MK4 spindles vs SN95 spindles

[Packer fan]

Hi all,
I am curious about opinions between MK4 spindles and SN95 spindles.
I am building a car because I have always wanted to build a car and because I would love to have a great handling fun car. Back when I ordered the kit around the first of the year there was a sale that when you buy any kit all of the accessories were 1/2 off. So I called FFV and asked if that meant I could order a basic kit and order all of the rest of the parts at half off. The person at FFV said yes, and it sounded like that was what most had done. I called FFV a few days after ordering it to talk to someone to make sure I had everything on order. They said it looks like I did and we made a couple small adjustments to the order.

Fast forward to almost 2 weeks ago. I realized that I was missing several things (never ordered).
One of them was the front spindles. After calling them and discussing it with them it was explained that there were 2 types. One using an adapter that I already installed and the other not needing the adapter. Same price. I wasn’t told that there was a difference in handeling. Since I had already installed the adapter I said I’ll take the ones requiring the adapter.

Today I was trying to see which set of holes to use on the adapter depending on the year of the spindles and I saw the description of the 2 styles and it says that the non adapter version has much better handeling. I think that I would like to return them and get the better ones. It will cost 2 more shipping costs and a restock fee.

Any thoughts?

[steno]

What type of driving do you intend to do?

[videodude]

There is a difference between the Fox, SN95, and FFR spindles that goes beyond the adapter. I had this same question and have spent more hours researching it than I would have liked to, but here's the short answer: Best handling "out of the box": FFR spindles. Second best: SN95 spindles WITH the SAI mod kit (which does not appear to be available anymore, from anyone). Third best: SN95 spindles "as-is". Fourth best: Fox spindles.

The issue is bump steer (when you go through a bump, the car takes off in another direction). The "fix", developed by Dave Borden, is called the SAI "mod". SAI stands for Steering Axis Inclination, and there is a highly detailed explanation of it on both forums that can be found by searching. Bump steer happens. Detroit engineers it out, for the most part. My Mercury Mountaineer (Explorer on steroids) doesn't have any. My wife's new Ford Fusion has a very small amount. Her Miata doesn't like bumps, driving on the freeway at speed is always an adventure. The SAI mod was developed to correct the inclination angle of the spindle in order to allow for more accurate alignment through the suspension travel range.

The FFR spindle is a custom made piece that incorporates the SAI mod parameters into a single spindle that provides these functions. The SAI mod works, but not quite as well. With Power Steering you might not even notice it. The cost of the SAI mod (if you can find a kit) and the value of the SN95 spindles about equals the cost of the FFR spindles, so it's pretty much a wash.

As for me, I'll be ordering the FFR spindles with my kit, even though I have a pristine set (2, actually) of SN95 spindles. It's simpler, and it's 4 less bolts in the suspension. Yes, I'll be using power steering, and probably won't notice, but I'll know it's there.

HTH,

Video

[edwardb]

The purpose made Factory Five spindles are superior to the unmodified Mustang donor spindles. They don't require any adapters, and have the various "fixes" developed for the Mustang spindles e.g. bump steer/SAI mod, designed in. Some Mustang spindles are better than others. But I've driven both and the Factory Five spindles are hands much down better. Strongly recommend that's what you use for your build. For some shipping costs and restock fee a no-brainer IMO. You've got a nice build going there (Coyote, T-56, IRS). Deserves to have the best spindles.

Edit: Videodude and I posted at the same time. Looks like we're on the same page.

[Packer fan]

Thanks Videodude and edwardb,

I was leaning that way. I didn’t know what the MK4 spindles fixed. Now that I know it’s bump steer, I definitely want it.

The car will be used for spirited driving and I would love to try some track days also.

[Packer fan]

Next question
How do I remove the spend less adapter that I put on so that I can install the mk4 spindles?
I can’t get it odd the tapered shaft��

[CraigS]

Use one of these
https://mobiledistributorsupply.com/...ABEgKOWfD_BwE#
I am making the assumption that you have these hanging from the upper ball joint
http://www.factoryfiveparts.com/1250...apter-bracket/
If that is the case it's not going to be easy. Usually you have a spindle below it that is also attached to the LCA. W/o those parts, the adapter will be flopping around when you try to hit it. You may end up needing to destroy the upper BJ. good luck