57" 71-74 V-8 Mavericks 8", All '75-77 6's & 8's Maverick 5 Lug 8", 49-51 Ford, 57-59 Ford 9", 58" 78-88 Mid sized GM Car, Malibu/Monte Carlo (82 up Metric Studs), 80 Granada & Lincoln Versailles, 67-70 Mustang/Cougar/Fairlane, Regal with 10 bolt axle, S-10 P.U., 65-67 Nova, 60" 55-64 Chevy Car, 67-69 Camaro, 64-67 Chevelle, 68-74 Nova, 71-73 Mustang/Cougar, 84-95 Corvette, 60-61" 64-69 1/2 ton 2wd Chevy/ Some GMC 6 lug rear end 12 bolt Coil spring set up Possible gear ratio's 3.70. 0000000716 00000 n Newest [ January 23, 2023 ] Vintage 1980 Yamaha Enticer Snowmobile Revival to Former Glory Roadkill Powersports Like the 8.2-inch 10-bolt, the 8.5 10-bolts use C-clips to retain the axles. some sources state that the 67 and latter are wider. NFTs Simplified > Uncategorized > pontiac rear end width chart. '70's Ford Grenada For a better experience, please enable JavaScript in your browser before proceeding. "+j)(4 T "Hd&6F T:R%xA+R>6^yyp0}Zc9^):(cdf_rKr2zB,ywV}w0*lkxwM y icR,2*G{>K\"|>XWAIRYQ_dKx}wt}_=/3=)>fQaa-# C+|prj~%ox$LpKaGPG&T`o. If it has the original Borg Warner posi then it is stronger than the Chevy 10 bolt. Actual wheel track could be as much as 6" to 8"depending on drum size: '67 to '70 Mustang/Cougar 6 cyl. 1990 to 1992: 7.625 inch ring gear, 28 spline axle. Find 1967 PONTIAC GTO Differential & Rear-End Components and get Free Shipping on Orders Over $99 at Summit Racing! Understanding Aluminum Heads and Spark Plugs, OK Go Needing/Getting ~ Its All In The Timing, An Online Magazine for DIY Hot Rod Builders. June 5, 2022 Posted by: Category: Uncategorized Fabcraft can also supply an excellent manual that tells you everything you need to know about these rearends, along with instructions on overhauling them, or they'll refurbish a rearend for you. If in doubt, consult one of our differential experts at (800)510-0950! Roadkill Customs has evolved from local hot rod shop to online how-to magazine for budget-minded do-it-yourself hot rod builders and enthusiasts. . '70 Duster , '71-77 Maverick They're tough, right? Very hard to find set, being as this is version is not being reproduced. Learn more. It may not display this or other websites correctly. i've seen that link about a hundred times now and it's kind of funny how the 73-77 GM A-body is not included. 1957-58 are 29-spline and 1959-1964 are 31 spline. '69 Nova Vintage 1980 Yamaha Enticer Snowmobile Revival to Former Glory. Outside Width: Year: Model: 56.50: 1969-1977: Maverick 8" 56.50: 1990-1992: Ford Ranger 8.8" 56.75: 1995-2003: Ford Explorer 8.8" Narrowed w/2 short side axles: 57.00: 1974-1978: Mustang II 8" 57.25: 1957-1959: Ford, Ranchero . Bigger engines introduced in both Oldsmobiles and Pontiacs for 1959 prompted the second generation of these rearends with 31-spline axles, which were reportedly 22 percent stronger than the previously used 29-spline shafts. My '64's measure 54.25". 1982-1997. This number may be on the top, bottom, or either side of the axle shaft. I've heard 'prolly torque-tube' from most that I've asked My friend's stock '41 Pontiac is open drive, so I would imagine that the '50 is as well. Posts: 8. You can identify the B-O-P assemblies by the two reverse-scalloped sections of the differential cover located at the 9 and 3 o'clock positions. What I did is shown below in the photos. Other changes were made to the limited-slip carrier, but strength was not adversely affected. |;|tB70t:`!t;?Yp?o^16Y*Ra(k ;6te64^bv n+;:G57@hbM_5 N Interest in vintage drag racing is now approaching a rapid boil. With perhaps less than 10 percent of Pontiac and Oldsmobile fullsize cars possessing the Safe-T-Track and Anti-Spin options, prices for unmolested examples remained high. . A: Extremely strong! Thanks to the efforts of the Fabcraft Metalworks crew all the parts necessary to rebuild one are available along with a selection of improved components and special tools to make working on them easier. B-O-P axles also have identifying grooves traveling along each side of . & Conditions, Ford Mustang II/Pinto & Mercury Capri/Bobcat, Monte Carlo, Regal, etc. Once I had the wooden rear end made I attached the wheels to the small wood axle flanges with wood screws and large washers to stop the screws from pulling through the lug nut holes. 