Let's see if I can get this worked out just in case I have any part of this wrong...
(T/F?) The Pinto and Bobcat from 1975 to 1978 did come stock with the 8" banjo rear axle (as an option?) with a 4x4.25 lug bolt pattern. What I'm trying to figure out for my '74 wagon is how to obtain an 8" for increased strength to replace the dinky 6.75 currently in there. Now the 71-77 Maverick axle is an option from what I see, but the 4x4.5 lug won't allow me to use the wheels I have. It also creates a problem for tire rotation unless I change the fronts to 4.5 as well, but I'd rather not do that. I'm at a crossroads right now whether to wait it out and find a stock 8" from a MII or Pinto or simply mount the Maverick axle on as is and add 1" spacers that change the pattern from 4x4.5 to 4x4.25.
Now if I do the latter I'm concerned about the wheels being hub centric instead of lug centric and if they have the strength to stay on. Imbalance at thigh speeds is a major concern. Something else I considered is simply replacing the axle shafts with something in a 4x4.25 profile, but I don't know if anything out there exists as an inexpensive swap option such as the fox 7.5 or 8.8 axles in a 28 spline. I also heard of simply having a machine shop weld up the old holes on the maverick axles, but that sounds like big money.
Am I overthinking this?
http://www.teufert.net/wheels/bolt-pat.htm
http://oregonhotrod.com/Rear%20Axle%20Measurements.htm
You seem to answer your own question. Between wanting to use your existing wheels, concern about being lug centric, tire rotation and (spare) and not spending a lot of money you simply need a Pinto/Mustang II 8" rearend. The other option of the Maverick 8" will be no easier to find either. As Archie Bunker use to say, "Case closed Edith."
It was a mostly a check to see if I had any part of my thinking wrong. The most cost effective and easiest solution for me at this time is to simply remove a Maverick axle (there are two in local yards), weld the old holes, and simply re-drill to 4x4.25 at a shop. The only problem left is that 1/2" in the track from front to rear. The cheapest solution to cure that is run 15mm spacers like those below and go over by .09 of an inch. Previously I made the mistake of thinking spacers didn't have a hub-centric lip, but this pair does. I also "think" that minor bit sticking out extra won't make a difference.
https://www.ebay.com/itm/2-15mm-Hubcentric-Wheel-Spacers-4x108-63-4mm-Hub-12x1-5-Studs/201921798339?hash=item2f037a20c3%3Ag%3AT5EAAOSwovNaBQIS%3Asc%3AUSPSPriorityFlatRateBox%2194551%21US%21-1&_sop=15&_sacat=0&_nkw=4x108+spacer&LH_BIN=1&_from=R40&rt=nc&LH_TitleDesc=0%7C0
If the 1/2" difference is not a problem for everyday use, then I won't bother with $25 spacers. I would go with them outright instead of welding the old holes on the axles, but for some reason nobody makes a 15mm spacer with the hub-centric lip in a 4x4.5 to 4x4.25 conversion.
In general, no it should not be an issue but do everything at your own risk. Wheel offset alone (with different wheels) often changes the relationship more than the 1/2" difference. And if I'm not mistaken the Maverick is 1/2" shorter. So that would offer more room for a wider (or more offset) wheel The only problem is it does puts the wheel that much closer to the rear spring so watch for that. Also, if I recall correctly the springs are not parallel. So measure at the front AND back for any clearance issues.
Oh, one other issue. When I went to an 8" (4X4.25) I got my rearend "drum to drum" out of a Mustang II. It was only $10 more and I'm glad I did. Even though the drums have a common stated diameter for the shoes..., the center hole of the drum was different 8" to 6-3/4". I mention this because I don't know if that becomes a hub centric problem for your wheels.
Three other things to check. One is the parking brake cable attachment at the backing plate and the length of the cable itself. The other is the yoke, that it will fit your driveshaft. Oh, and due note that the axle centerlne to the U-joint centerline is different on the 8". Therefore the driveshft might not fit. I was fortunate in that my C-4 / 6-3/4" to T-5 / 8" swap allowed the use of the same driveshaft! Lastly the spring pads on the Maverick rear might not line up properly with the Pinto springs.
Anyway, a lot more to consider than the1/2" width and bolt pattern. Hopefully someone who has done the swap will chime in. Traffic here is EXTREMELY light. Frankly it baffles me that we seem to get more people added as new members (noted as a "welcome" post) than we seem to get general activity on most days. So it may take some time before you get an answer..., or just proceed regardless.
