Is this a proper rear end for MK IV?

[RCJones]

http://eastnc.craigslist.org/pts/5088484447.html

Saw this today and didn't know if it would work. Never considered IRS until this popped up while looking for a rear end. If this isn't viable then back to straight rear end

[CraigS]

I am far from an expert but I think that is a good donor. I hope others will chime in to say if I am correct.

[2bking]

This is what you need for the pumpkin , axles, hubs, and knuckles for the older IRS frames. The rest is not used. But if you haven't ordered your kit yet, I think the IRS now being used is the 2015 Mustang. I don't think FFR is making frames for the older models. Call FFR before you buy.

[edwardb]

That gnarly looking IRS assembly for $500 pretty much is why I've stayed out of the donor mode. You guys have more patience than me rehabbing that kind of thing. But to King's point regarding the changeover to the 2015 IRS setup. If you haven't ordered your kit and are just stockpiling parts, you probably need to reconsider using this vintage. What Dave said at the Open House was that Factory Five would honor all existing orders for kits with the older IRS, and they would support it for parts, etc. for the future. So I think they will be making it for a while yet. But it's certainly not open ended. Agree at some point only the newer 2015 setup will be available for new orders and builds.

[FFinisher]

Pretty sure that will have a 31 spline step. This will not work with ffr axles and will require custom axles that can be had.. But they are big $$. Offsetting any savings you may gain. Also spindles need to be from a t bird. Not sure if mustang spindles were the same .

I would stay away. Just my 2 cents

[RCJones]

Thanks for the replies, and yes I'm gathering parts. I'm starting to believe or understand that my "perfect combo" live axle rear end doesn't exist as a donor. Here it is: fox body width, 8.8, 5 lug, 3.27, disc brakes, posi / limited slip (I think they're the same in Ford land?) Please tell me there is a certain year/model I should be looking for.

[MPTech]

I believe you are correct, it doesn't exist as a donor. 3.27 W/Trac-Loc.
I bought all of the parts for the pumpkin separately (3.55 w/trac-loc) and had it assembled. Works great!

If you don't have your kit ordered yet, make sure they will still support the old IRS.