455 ho only(c-type axle) 12 bolt 1970 3.36 cok col fb 1970 3.55 cow cox fb 1970 3.55 wv xv gto 455 ho only(c-type axle) 12 . I placed the order with Speedway motors in late July for my rear end housing and Currie axles. This information will change as further information and corrections become available. '72 Cougar, '74 Pontiac '49 Plymouth, '61 Chevrolet Impala '65 Cadillac, '66 Buick Wildcat '66-67 Chevrolet Big Car, '72 Charger 2D reg-duty / 4D med-duty 4-pinion. I'm running the wider blazer rear end . 0000002277 00000 n '72 Chrysler. 1967 Pontiac GTO - Wheel & Tire Sizes, PCD, Offset and Rims specs | Wheel-Size.com. Advance Design Trucks seem to be using rear What is the width of a 1959 pontiac rear end? The 1' wider that was stated in paul/chuck 's book may have been miss spoke. We provide how-to and technical articles, vehicle and build features and examples, plus calculators and lookups that will help you get your ride from dream to driver. Buy in monthly payments with Affirm on orders over $50. Axle Images: Axle Details. Both of these are semi-floating axles. GM quit making the 9.3-inch in 1964. 1958-1970 Chevy Rear Differential code Identification : Using the charts below, you will be able to learn alot about the rear differential in your classic full size Chevy. With its larger bearings, larger gears, and larger axles, the P/O 9.3 would fall somewhere between the Ford 9-inch and the Dana 60 in terms of strength. find the 1/2 ton size yoke on a dana 60. Privacy Policy. I am using a 62' Olds rear in my 61' Bel Air and it is 1" wider that the stock Bel Air rear. I have a source for the axleshafts and the difference in the shafts shows this to be true, BUT doesn't show the diff center . Good luck. 1310 yoke, Dana 60 used the heavy duty yoke which takes the larger 1350 yoke. Last Update: Feb. 24, 2023, 5:12 a.m. It's not to the same level as a concours-correct restoration; no judge will deduct points for an incorrect paint code. Forbes and various locations throughout the Web and Automotive Magazines. Approximate rear end widths measured from backing 1939 engine numbers run 1915447 through 2697267. Automotive Technical and Reference Information, Project Cars, Trucks and Salvage Vehicles For Sale. 3:08, 3:40, 3:73 "Stovebolt" Specifications. There is no point in mocking up the wheels to a width that in not commercially available or one that was never provided by the OEMs unless you are planning on spending a lot more money on a custom width housing and axles. manufactured by Pontiac in United States. Ford Mustang Complete 9" Rear End Packages, GM G-body 78-87 Complete 9" Rear End Package, GM Chevy S10 82-04 Complete 9" Rear End Package, GM Tri 5 55-57 Chevy Complete 9" Rear End Package, GM X-Body Nova Complete Rear End Packages, Axle Bearings, Retainer Plates, & Wheel Studs, Bearings, Differential Parts, Seals, & Hardware, Master Cylinders, Caliper Kits, and Parts. Look at the RPO codes. 4.24 out of 5 stars. 0 This 1955 Chevrolet 3100 Step Side Pickup Truck was built by the Hot Rod Factory, Minnesotas premier hot rod shop and muscle car restoration facility. Find your GMC/Chevy vehicle in the chart below and click on the illustration for a larger view. Fabcraft also offered complete components for the differential, including all necessary bearings, seals, shims, limited-slip clutches, solid spacers, and crush sleeves, as well as beautifully refurbished OE parts. (painful to me while driving) I am pretty sure that it is the standard BOP 8.2, 10 bolt. 0000006915 00000 n Someone may correct me, but as I recall 1959 was the first year for the "Wide Track" Pontiac. In searching the web I found the following links that have a massive of information on rear end widths and wanted to share. I'm not sure of the Task Force width ranges at this time. And