Fantastic Witt and I really appreciate the help. I used to be into the SVO Mustang, XR4Ti, and NATO (Turbo coupe) crowd until California made it REALLY hard to play with any aftermarket performance on the OHC 2.3 and the Pinto is the only choice left to play with this engine without interference from C.A.R.B. in California. Anything after 1975 still requires a smog check in most counties and with the axle swap the turbo block won't be far behind.
I hear you. 73 Pinto wagon with 88 Turbo Coupe (stock) drivetrain here. Also six other cars 73 or older.
Quote from: Wittsend on July 23, 2018, 03:16:41 PM
I hear you. 73 Pinto wagon with 88 Turbo Coupe (stock) drivetrain here. Also six other cars 73 or older.
Fantastic setup! It's my hope to be where you are in the next six months, but I'll be fighting off a busy schedule.
One more question since it just popped in my head. Are the hubs (diameter) for the wheels on the 6.75, Maverick 8", Pinto 8", and MII 8" all the same?
Frankly I don't know. I assume you are talking about the hubcentric centering portion of the hub. I have (currently) Mustang II Rallye wheels on my car and as mentioned I have the Mustang II 8". I never did try the old, stock Pinto wheels and the 8". But like I mentioned about the center hole in the brake drum..., you never know. My expereience isn't "All Pinto," it is more limited to that which I have encountered.
Understood. Thanks though.
On the hub diameters, the 71-73 6.75" rears and steel wheels use a slightly smaller hub size than the later 6.75" & 8" rear and wheels. So 71-73 Pinto factory hub centric steel wheels will not fit on the 74-80 Pinto's larger hub.
If using the Maverick housing, I suspect the spring perch design is not the same and probably would need modification also. The Pinto/MII rears have a large oblong locating hole in the spring perch while the Maverick uses I believe a small round hole. Not sure if the spring perch is in the exact same location either. Not a big problem, just extra work. I seem to remember somebody else here describing their similar project in a thread with photos, a key word search might locate it.
Hmm...good to know. The more I look at the Maverick swap the less I like it. That MII/Pinto 8" is scarce around here, but I think I'll hold off till I can get my hands on the right axle rather then try to rework the Maverick rear. I'll see if I can find that writeup and if it's still feasible I'll look into giving it a try.
Hi Grocery Getter. I got in touch with the guy who is working on my 78 Bobcat to see if he has already put the 8in in which is replacing the 6.75in axle. Thought if he hadn't got it in yet, I may sell it to you. But it looks like he has it on the car already.
I bought the 8in from a kit car that originally came off a 76 Pinto the guy told me. It was his father's. I took the parts and the car to a guy who works out of his house. The car has been there since March, but it looks like he already has the leaf springs and the 8in on the car. He just needs to change the seal, hook up the differential, bleed the brakes, and may need to turn the drums.
Well, I still have the car listed in this forum for sale if interested. I haven't had any luck though. Maybe I'll just end up keeping it, and sell another car instead. Just trying to thin the herd.
Also, if you look in the Albuquerque Craiglist under car parts and under Pinto, you will find what looks to be an advertisement for a Pinto front suspension and in the background what appears to be a Pinto axle not specified.
Quote from: Lonny Candel on July 24, 2018, 06:45:11 PM
Also, if you look in the Albuquerque Craiglist under car parts and under Pinto, you will find what looks to be an advertisement for a Pinto front suspension and in the background what appears to be a Pinto axle not specified.
Good to know. It's worth a shot to send an E-mail.
Edit: Found the posting and...damn. It's a 6.75 rear. Thanks for the check though.
https://albuquerque.craigslist.org/pts/d/old-school-pinto-frt-end/6638531405.html
The Maverick axles would probably only need the access hole to be welded; the other three lugs could go between the existing ones.
Your only drop-in option is the Pinto/MII rear. Everything else will require fabrication and/or a wheel change.
Quote from: 65ShelbyClone on July 25, 2018, 09:32:10 PM
The Maverick axles would probably only need the access hole to be welded; the other three lugs could go between the existing ones.
Your only drop-in option is the Pinto/MII rear. Everything else will require fabrication and/or a wheel change.
Good news. I found a MII axle! It's a while away (Three hours :( ), but I've bribed my brother to go drive out and get it while I'm stuck at work Friday.
why do you feel the need to swap away from the 6.76" rear end?
Quote from: Srt on July 26, 2018, 12:36:23 AM
why do you feel the need to swap away from the 6.76" rear end?
1: I have a 2.3T in an '86 T-bird with a T-5 and wiring harness I'm going to swap in
2: I have a $200 (sale) Yukon part # YDGF8-28-SM trac loc unit.
