8.8 fitment in 66?

PJx5x said:

so....

for a 65-66:
fox rearend with 99-04 rims


for a 67-70:
fox rearend with stock backspacing rims
or
94-98 rearend with 99-04 rims, possible 1/4 spacers needed?


....right?

Click to expand...

correct

Markus said:

Hello,
i use a 8.8 out from a 89GT fox in my 67. I use a 1 inch spacer with my 8 inch magnum 500 on the rear. I think the 8.8 will fit on your 66 without modification.

Markus

Click to expand...

Do you know the offest on your magnum 500's?

68GTCS said:

Do you know the offest on your magnum 500's?

Click to expand...

4.25" is most common.

hmmm

Could we condense the info here and put it in as a FAQ or Sticky??

It is useful info...and I would like to see a listing...

65 -66 use axle A do this, use these wheels
67-68 use axle A do this, use these wheels...

65-66 use axle B do this, use these wheels...

and so on...

maybe I am lazy, maybe I am just confused...

but putting stuff like this as FAQ or Sticky may eliminate the redundant threads...

Thanks...

i agree, thats why i tried to sum up the thread at the top of page 4

great post.

I have a question about welding in the spring perch tabs. How can I be certain that I have the pinion angle set correctly? In other words, how do I know that the positioning (rotation) of the perches is correct before I weld?

YLWRCR said:

great post.

I have a question about welding in the spring perch tabs. How can I be certain that I have the pinion angle set correctly? In other words, how do I know that the positioning (rotation) of the perches is correct before I weld?

Click to expand...

go to your local home depot and pick up an angle finder. It is magnetic and always points up. It will give you the degree amount from 90*.

The goal is to have your rear end parallel with the drivetrain angle. Put the angle finder on the crank pulley and get the angle. If the drivetrain is pointed down 2*, then you want your rear end to point up 2*. To measure the pinion angle, you put the angle finder on the pinion yoke where it u joint mates up.

Typically you want less than 3* of difference. So if your engine was pointing down 5*, you want your rear end between 2* up and 8* up. The less the difference the better. If you can match the 2* of the drivetrain (or whatever angle it is), the better. Dont forget though, this is all supposed to be measured at ride height. So if you have an extra pair of jack stands, jack up the leaf spings until they are holding the cars weight, then slide your rear end side to side to make it even and square. Then set the pinion angle.

Thank you for the feedback.

One more question...

"Put the angle finder on the crank pulley and get the angle. If the drivetrain is pointed down 2*, then you want your rear end to point up 2*. To measure the pinion angle, you put the angle finder on the pinion yoke where it u joint mates up."

So you are saying I am comparing the rearend flange angle to the crank pulley angle, instead of the rearend angle to the tailshaft angle?

I suppose the crank and the tailshift should be in line anyway.

Also, got a pic of an angle finder? I'd like to be sure I am hunting for the correct device.

correct?

YLWRCR said:

Thank you for the feedback.

One more question...

"Put the angle finder on the crank pulley and get the angle. If the drivetrain is pointed down 2*, then you want your rear end to point up 2*. To measure the pinion angle, you put the angle finder on the pinion yoke where it u joint mates up."

So you are saying I am comparing the rearend flange angle to the crank pulley angle, instead of the rearend angle to the tailshaft angle?

I suppose the crank and the tailshift should be in line anyway.

Also, got a pic of an angle finder? I'd like to be sure I am hunting for the correct device.

correct?

Click to expand...

Correct... The crank pulley is exactly 90* from the driveline angle (tailshaft angle). The problem with using the tailshaft angle is the casing is a cone and will give you the incorrect angle. Here is picture on what it should look like:
View attachment 299471

Using the crank pulley will give you the perpendicular angle to the driveline angle. Using the pinion yoke (rotated to give you an up and down angle) will give you the same perpendicular angle. Compare the two

Excellent, thanks for the help.

Last thing... when it comes to actually positioning the leaf spring tabs prior to welding, how do you recommend I go about this?

Should I position the rear over the leafs and jack it up to ride height, make my measurements, and then tack them in place?

I am worried about taking the measurements when the car is not at ride height.

I guess what I am asking is, is the pinion angle a function of ride height?

I don't want to weld the tabs up with the suspension unloaded, and then find that the pinion angle changed after loading/welding.

I think the easiest way would be put the perch on the leaf springs, then put the rear end on top of that. Point the pinion down a few degrees and tighten up the u-bolts that hold the rear end in place. Jack up the rear end to ride height (basically when the car comes off the jackstands, and put teh jackstands under the rear end tubes. Let the jack down and put the jack under the joke area. Use the jack to raise up the yoke end until you get the desired pinion angle. The ubolts should be kinda tight but you should still be able to change the angle. Just go slow so you dont have to find a way to bring the pinion angle back down without starting over.

Perfect. Exactly what I had in mind.

Thank you for the help sir.