yet, all too often, a beautiful gasser built today is sitting on top of a Ford 9-inch axle. Your differential is the set of gears that allows your vehicles driven wheels to revolve at different speeds by splitting your engine torque in two directions, An Online Magazine for DIY Hot Rod Builders. pontiac rear end decoder year ratio open posi model notes: . . Lincoln Versailles, Regal with 10 bolt axle, S-10 P.U., 65-67 Nova. Diagram. Mickey Thompson even produced aftermarket Olds and Pontiac magnesium gear cases that were frequently used in dragsters. Is a pontiac center section as olds rear ends of that era? Once I had determined the desired width with the loose wheels and tape measure I constructed a wood rear end out of a 2x4. Prices and availability are subject '67 Mustang V-8, '69 Firebird I cut two axle flanges from a couple of short pieces of wood and then used 3/8 lag bolts to attach them to the longer center portion of the rear axle. Outside of flange to outside 54.25" 66 up are wider. Richmond Gear calls the 57-64 Olds/Pontiac rear a GM 9.3" Axle (the ring gear is 9.3 inches). '73 Ventura, '65 Ram American Building an example that truly reflects what was around back then takes a certain passion for correctness. "SPECIAL" CARS - 1938 Pontiac Special six. '55 -57 Chevrolet, 68-69 Fair lane 6 or 8 Many Ford 9-inch parts are made offshore; they have smaller bearings and smaller diameter gears requiring less material. The two makes used very similar differentials through the mid-'40s and into the '50s. GMC V-6 used a 3.21 Dana 44 used a standard chevy 1310 yoke, Dana 60 used the heavy duty yoke which takes the larger 1350 yoke. Many aftermarket options exist with all of the appropriate mount points. Dec 26, 2008. '72 Cricket This assembly used an 8.2-inch ring gear diameter and 28-spline axles for Camaros, Chevelles, Impalas and even the early Chevy II's. 60" 60's GMC and ends with widths ranging from 58"- 62". Approximate rear end widths measured from backing plate to backing plate. SKU: CE-GMG7887X. The Dana rear end is a bolt in swap for the both the 8 3/8 and the 9 1/4, all rear ends can be had with the same size u joint yokes, vans are good place to. Snap On vs Daytona, Pittsburgh, ESCO, Husky, More. Another factor that made these rearends popular was the wide selection of factory gear ratios available, 2.56:1 through 4.30:1 while even lower drag racing cogs were available from aftermarket suppliers. No one is making new 31-spline side gears at this time, which is not good. By designing ring-and-pinion sets to fit the previously less-attractive, but more available, Series II OE carriers, performance ratios could now be utilized without the need for an unfavorable ring-gear spacer. [ July 26, 2022 ] Reversing Gears ~ Rescuing One's Own Derelict 1967 Pontiac GTO Builds and Examples [ July 24, 2022 ] . I believe the width, outside axle flange to outside axle flange, is 64 inches. A turbocharger was added to the 301 to give the 1980 Trans Am an injection of performance. The new 9.3-inch provided outstanding durability when subjected to abuse from all classes of race cars, including Top Fuel. Pontiac/Olds 9.3 parts are manufactured in the United States and are made in smaller custom production runs using high-quality alloys and the best materials available. The following tags will show a 4L80E transmission as an example. 0000000991 00000 n 70 2wd 6 lug rear end 12 bolt Possible gear ratio's 3:08, 3:40, 3:73 70-81 4wd 6 lug reared 71- Newer 2wd trucks use a 5 on 5 lug pattern 71-76 Full Size Cars " "" "" ". http://www.jalopyjournal.com/forum/showthread.php?t=128884, http://www.jalopyjournal.com/forum/showthread.php?t=38805, Upstate New York, watching my New Yorker Rust, http://www.jalopyjournal.com/forum/showthread.php?t=128884&page=2, http://www.jalopyjournal.com/forum/showthread.php?p=1450810#post1450810, (You must log in or sign up to reply here. 3.08. The intake valve size increased to 2.11" and the exhaust valve increased to 1.77"in size from the previous