View Full Version : Rear Suspension: Four Link vs. Three Link?
Loren
05-07-2012, 10:42 PM
(I hope you guys don't mind questions that have answers that are probably obvious to people more knowledgable about cars than me.)
In perusing the FF order page for the '33 I see that a "four link" rear suspension is standard, and a "three link" is described as an upgrade that costs $599 more. I have no idea what a four link, three link (or two, one, or no link) suspension is. Can someone explain them in fairly simple terms?
Why is the three link better? Is it an advantage on the street or the track—or both? What are its disadvantages compared to the four link?
I want to build the best '33 for me that I can, but I have no basis for choosing one or the other, other than that the three link is an "upgrade".
My '33 would be built with full fenders, the hard top, and would go out for autocross and track lapping days (but no wheel to wheel racing) and it must be well-mannered enough on the street that my girlfriend (and wife of 27 years) will be happy to go for rides with me.
Three links or four?
Thanks in advance for replies.
j33ptj
05-08-2012, 12:57 AM
The number of links refers to how many "connections" there are between the rear axle and the frame, excluding the dampners and drive shaft.
So a four link has two connectors that go from the dif to the left and right side of the vehicles in a \/ shape, and two links straigt' so it sorta looks like this |\/|
A three link as three (duh!), not 100% sure how they run, but supposedly(?) give better cornering behaviour, while the four link is better for straight "dragging"
Jeeps have a five link: Two upper and lower control arms on each side and a Track bar across the vehile.
Suggest googling it for more information!!
Robert
Loren
05-08-2012, 11:00 PM
Thanks for the reply.
Yes, I googled and wiki'd and got basic descriptions of the geometry, but not much about the advantage/disadvantage tradeoff, and of course nothing about how it might apply to a FF '33.
Given how I plan to use the car, three link sounds better for me if it improves cornering. Any other advantages/disadvantages as it applies to the FF '33?
Loren,
Based on how you intend on using the '33, go with the 3-link.
Olli
Sailor
05-09-2012, 08:01 PM
So your girlfriend AND your wife of 27 years need to be happy to go for a ride with you? Is there going to be a rumble seat or will they have to take turns? :D
riptide motorsport
05-09-2012, 08:49 PM
depends what you want to do with the car,,,if your just driving it with the ocasional drag strip run, then a 4 link is fine....if your going to do some form of competitive racing the 3 link is for you......Steven
edwardb
05-09-2012, 09:25 PM
Well, I'm a Roadster guy, but this point is widely debated over there as well. For Roadsters, one of the options is also IRS, but that's another discussion. The explanation about the number of links is correct. The comment about depending on how you're going to use the car is very important. Although the most economical, the problem with the 4-link set-up is that in certain situations the geometry can "bind" and then come loose unexpectantly with unpredictable handling results. Quick snaps and/or spins can and do result. The 3-link doesn't have the binding problem, so is more predictable and can be taken to the extreme more reliably. Having said that, though, with aftermarket parts, like those included with the kit (Koni coil-overs, control arms, better bushings) the 4-link is OK and can actually handle more power and is better for straight line launching.
So if you're only going to drive in the street, not go to the edge e.g. track, auto-x, etc., the 4-link can be an acceptable and economical option. But the 3-link will definitely give more reliable handling, and most would agree is the preferred setup between the two.
Having said all that, my Roadster is a 4-link, with all aftermarket parts. I just using it for street cruising, and I'm very happy with it. No complaints at all. For my use, it's fine.
ehansen007
05-10-2012, 10:51 AM
To me it seems more simple in that with the four link you're looking at up and down movement and with the three link you get more of a pivot point allowing the fixed axle move more freely and arc as it's moving up and down. Does that sum it up? You also get to adjust the pinion angle to match the ride height of the car.
Loren
05-10-2012, 03:43 PM
Thanks for all the replies, that's just what I needed to learn.
I'm hoping to go with the 5.0 Coyote, 412hp, and I hope that's not too much to go with the three link.