Info

Just joined up after reading this post.
Just letting you guys know, I just finished a 67 conversion, everything out of a 90Gt, I will post some pics, but back on topic, a 8.8 out of a 87-93 mustang will work with no mods other than cutting the old suspension brackets of and installing the spring perches from original rear, the 8.8 was @1" longer than the original.

xoxbxfx said:

Thats correct, but thats what im sayin... fox - 99+ is 3" diff.... 94-98 is 1.5 shorter and fox is 1.5 shorter than that.

Click to expand...

This is the list I have Compiled. This is width flange to flange.

Year|Mustang|Cougar|Commet|Granada|Ranger|Explorer|Aerostar|cown_vck|T-Bird_|
____|_______|______|______|Monarch|______|________|________|________|_______|
1965|57.25__|______|______|_______|______|________|________|________|_______|
1966|57.25__|______|______|_______|______|________|________|________|_______|
1967|59.25__|60____|59.25_|_______|______|________|________|________|_______|
1968|59.25__|59.25_|59.25_|_______|______|________|________|________|_______|
1969|59.25__|59.25_|59.25_|_______|______|________|________|________|_______|
1970|59.25__|59.25_|59.25_|_______|______|________|________|________|_______|
1971|61.25__|59.25_|59.25_|_______|______|________|________|________|_______|
1972|61.25__|______|______|_______|______|________|________|________|_______|
1973|61.25__|______|______|_______|______|________|________|________|_______|
1974|_______|______|______|_______|______|________|________|________|_______|
1975|_______|______|______|58_____|______|________|________|________|_______|
1976|_______|______|______|58_____|______|________|________|________|_______|
1977|_______|______|______|58_____|______|________|________|________|_______|
1978|_______|______|______|58_____|______|________|________|________|_______|
1979|_______|______|______|58_____|______|________|________|62.8____|_______|
1980|_______|______|______|58_____|______|________|________|62.8____|_______|
1981|_______|______|______|_______|______|________|________|62.8____|_______|
1982|_______|______|______|_______|______|________|________|62.8____|_______|
1983|_______|______|______|_______|______|________|________|62.8____|_______|
1984|_______|______|______|_______|______|________|________|62.8____|_______|
1985|_______|______|______|_______|______|________|________|62.8____|_______|
1986|58.75__|______|______|_______|______|________|________|62.8____|_______|
1987|58.75__|______|______|_______|______|________|________|62.8____|_______|
1988|58.75__|______|______|_______|______|________|________|62.8____|_______|
1989|58.75__|______|______|_______|______|________|________|62.8____|_______|
1990|58.75__|______|______|_______|58.75_|________|59.75___|62.8____|_______|
1991|58.75__|______|______|_______|58.75_|________|59.75___|62.8____|_______|
1992|58.75__|______|______|_______|58.75_|________|59.75___|62.8____|_______|
1993|58.75__|______|______|_______|58.75_|________|59.75___|62.8____|_______|
1994|60.25__|______|______|_______|58.75_|59.75___|59.75___|62.8____|_______|
1995|60.25__|______|______|_______|58.75_|59.75___|59.75___|62.8____|_______|
1996|60.25__|______|______|_______|58.75_|59.75___|________|62.8____|_______|
1997|60.25__|______|______|_______|58.75_|59.75___|________|62.8____|_______|
1998|60.25__|______|______|_______|______|59.75___|________|62.8____|_______|
1999|61.0625|______|______|_______|______|59.75___|________|62.8____|_______|
2000|61.0625|______|______|_______|______|59.75___|________|62.8____|_______|
2001|61.0625|______|______|_______|______|59.75___|________|62.8____|_______|
2002|61.0625|______|______|_______|______|59.75___|________|62.8____|_______|
2003|61.0625|______|______|_______|______|59.75___|________|________|_______|
2004|61.0625|______|______|_______|______|________|________|________|_______|

Wow, I was looking for a thread like this last week. Finally found it in reference to a new thread.

Maybe this should be a tech sticky?

lots of info here to sort out...some accurate, some not...

fyi the explorer rear is the exact same width of teh 67-70 rears...so if you leave the offset pumpkin and don't shorten it, it's perfect with 67+ cars

the explorer rear is the exact same width of the fox rear too.....in a 65/66 car both the explorer and fox rear will stick out 1" more on either side, which is perfect if you're using sn95 fox bullit style wheels.


as for pinion angle, I've been doing a ton of research...and from what I've read, it's good to have a 2 degree difference, and not be exactly parallel. As well, you have to account for rear end wrap...when you're accelerating and even cruising, your rear is gonna wrap up. If u go up 3 degrees on your rear, and your engine is 3 down, then when you drive, your angles will be way off. I've heard, for example if your engine is 3 degrees down, then set your rear at -1 down as well...this way when you start moving, the rear end will come up and level out, and still have the 2 degree difference necessary.

I haven't welded up my perches yet, but can anyone comment on this?

Ok so i have 1 65 coupe that i am going to be putting 18x10 FR500's on. I have an 87-93 4 lug fox rearend, i want to run the 11.65" cobra brake setup and obviously convert to 5 lug. The car has been mini tubbed so tire clearance is not an issue on the frame side but i need to know how much i need to narrow my rearend for when its setup with the disc brakes. Thanks in advance