model. '69 Javelin Six , '70 dodge '66-67 Chevrolet Big Car, '72 Charger Under the hood, Pontiac installed a 2.5 . GM with 7.5 & 7.625 Ring Gears : 1985-1997. Several features are common to most gassers. Prices and availability are subject 0000007740 00000 n My 69 gto convert., purchased within the last year has a painful 2.56 rear gear. A solid front axle was found under the front of nearly every gasser. } 70 2wd 6 lug rear end 12 bolt Possible gear ratio's Engine Numbers. Vehicle. Cars from all the traditional drag racing classes are being built and/or restored, but among the most popular of these period-correct builds are the cars riding high on solid front axles and sporting fenderwell headers: gassers. ?|-Zce14^nF%67( }fSRaQfqX?|{8{>? VX5EX=b :"-'k>.VbyV^-nWxv-WgUtpo>sMhlI4ZV<4+s>|2k>\x{7M^^x. The Borg-Warner HD rear end was dropped and replaced with the old 7.625 (7 5/8) inch rear end. A period gasser can be built by scrounging swap meets, salvage yards, and the Internet for many of the components necessary to complete a genuine example of one of the dominant race cars from the 1950s, '60s and '70s. The P/O rearend and parts were getting harder to find and there were more Ford 9-inchers being made every day. may be different than pictured. The 8.5-inch 10-bolt rearends have ten 3/4-inch hex head bolts with 7/16-20-inch left-hand thread bolts that hold the ring gear to the carrier. In the '50s and '60s the search for high-performance parts usually meant a trip to the wrecking yard to rob components, engines, out of big, powerful cars of the dayChryslers, Fords, Cadillacs, Olds, Pontiacs, and W-Chevys were all used. As the popularity of the Ford 9-inch increased the P/O 9.3 began to fade from the scene. GM 7.75" (Australian - Some 3rd Gen Camaro/Firebirds) GM 8.0" - Rear - Late Model Midsize Truck Ring Gear Diameter: 7.75" Ring Gear Diameter: 8.0" Pinion Diameter / Spline: 27 Pinion Diameter / Spline: 1.781" / 27 Ring Gear Bolts: (8) Ring Gear Bolts: (10) 7/16"x20 LH Cover Bolts: 9 Cover Bolts: 10 Carrier Breaks: 2.77 / 3.27 Carrier Breaks: None In head/2 per cylinder. Add Width to compensate for drums as follows: 4" - 5" for small cars 5" - 6" for intermediate cars 6" - 8" for large cars . 2/4-door sedan body type. Click the above picture to view full size. '62 Buick Skylark, '67 Chevrolet Six Real World Hagerty Collector Car Insurance Claim Experience, How To Be Prepared For A Dyno Session And Not Waste Your Money, Holey Goat Father/Son Texas Road Trip 5 Days, and 2000+ Miles, Are You Killing The Hot Rod Community? If you would like to compare the fit with a couple of different widths build your wooden rear end for the narrower width and then add shims to the ends to change the width. 66-69 axle does not include 64 65 . Because OE components were still widely used in racing circles, the 9-inch gained traction as a viable alternative, superior to the newer, cheapened, integral-style axles using C-clips and flimsy internals. '71 Comet , '71- 72 Pinto, '39 -48 Chevrolet, '68 GTO Discussion in 'Traditional Hot Rods' started by Ruiner, Sep 4, 2006. 59" 68-83 Corvette , 67-70 Mustang/Cougar/Fairlane, 60" 55-64 Chevy '68 AMX 57" 71-74 V-8 GU2 - 2.73's Standard auto trans gear ratio. While not as strong as a race-dedicated spool, the 31-spline Trophy Track carries a potent arsenal, including six 9310 alloy gears and twin cross-shafts, all of which are dimensionally larger and stronger than anything offered previously. They are also easily modified to suit any chassis. They were tough with 9.3-inch ring gears, big pinion shafts, and large-diameter bearings and tough axles. plate to backing plate. These dimensions do not include brake drums and are measured from backing plate to backing plate. Needle BUILD IT YOURSELF - PARTS LISTS BUSHINGS TO ADAPT TUBE SIZE . Rusty but Rare 1976 Chevy K10 Sport Truck Revival! 62" 64-77 Chevelle, 73-76 Torino, 89 note 64 64 axle is same. But it's been so long I can't be certain. Ford continued cranking out the 9-inch in vast quantities well into the '80s. Picture is from parts book. HVMo0WJ~H|V`-e)6`!