Doing a 4 to 5 lug conversion on my 66 mustang. She has a 67 8 inch rear and am installing 67 spindles on the front. Will I have trouble with wheel track or steering geometry doing this?

 

Yes, on both counts.

Why are you doing this conversion?

 

It's a v8 conversion. 289 was already installed. The rear was already replaced. It was a six cylinder but the rear is a 5 lug and the front was a four lug with six cylinder suspension. It's either put a v8 suspension on it or have a squirrely riding car with two spare tires.

 

Well, your rear axle is too wide for the 66 body, requiring rear wheels with 1" more offset than the front wheels, so your spare tire problem still exists.

67 spindles will have different steering arm geometry than 65-66, and will require 67-69 outer tie rod ends. It will work, but steep turns a low speed, such as maneuvering in parking lots, will have the front tires squalling with misalignment when the wheels are sharply turned. Not fatal, but correct 65-66 spindles are easily acquired, so why bother with the 67's?

 

They are what were available. I know about the tie rod ends already and the rear was already in the car. It's what I have to work with. Finding 66 spindles has been an exercise in futility. Seems there are none to be found and I found the 67 spindles on ebay. C60A spindles. Figured I already had 67 rear so might as well use 67 spindles on the front. I have 14 inch wheels that will fit front and back. I think they came off of a 67 as well.

 

'65/'66 V8 spindles show up in the Parts For Sale forum on this website regularly. Did you look there?

 

It's not what you want to hear but 22GT is right. Any job worth doing is worth doing right. Handling is not something you want to "wing" and your '66 deserves better. I'd keep looking for '66 spindles and I'd figure out how to get the correct rear end in her. It's gonna cost money but it's money well spent.

 

Forum members could do a better job helping you if we knew where you're at. For example, I've seen two 8" rears on CL locally (NJ) over the past couple of weeks. One looked particularly nice. I have a custom built 9" rear so I didn't pursue them beyond scanning the posts.

 

Dogman, perhaps post your location in your BIO.


NO guarantees but I have a friend in MA that has 4 barns full of 65-69 parts. He's been collecting parts for ~ 20 yrs, selling parts a hobby.
Send me a PM if interested and I'll give you his number.

 

Bad choice of a rear end for your car.

 

Post a wanted ad in the Mustang Want Ads section of this forum.

 

Yes, put down where you live. There are still a lot of parts out there it just takes a little longer finding them.

On the spindles, yes they are different but it's been done. The front suspension on my 66 is been modified quite a bit. I had a question about the geometry on later spindles. I spoke with Dennis who owns CSRP and is a member here. The difference between the spindles is that the later spindles have .500" less offset in the top top bottom on the tie rod arms. The later tie rod arms are flatter. The angle of the arms are the same. Dennis's company manufactures disk brake kits for our Mustangs. All the parts are brand new and even makes new spindles with the correct geometry for the 65-66 cars.

The 70 and later spindles are quite common to be used Mustangs including the 65-66 in racing and street because they are a lot stronger. On my car I was having issues even with my stock spindles. I now have 72 spindles with disc brakes along with a bumpsteer kit. My car drives fine. Even adding caster will help. Each degree of caster lowers the tie rod about .100" closer to stock 66 tie rod location.

 

You are really making your life difficult with the mixmatching of parts from different years of mustangs. My advice is to put the correct year parts on your car. The 67 rear in your 66 is not correct, but will work. As for the front end...stay w/ correct spindles, so you can order the correct disc kit. Trade/sell what you have that is not correct and get the correct stuff. If you are still determined to do it with "what you have on hand", you will be re-doing it again in the future as you will not be pleased with your results.

As to your questions about wheel track, normally the front tire track is wider than the rear, so the backend of the car "follows" the front end, making steering/cornering easier. With the wider rear, you are disrupting this. It's not the end of the world, but could be better. That is why you are doing these mods...to make the car better to drive and enjoy?