3: I have a ring and pinion 4.11 set from a low miles 63 van
4: I have a dusty Holset HY35 in good shape
5: (https://memegenerator.net/img/instances/45501309/i-wanna-go-fast.jpg)
I think 4.11s are going to be awfully steep unless you stuff 28" tires under the back.
Quote from: 65ShelbyClone on July 26, 2018, 11:55:09 AM
I think 4.11s are going to be awfully steep unless you stuff 28" tires under the back.
Agreed. Drag cars (and maybe that is his intent???) run tall slicks and that effectively brings down something like a 4.11 ratio to be equal to say... (just guessing here) a 3.73-3.55 ratio with a standard street sized tire.
I've probably said it 100 times now but I wish there was an industry standard that factored the combined aspects of the rear ratio AND the tire circumference. It would need to be a 'feet traveled per stated number of engine revolutions' kind of standard. Too often I've seen posts where it is stated the person is going to use "this" tire or "that" ratio and the other aspect is not considered. But the reality is the tire circumference is ever bit as much effective as the actual gear ratio itself. Again this may be a drag car with tall slicks..., we just don't know.
That's kind of how I manually calculate RPM and MPH with respect to gearing. I find engine and tire RPM at 60mph and use that as a baseline. From there any changes are based on an equivalence ratio. It sounds convoluted, but only takes 10-20 seconds on a scientific calculator.
My main concern wasn't so much in cruising RPM though, but rather a potential delay in lighting off the Holset turbo due to the breif time spent in first and second gears.
Well now that we are on the subject of 8" rear ends , I am cleaning up my shed from extra stuff , I have new in the box 3.40 gears for a 8" never used , $125 , a set of 3.55 gears , they were used for 500 miles and removed to install 3.73s , and are in the box they came in , $100 , also a banjo 8" housing bare out of a pinto wagon , needs sandblasting , FREE if you pick it up , last is a new set of Zoom 4.11 gears for the 6.3/4 pinto rear , still in the org box , $125 ,
Quote from: 65ShelbyClone on July 26, 2018, 11:55:09 AM
I think 4.11s are going to be awfully steep unless you stuff 28" tires under the back.
The plan is to clean it up, replace all bearings, and use 205/60r13s. The only reason I have the spare carrier is my older brother gave it to me since he never used it in the Mustang he had fifteen years ago. He sold the car almost a decade back. It has the early 8" housing pattern with vertical supports. If 4.11 is too much then I won't bother.
BTW I had some help bring the axle home. Of course there's no tag to tell me what's inside. The rotation check doesn't work because I can't get a full turn. Something is jammed at a certain point.
Edit: I managed to get it loose. It's a 3.00:1. With the 4.03 first gear of the '86 T-5 I just might keep that R&P in there.
(http://i64.tinypic.com/2wc1zxt.jpg)
(http://i68.tinypic.com/5vuqko.jpg)
I had the 3.00 in my car. I actually liked the long time on boost between gears. It really made the car feel like it was P-U-L-L-I-N-G. The negative side was that at normal legal speeds on the street (25, 35, 45 etc.) there never seemed to be a correct gear. It was either too many RPM..., or too few RPM's at the next gear up. Maybe with 205-60-13's it will be slightly different. At that time I was running 215-60-14's. I'd say try it and see and then decide from there.
In as much as I harp all the time about tires being as much a part of the "ratio" as the gears if there was a rear gear for the street I'd say it was 3.25 as it relates to a ratio what Ford used (though it is very rare). The 6-3/4" has a 3.18. But with what was commonly available I'd opt for 3.40 and perhaps go with taller tires. I say all that with 13"tires in mine because i want to use the Rallye wheels. Frankly I need to get off my butt and mount up some 205-60-13" that I have. I keep saving them for my Tiger which has been on jackstands for 18 years now.
I get my tires in such an odd ways. I got three eccentially new Sumitumo 175-70-13" for $35 (all), two Sumitumo 205-60-13's for about $11 each and three Federal Formoza 205-60-13's for $10 each. I hate passing them up at those prices, but them I never seem to have a complete set. Oh the dilemmas of being a tight wad!
My tires are only 23.5" tall which I think is shorter than stock. That's probably helping me get away with the 3.00 gears, although I agree that 3.25s or 3.40s would probably be ideal.
The other thing is that at least with the stock setup (and I have the advantage of the '88 - 190 HP setup) is there isn't much after 4,500 RPM and for sure you shift before 5,500 RPM. The lower the gears (numerically higher) make that happen - quickly. It seems like lag.., spool rise, boost on-SHIFT. The feeling of power is very short. As I stated above the 3.00 allowed for that feel of PULLING. Faster? Who knows but I don't race my car, I just prefer to "feel" the fun.