$)=-~6x@h1|o Jeremy. GU5 - 3.23's Optional auto trans gear ratio. How to cut your Ford F100 long bed to short bed in a weekend DIY project ~ Two-Part video details cutting frame and bed. getting back to the differential, why bill didn't cover 1956 i don't know, might have just been a typo or overlooked. Vehicles with Similar . My rear is the bolt in axles. Today finding a P/O 9.3 may take some searching and it's helpful to know what to look for. These smaller volumes and domestic content result in slightly higher prices. It has been my experience that the 66 up axle is longer. The high-volume production runs of Ford-9 inch components allow them to be relatively inexpensive. '64 1/2-'65 Mustang Calculating the torque multiplication that your axle gears provide is quite easy. Since then, it has become the mecca of Pontiac technical data and knowledge that no other place can surpass. I have in the past struggled to measure the car for the correct rear end width to get the wheels and tires to fit correctly for both appearance and to avoid contact with the fenders, frame and suspension. A little history: In 1957, three important axles were introduced: Ford's 9-inch, Chrysler's 8.75-inch, and GM's 9.3-inch Hotchkiss-style axle for Pontiac and Oldsmobile. Some of the most frequently asked questions regarding the Pontiac/Oldsmobile 9.3-inch rearend: A: Fabcraft Metalworks provides virtually every component for the Pontiac/Oldsmobile 9.3-inch rearend. If you would like to compare the fit with a couple of different widths build your wooden rear end for the narrower width and then add shims to the ends to change the width. '67 Chevrolet big car You can do this by multiplying by the gear ratio. Year. Billet-steel yokes and carrier caps could be added to make the 9.3-inch nearly bomb-proof. Approximate rear end widths measured from backing plate to backing plate. 0000005198 00000 n var I=new Image(1,1); I.src=u; 60" 60's GMC and some Chevy's Dana 44 or Dana 60 with leaf springs 6 lug, Gear ratio's 3.21 to 3.92. '67 to '70 Mustang/Cougar 8 cyl. Post: rear end width chart (Topic#173541) greg pharr Contributor Posts: 897 Loc: North Mississippi Reg: 07-09-03. GMC V-6 the versailles / granada rear ends from flange to flange is 58.5". Suspension Width (Flange to Flange), Ford Mustang II/Pinto & Part Number: YGA-21289. Numerous e-mails and phone calls, stories of lost and found axles finally resulted in an e-mail from Speedway motors November 22nd apologizing for not handling this order in a timely manner and that a refund would be sent today. Is a pontiac center section as olds rear ends of that era? hi don, there is no major difference in the pontiac differential from 1949 to 1956 other than rear brake related parts. 0000006068 00000 n The now famous Ford 9-inch, with it's unique, straddle mounted pinion, offered great strength for its weight, but even the heavy-duty nodular-iron version suffered from weaknesses that the 9.3-inch did not. I'm sorry if I repeated what I've learned to accept as fact, but there are other reasons besides what I've read that have convinced me that '64/'65 housings are narrower than the '66/'67. 6>"FlJz^l,*4&V0afw .a@z"PXdj}o`2/ OQs=`&qf aDK|/U32.)0i%q~P"BaLw.Y@`uwy#Do~vt*o~@$y-KZe]X3q'WWb2y)0`61"4@Q*`6k RPf\`H#@ ^M8-|&YxO-t Why not a Ford? Snap On vs Daytona, Pittsburgh, ESCO, Husky, More. The current axle needs to be measured to verify width, because it plays an important part in determining what rim backspacing is necessary. The non C-clip 8.5" 10 bolt, type "C" rearend was used in some 1969-'72 Pontiac GP and 1970-'72 Monte Carlo. On Gen1, the code is "hit" on the right side of the rear axle (passenger side) with the inscriptions facing the front of . '72-75 Datsun Pickup I guess 66 will work too, but I don't have any way to verify this, nor any more information for you. Copyright 2023 Welcome To Rodplans! $5 Off Your $100 Mobile App Purchase . The 1967 GTO came in 3 speed Automatic and a 4 Speed manual. 