Poormans SVO style front suspension?

[Anlushac11]

I was reading the "How To Make Your Mustang Handle" book by Willam R. Matthis when something occured to me.

As many of you know the SVO has a narrower K-member and longer 14" long A-arms as opposed to stock Mustangs 13" long A-arms. The point of the long A-arms is to reduce the amount the suspension cycles up and down. On a Mustang when the suspension compresses the geometry changes for the worse so the long A-arm reduces the amount the suspension compresses.

The SVO is a sort of band aid fix from the factory to improve the Fox bodies handling defects that can only be cured by a double A-arm front suspension(very expensive).

The modified K-Member in Matthis book relocates the A-arm mounting bolt holes back and up 3/4".

What got me wondering was the pre-'88 K-members are 1" narrower than the '88-'93 K-member. So why not install 87-88 Tbird 13 3/4" long A-arms to get the improved length? You would still need to use caster camber plates and notch the K-member mounting holes to move K-Member forward 5/8" to improve braking anti-dive and braking squat.

The main reason for doing this would be to keep a stock looking front suspension because some racing classes dont allow aftermarket K-members.

It would not be as good as a SVO but it would use all stock Mustang parts and brakes so no custom parts and you would get some of the advantages of the SVO design.

So whats your thoughts?

 

[Stinger]

I don't see why it wouldn't work. I've heard of people using TC arms on Mustangs...

 

[svoman2300]

I know you said poormans but why not just get an SVO k member. I see them for sale once in a while for less than $100. Or you can get this http://www.slotcarracing.com/itm00015.htm Its cheaper than doing a tubular.

 

[Mustang5L5]

What got me wondering was the pre-'88 K-members are 1" narrower than the '88-'93 K-member.

Care to elaborate on that?

I was under the impression that all 79-93 Mustang K-members were the same except for SVO and the I-6 K-members

 

[DRAGPAK]

K -member

The svo and regular mustangs have the same k member .The lower control arms and spindels are different though.I own 2 svo and one 90 5.0 lx same k members.

 

[garry]

I have been thinking obout all this lots lately, I have an 88tc parts car that i want to as much of the suspension as I can onto my 83 capri. It has brand new struts and shocks, longer control arms and new springs and so on. But before i pull both cars apart I keep trying to find out exactly how many of these parts bolt right on and what others will work with mods.

 

[Anlushac11]

The svo and regular mustangs have the same k member .The lower control arms and spindels are different though.I own 2 svo and one 90 5.0 lx same k members.

'79-'88 Mustang K-member front A-arm bolt center to center - 22.75"
'89-'93 Mustang K-member front A-arm bolt center to center - 23.75"
Mustang SVO K-member front A-arm bolt center to center - 23.00"


'79-'88 Mustang K-member rear A-arm bolt center to center - 30.125"
'89-'93 Mustang K-member rear A-arm bolt center to center - 31.125"
Mustang SVO K-member rear A-arm bolt center to center - 29.5"

'79-'93 K-member angle of A-arm off centerline of car - 16.5 deg.
Mustang SVO angle of A-arm off centerline of car - 14.5deg.

'79-'88 K-member overall width from ball joint to ball joint - 51.37"
'89-'93 K-member overall width from ball joint to ball joint - 52.37"
SVO K-member overall width from ball joint to ball joint - 53.36"

Stock Mustang A-arms '79-'93 - 13.00" long
Mustang SVO A-arms - 14.00" long
1987-1988 Thunderbird A-arms - 13.75" long.

The SVO used a special K-member to mount the '83-'84 Lincoln Continental A-arms and brakes. The '87-'93 Mustang uses a 4 lug version of the same rotor but a revised spindle design so it can work on stock Mustang ball joints. Thats why I am using a 83-84 Lincoln Continental 5 lug rotor to convert the front to 5 lug.

The reason for using this setup would be

1) Using the longer A-arms reduces the effect of the bad things that happen when the Mustang suspension cycles because it has no upper A-arm.

2) Except for the Thunderbird A-arm, which uses the stock Mustang A-arm bushings and ball joint, all the parts are stock Mustang.

3) SVO parts are becoming hard to find in good shape. Also my research says that when the stock SVO A-arm bushings wear out the only replacement is a aluminum bushing from Global West.

4) By using stock Mustang parts at a later date you can upgrade to SN95 front brakes and from there upgrade later to Cobra 13" front brakes if you so desire.

Plus in another 10 years how hard will it be to find 87-93 Mustang brake parts? Mine will be upgraded to SN95 front brakes as soon as I get the money.

Also If you use the Lincoln brakes you have to get a spacer or shim to go over the ball joint to hold the Spindle properly. But if you use the 87-93 Mustang spindle with the 83-84 Lincoln rotor and Lincoln or SVO 73mm calipers you can run the best of both worlds.

 

[David Wilkinson]

I've been considering doing this as I have a spare k-member (on a parts car) and T-bird control arms. My understanding is:

Longer arms: Decrease camber change as suspension compresses,
moving k-member forward: increase positive caster, to increase the tendency of the steering wheel to "hunt center", and changes weight distribution.
Canting control arms: increase brake anti-dive

(I'm going from memory, as i've lent my copy to a friend)

I'm not sure I'll want to change the anti-dive (Maximum Motorsports seem to think the stock anti-dive is just fine, http://www.maximummotorsports.com/kmember.asp ), but the other changes sure seem interesting.

It seems to me Mathis considered the '89+ k-member to have superior geometry, or am I mistaken?

BTW, Energy Suspension lists a different bushing for the T-bird control arms, and they appear bigger to me (relative to the Mustang bushings).

Dave

 

[Mustang5L5]

'79-'88 Mustang K-member front A-arm bolt center to center - 22.75"
'89-'93 Mustang K-member front A-arm bolt center to center - 23.75"


'79-'88 Mustang K-member rear A-arm bolt center to center - 30.125"
'89-'93 Mustang K-member rear A-arm bolt center to center - 31.125"

'79-'93 K-member angle of A-arm off centerline of car - 16.5 deg.

'79-'88 K-member overall width from ball joint to ball joint - 51.37"
'89-'93 K-member overall width from ball joint to ball joint - 52.37"

Stock Mustang A-arms '79-'93 - 13.00" long

How is that possible?? That's a 1" change of the front track from 79-88 to 89-93. That's 0.5" each side up front. I've never heard of this ever when i was researching all my 5-lug brake conversions (Both SVO and later Sn95 Cobra). All the literature i have read puts the front track as constant from 79-93. Even the aftermarket lists all the dimensions for K-members from 79-93 as being the same. This 1" difference is a big deal. Some guys (myself included) try to avoid the 96-later spindles when doing Sn95 conversion because they push the front wheels out 8mm. That's only 1/8th of an inch each side and that was a big deal to me.

What is your source for your information?

Not that i'm trying to shoot you down, it's just that i've spent a lot of time researching offsets and suspension changes and such and this is big to me. I've always believed that all 87-93 Mustangs had the same exact K-members and until i get solid proof i'm still going to beleive this.

 

[svoman2300]

The info is from "Mustang Performance Handbook 2" by William R. Mathis. I suggest that anybody interested in modifiying the suspension on their Mustang get this book. It is very technical and will make your head spin if you are not an engineer. http://www.amazon.com/exec/obidos/t...f=sr_1_1/002-6659275-4701660?v=glance&s=books