As for geometry...the wrong spindles with the incorrect steering gear (idler, center link, tie rods,) will not work as it was intended to do, this could effect your ability to steer w/o wandering or getting squirrelly over bumps and whoop-to-doos. It's your car, and your call, but if you ask us, we'll tell you what we think. Again, this is MY opinion, others may have a different opinion.

 

I appreciate all of the responses here. To answer some of the questions the rear end is what was on the car when I bought it. It's been a puzzle from day one. I really wish it had been left stock but that ship has sailed and this is now my nightmare. I would really love to find the correct spindles but I think I might be screwed on the rear end. Panhandle of texas is where I am and yes I'm looking for the proper rear end and maybe I'll get lucky at the swap meet next month. It's just what ive got to work with at present. There's still lots of work to be done on this car though and I've got nothing but time on my hands. As far as the spindles are concerned I'll keep looking I guess. They are REALLY hard to find and personally I think 450 dollars for a set of spindles is outrageous. Especially when you dont know who you are buying from or whether they know what they have. I really don't want something to "work". I'd rather have it right without issues later.

 

I have a '65 8" rear end in Lampasas which is 6 to 8 hours away depending upon where in the Panhandle you are located. Do you ever come to Austin?
I'd trade you my housing and axles for yours. Keep your pumpkin and brakes.

 

here's some spindles.

V8 spindles 1965 1966 mustang

 

If you were closer to Kentucky I would talk some business with you on some 65 parts.

 

FYI, that rear axle is just about the perfect width if you ran 99 to 04 17" wheels on your 66. You would have to run 1" spacers in front. The other good thing about it is the center section. It should have the "waffle" pattern on it which makes it stronger then the 65 and 66 centers. It's the preferable unit.

 

1965-66 Ford Mustang suspension
Maybe he'll sell the spindles separately?

 

Those are not 65-66 spindles. Take a good look, disc brake spindles.

 

Ford Mustang 1965/66 Disc Brake Rearend
Probably more than you want to spend...

 

have you considered using a late model 8.8 rear? they may be just as wide as what you already have in the 8 inch, so may not address the problem, but you get alot for cheap.

Ford Mustang 8.8 rearend GT 95 Disc brakes 1967 67 66 65
Ford 8.8 31 spline axles w/disc brakes

 

Alternatively, you could go with
QUICK PERFORMANCE 66 MUSTANG 9" SM BEARING 31-SPL AXLE PKG (about $765 shipped) and another $400-$500 for a rebuilt 3rd member.
QP FORD 1965-1966 MUSTANG 9 Inch Housing & Axle Package

 

If you are in the Pan Handle, I would contact Mustangerbob1 here on the forum. He is here in the Dallas area so at least the shipping might not be as bad. I have bought some pieces from him and he has always been fair and upfront with his descriptions and prices.

 

Dagnabbit! NOW I see what you mean and now that you point it out, it seems obvious. Thanks for cluing me in. I'm sure that this is useful to others too.

 

I just measured the rear end on this mustang and it measures 52 and 1/2 inches back plate to back plate. I appreciate all of the help here. I'm gonna check on the spindles. You guys are great! I'm not gonna make this car unsafe to drive. I'm not gonna use those 67 spindles I bought from ebay. I just would not feel safe with those now that I checked here. Valuable information for sure!

 

Maybe I can sell these spindles on craigslist or maybe at the swap meet next month. I already ordered the 67 outer tie rod ends. I checked csrp and they have a disc brake kit for 65 to 66 that not only has the spindles but the dual bowl master which is on my list of upgrades. One of the reasons I'm redoing the front is because the front drum wheel cylinders are no good and I want disc brakes on the front anyway. I found a guy on ebay that sells a kit to make your 4 lug to a five lug with the existing i6 steering but someone already put the 289 in my project and didn't bother to upgrade the front suspension to carry the v8. To tell the truth I wouldn't even consider using that kit without upgrading the steering for a v8. I just want it right without problems later.