0000008567 00000 n The most common GM unit for the 1982 to 1992 Camaro is the Saginaw style 10 bolt Chevy differential. Contributing information were Bob Welch, J Forbes and various locations throughout the Web and Automotive Magazines. I came up with a cheap simple method to confirm the results of the measurement taken with the loose wheels. In this 489 case it is 3:91 gears and a 1 7/8 pinion. How To Box-In a Differential / Solid Axle Rear-End Housing; . We provide how-to and technical articles, vehicle and build features and examples, plus calculators and lookups that will help you get your ride from dream to driver. The 8.75 (8 3/4) rear end LOADS FROM THE FRONT and IS THE ONLY REAR END THAT DOESN'T HAVE A REAR COVER. Its role in drag racing was limited to primarily Stock, Super Stock, and Factory Experimental Fords. July 30, 2004 11:23PM. with 10 bolt axle. J.T. Plywood pieces work well for shims. Picture is from parts book. Estimated Lead Time: 5-Days. Quality and service was excellent. '73 Ventura, '73 Mustang, '36 Plymouth, '54-56 Ford Pickup 20 0 obj<>stream The 55-57 Chevy car rear-end is almost a bolt in, the perches need to be relocated to the top of the housing though. to change without notice. I have heard that a 1st gen Pontiac Firebird rear is wider, but I am not sure by how much. Vintage 1980 Yamaha Enticer Snowmobile Revival to Former Glory. 0000002004 00000 n If you're running a blower, turbo, nitrous, etc you will probably want to step up to a larger rear like a 9" or 12 bolt. The simple cure when using wide tires with a stock-width rearend was to radius the fenders and let the tires hang out in the breeze. Copyright 1995-2021 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. The new P/O 9.3-inch immediately found its way into hot rods and race cars. '71 Comet '72-73 Torino, STOCK CENTER TO CENTER SPRING PERCH DISTANCE, '69 Chevrolet Beginning with a new line of U.S.-made gearsets in desirable ratios, Fabcraft rekindled the flickering flame of the 9.3-inch. All housings have strong, tapered axle tubes, come in numerous widths, and sport a variety of suspension brackets. 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And even though new internals were available from Fabcraft, the carriers were simply becoming too difficult to find. also note on the A4's (auto's) shifter console if the gear selector for 1 is missing. It'll help you sniff out the right parts and will walk you through building the differential for your gasser project. Mopar Rear Axle. Information provided by:Joe GarciaThe Resto Rod Shop. For many years prior, Olds and Pontiac differentials had been a dominant rear axle in drag racing and other motorsports. Demand exceeded supply, so after several years of planning, designing, and prototyping, Fabcraft Metalworks teamed up with a major U.S. manufacturer to produce a brand new, extreme-duty limited-slip differential for the 9.3-inch called the Trophy Track. Here you can see the three white paint splotches identifying the pinion size and the gears. SiteStats_3379(); Buick/Olds/Pontiac axles are typically retained with bearings. The Pontiac/Oldsmobile 9.3-inch is your axle. 0000015097 00000 n Task Force width ranges at this time. In 1957, the Pontiac and Oldsmobile designs were combined and improved upon, producing a brand new 9.3-inch differential. ; Home 2; Home 3; Home / / pontiac rear end width chart. trailer may be different than pictured. Grand Prix. A: Starting in 1937 Pontiac and Oldsmobile rearend designs slowly began to converge, to the point that in 1957 all major components were virtually interchangeable, with the exception of some brake components, suspension attachments, and axle housing/axle widths. Automotive Technical and Reference Information, Project Cars, Trucks and Salvage Vehicles For Sale. By 1965 GM replaced the 9.3 with a Spicer design using an 8.875-diameter ring gear that mounted the internals in the axle housing rather than a separate carrier. a Custom Classic Truck" Peterson Publication; June or July 1999,