Suspension MM K-member. 0-offset of reverse offset arms?

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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So...starting to look forward. Engine will be coming out this upcoming summer and I want to do a K-member while i'm there.

The MM k-member movese the front wheel forward 3/4" unless you use the reverse offset arms which move them back to stock location. My question is, what mods, if any, are needed to leave the wheels positioned 3/4" forward? On paper it sounds like a great idea, but what I don't want to do is start trimming my fenders or removing the liners and such.

Does anyone run this k-member and arms with the wheel moved forward 3/4"?
 
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I was under the impression the forward offset was more for road racers than street drivers. I also gotta believe it messes with the sway bar too.
If I was to ever switch to an MM k (maybe one day, but i'm just not up for a project of that magnitude at this point, especially since my drivetrain is aligned for the poorly designed AJE), it would be stock offset for sure.
I know too you talked about the 96+ arms with their K also, i'd be mindful of the extra width. I read MM's reasoning on those arms with the K, but basically all I got out of it is that you can use less spacers on the bolt through tie rods, i'll assume for less deflection under hard cornering.
3/4 out, 3/4 forward, sounds like a lot of change to me (if those are the numbers)
All this leads me to believe that road racers are much more likely to use wheels and tires that match the suspension, where the street guys would prefer to match the suspension to the wheels.

I just don't believe guys like you and I need every last ounce out of the suspension.
At this point to get a thrill out of pushing the car, i'd need to be driving like 80mph on a 25mph bend.
Maybe some of the guys that say it's more fun to drive a slow car fast than it is to drive a fast car slow are right...
 
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After googling for a few days, I think I've come to the same conclusion as you stated. For my use, best to just stick with close to original positioning.

I think you are right that MM's reasoning for changing spindles (you said arms but I think you meant spindles) is purely stack-up on the tie rod end. The k-member moves the rack slightly and with the relocated A-arm pivots (also moved up) it's almost 1" of stacked spacers that would be eliminated going with the 96+ spindles. Probably not a big deal in street driving, which is my purpose but I believe I read about on another forum @MFE92 experiencing flex while turning with a tall bumpsteer stack.

But, in converting to bolt-through bumpsteer kit (which is required according to MM), I need to drill the spindles off the car anyway. Given I've seen the 96+ spindles much cheaper, I figure I could keep an eye out for a pair to drill and then just swap spindles and sell off my 94-95 spindles for more. According to MM, the 96+ spindles only go out another 5mm over the 94-95. ( 94-95 are 3mm more than fox and 96-04 are 8mm, but 5mm difference between the two). That 5mm could make a difference when it comes to tire clearance to the coil-over setup. Now, I don't know what my clearance is since i'm just on the verge of putting the coil-overs in, so we will need to see how badly I need more room when that time comes. I do know I do NOT want to run a spacer. So i'll prob think about this a little more. Probably not necessary, but if my coil-overs are close to my tires, that might make the decision for me.

But it is a pricey setup. K-member, arms, rack bushings, and shorter sway bar endlinks....$1150. Ouch. Can probably knock $100-200 off that waiting for LMR 10% discount promos on the K-member+ arms package they offer, or MM's weekend deal packages for the other items (usually a discount plus free ship).
 
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I see pretty much no way you could have a clearance issue with the tires and the coil overs unless you are using massive front wheels.
For argument sake I went out in the garage and took a look. While I have the car too high to reach with a measuring tape to go from coil to wheel/tire, it's at least 1.5 inches, more like 2 inches.
That's with an 8.5 wheel with MM coil overs.
 
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After googling for a few days, I think I've come to the same conclusion as you stated. For my use, best to just stick with close to original positioning.

I think you are right that MM's reasoning for changing spindles (you said arms but I think you meant spindles) is purely stack-up on the tie rod end. The k-member moves the rack slightly and with the relocated A-arm pivots (also moved up) it's almost 1" of stacked spacers that would be eliminated going with the 96+ spindles. Probably not a big deal in street driving, which is my purpose but I believe I read about on another forum @MFE92 experiencing flex while turning with a tall bumpsteer stack.

