setting. For example, I use a 25 mm front anti-roll bar and 2.5 degrees of static negative camber on my Sentra to keep the tire square in hard cornering.

Nick (Not-Stig) Comstock
Nick (Not-Stig) Comstock PowerDork
9/28/15 10:47 a.m.

I prefer leaf springs

GameboyRMH
GameboyRMH MegaDork
9/28/15 10:54 a.m.
jstein77 wrote: The big disadvantage of a MacPherson Strut as compared to an A-arm suspension is a relative lack of camber change with travel, which makes it less able to compensate for body roll. This is frequently overcome by limiting body roll and using a large initial negative camber setting. For example, I use a 25 mm front anti-roll bar and 2.5 degrees of static negative camber on my Sentra to keep the tire square in hard cornering.

Another big disadvantage - which is more of an implementation problem - is that most cars with macstruts have the arms too close to level in their resting position. Ideally you want the arms slanting downward from the chassis to the upright at normal ride height. When the arm passes the level position in compression travel, the camber curve reverses itself - more compression creates positive camber and extension creates negative camber. Many stock vehicles can reach this point easily which requires even more body roll limitation. And if you lower it? Well you might as well use Chapman's "any suspension can work, if you don't let it" design because your camber curves will be mostly or entirely backwards.

(Edit: I should mention that the "level position" is affected by the strut angle, so in practice the reversion point is usually bit above the point where the inner bushing-to-balljoint angle is level, since struts are usually leaned inboard a bit (especially on the front). Adding negative camber with camber plates gives you a little more room to the reversion point this way.)

Jamey_from_Legal
Jamey_from_Legal Reader
9/28/15 11:14 a.m.

BMW E21, all 4 corners.

singleslammer
singleslammer UberDork
9/28/15 12:00 p.m.

Not front engine but the MR2 Spider is Struts all around. Those are a blast and handle great! Mine was brilliant on snow tires (less is more) and very fast on RE11s (Not as much fun though).

Knurled
Knurled UltimaDork
9/28/15 12:29 p.m.

None;.

They're called Chapman struts when in the rear

Knurled
Knurled UltimaDork
9/28/15 12:31 p.m.
GameboyRMH wrote: When the arm passes the level position in compression travel, the camber curve reverses itself

This is incorrect. The camber curve does not change signs until the angle defined by strut top - ball joint (or other pivot) - inner control arm/TCA pivot goes obtuse. Until that point, camber does still go more negative with bump travel.

Knurled
Knurled UltimaDork
9/28/15 12:33 p.m.
Jamey_from_Legal wrote: BMW E21, all 4 corners.

This is also incorrect - E21s, like 1600/2000 and E30 (and Z3/etc and E36 ti) are swing arm rear suspension. The spindle is attached to the swingarm, not the shock/strut.

RoddyMac17
RoddyMac17 New Reader
9/28/15 12:43 p.m.
They're called Chapman struts when in the rear

Not quite correct, the Chapman strut doesn't use a lower link, the driveshaft/halfshaft is the link (along the same lines as the Jaguar rear suspension). When Chapman changed the Lotus 16 halfsafts to a sliding spline, the rear suspension went from Chapman strut to MacP strut.

Trackmouse
Trackmouse HalfDork
9/28/15 1:27 p.m.

240z is dwb all four corners.

edizzle89
edizzle89 HalfDork
9/28/15 2:03 p.m.

aw11 mr2's are also mcpherson in all 4 corners

sethmeister4
sethmeister4 SuperDork
9/28/15 2:52 p.m.
Trackmouse wrote: 240z is dwb all four corners.

Pretty sure it's not at all. Struts front and rear, I think the rear is a semi trailing arm style, not totally sure if I have that right. Front is definitely strut, no DWBs anywhere.

alfadriver
alfadriver UltimaDork
9/28/15 3:01 p.m.
Tyler H wrote: A well-set-up car of any configuration handles better than one that isn't setup well. That's the culmination of my experience playing race cars.

That's all that needs to really be said.

Potential changes, but in the end, it's the final set up and calibration that really matters.

alfadriver
alfadriver UltimaDork
9/28/15 3:02 p.m.
SSATB wrote: I read somewhere that a well designed MacPherson setup is easier to drive at the limit and it isn't as inferior to double wishbone as is always claimed.

Low limits are very easy to deal with.

Matt B
Matt B SuperDork
9/28/15 3:10 p.m.

I thought Porsches used a multilink suspension in the back? They may use McPherson style strut, but I think there's more going on back there than the front setup.

Trackmouse
Trackmouse HalfDork
9/28/15 3:26 p.m.
sethmeister4 wrote:
Trackmouse wrote: 240z is dwb all four corners.
Pretty sure it's not at all. Struts front and rear, I think the rear is a semi trailing arm style, not totally sure if I have that right. Front is definitely strut, no DWBs anywhere.

We're both half correct.... A quick search shows front is mac rear is dwb. Wth Datsun.... Also, wth is wrong with me? I've owned three z's and a 510...

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