But, in converting to bolt-through bumpsteer kit (which is required according to MM), I need to drill the spindles off the car anyway. Given I've seen the 96+ spindles much cheaper, I figure I could keep an eye out for a pair to drill and then just swap spindles and sell off my 94-95 spindles for more. According to MM, the 96+ spindles only go out another 5mm over the 94-95. ( 94-95 are 3mm more than fox and 96-04 are 8mm, but 5mm difference between the two). That 5mm could make a difference when it comes to tire clearance to the coil-over setup. Now, I don't know what my clearance is since i'm just on the verge of putting the coil-overs in, so we will need to see how badly I need more room when that time comes. I do know I do NOT want to run a spacer. So i'll prob think about this a little more. Probably not necessary, but if my coil-overs are close to my tires, that might make the decision for me.

But it is a pricey setup. K-member, arms, rack bushings, and shorter sway bar endlinks....$1150. Ouch. Can probably knock $100-200 off that waiting for LMR 10% discount promos on the K-member+ arms package they offer, or MM's weekend deal packages for the other items (usually a discount plus free ship).

Good; because whatever you come up with is probably what I will do to mine. :nice:
 
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I have a MM modular swap k member (don’t know if this matters) and used the reverse offset control arms for a few years. I hated it. The reverse offset control arms completed eliminated the Ackermann effect. The steering never felt right. At parking lot speeds when turning sharp, the front end would push. You could hear the tires sliding. I even set the tow to zero hoping to get some ackermann back, but it still wasn’t right.

I’m now using the standard offset arms. I did have to trim the lower fender spats, but I have the 87-90 fenders. I also went to narrower front tire.

5F05E610-6857-484A-B613-7334590B3DD5.jpeg

A6B4A029-8B55-4A3E-8E4A-0D50070797F4.jpeg


MM sent me a word doc explaining the necessary modifications. I’ll try to find it if you’re interested.
 
If I were doing it all over again, I'd do their reverse offset arms that keep the wheels positioned like stock. I'm just not sure the forward offset gives a performance gain that's worth the PITA it causes with fender clearance etc.
 
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@Mustang5L5
You undoubtedly noticed that the stock K member is a massive, heavy piece of metal.
It is like that for a purpose; if you live in a place that is snow and ice for the winter, the roads have some very nasty potholes that bend and break things. That mass and weight is to resist such damage and it does a pretty good job of it.

All aftermarket K members are made with running on a nice smooth racetrack with no potholes, curbs or drop-offs. Because of this design, they can be made with materials and techniques that save weight and reduce the mass. Running this type of K member in a street environment is not a good plan since it invites bent and buckled tubes and pivot points when a killer pothole or high curb or drop off on the edge of the road is encountered.

Someone will undoubtedly say that the aftermarket K member is made of high strength chrome-moly steel. While that may be true, the steel tubing isn't designed to take the sudden shock loads. These can occur when you hit a curb, drive over a pothole or go off the side of the road and it is a big drop from the paved road surface.. Being cautious isn't always the solution since the roads are filled with people and things that have little or no concern for you or your precious modified car.
 
@Mustang5L5
You undoubtedly noticed that the stock K member is a massive, heavy piece of metal.
It is like that for a purpose; if you live in a place that is snow and ice for the winter, the roads have some very nasty potholes that bend and break things. That mass and weight is to resist such damage and it does a pretty good job of it.

All aftermarket K members are made with running on a nice smooth racetrack with no potholes, curbs or drop-offs. Because of this design, they can be made with materials and techniques that save weight and reduce the mass. Running this type of K member in a street environment is not a good plan since it invites bent and buckled tubes and pivot points when a killer pothole or high curb or drop off on the edge of the road is encountered.

Someone will undoubtedly say that the aftermarket K member is made of high strength chrome-moly steel. While that may be true, the steel tubing isn't designed to take the sudden shock loads. These can occur when you hit a curb, drive over a pothole or go off the side of the road and it is a big drop from the paved road surface.. Being cautious isn't always the solution since the roads are filled with people and things that have little or no concern for you or your precious modified car.

MMs goals were geometry and rigidity. It's a lot heavier than K members you may find elsewhere that are for all intents and purposes, track pieces. It is more rigid than the stock piece and in the end, came out 11 lbs lighter than stock.

If anyone knows of one that has broken, I'd love to see the pics.