Ok so i have rear end questions, and if this has been brought up already in a thread that i cant find i apologize and please direct me to the tread. I have a 55 fairlane that i just put a 390 with a c6 in and i am looking to change the gears out so its more of a highway crusier. what i have found is the lowest numerical gear they have for the rear in the car is a 330 gear ratio but i would like to get down to the 300 gear ratio witch would mean changing out the rear for like a 8.8, or a 9in. so do any of you guys have an idea of what will fit the best or what route i should go? thanks for your help guys, i always get great info here.
When I had my 63 F-100, I was thinking about swapping the rear end for something with more teeth (was gonna put in a hopped up 408 Stroker). I googled 1963 Ford F-100 Rearend Width, and I happened to find a chart that had a bunch od Chevy, Mopar, and Ford rear end widths. It helped me to pick out one that would work and was close to or the same size as the one I would be removing. I will look around here for it, and if I find it, I will give you the website I got it from. Dunno if you've tried this yet, but its worth a shot if you haven't.
i have a ranger rear in mine. its not a direct bolt. you have to move or install the spring perchs in a diefrent location. a explorer rear has bigger brakes on the drums and 96 - 01 have disk. still will have to relocate the perchs. 57, 8, 9 ford car 9 inch are sposed to be direct bolt.
ya that is what i have heard about the fords also. I have also been told that the rear in the car is a 8in ford and if that is the case i can just change the gears out, but i cant seam to find any info to comfirm that.
If you can find the heavy duty five stud 8 inch, there were really a lot of them with 2.88 gears. Mt 55 sedan has a 1990 Ranger rear, 8.8 3.73 traction lok. It is 56 7/8 outside to outside. You may get gears for those down to 3.0 You will have to cut the spring mounts off and put new ones on the bottom.
I changed my rearend in my 53 customline with a 1967 Ford Mustang 8.8 with 280 gears. The measurement from backing plate to backing plate are the same and the breaks bolted right up no h***le. The leaf spring perches was the only thing that required adjustment.
An 8" rear from a Mustang usually came with a 2.79 but many also came with a 3.00 . You car get some other gears up to 4.10 but if you look around you can find a 3.00 gear set already in a 3rd member so all you need to do is a swap ! Jim
[FONT=Arial,Helvetica][SIZE=-1]A 3.00 at 60 mph with a 27" tre is about 2300 rpms . They don't show a 3.08 so you will end up wuth a slight lower rpm . Either way you will be good to go .[/SIZE][/FONT] Jim
I ran it on a calculated online chart,with 3.08's@ 2500 RPM= 65.2 MPH 3,000RPM = 78.24 MPH with the modifications you have that should work well but If you had an AOD with 4.10's in overdrive 3,000RPM=90.42 MPH 2,500RPM= 75.35MPH big difference! Off the line the AOD w/4.10's would smoke the C4 with 3.08's.
If you know the rear end ratio of the car the engine/trans came from you'll know the most efficient ratio to run in your '55 - ***uming the engine is stock and the tire size is roughly the same. If the engine has a different cam or if the torque converter has been changed, however, all bets are off. These two items greatly alter the efficiency of the engine at any given rpm and will usually dictate that you use a higher (numerical) rear end ratio than was most efficient when the engine/transmission was stock. With a stock 390/C6 and a 215/75 R 15 rear tire I'd be looking at a 2.8 to 3.10 rear gear for good highway efficiency. You don't have to worry about performance loss with these "highway" gears because that engine will smoke street tires at will to a point well beyond the legal speed limit. I am a big fan of the old school '57 - '59 Ford 9-inch because gears are widely available and you simply can't hurt 'em no matter how you try.
Well I ended up putting a ford ranger rear in new posi new guts and 308 gears...........This worked out perfect car runs on the freeway like a DREAM!! I can stay way ahead of traffic with ease. Around town its not as fun but still good enough to get you in trouble but for the freeway fun I wouldnt change a thing. 302/c4
well im thinking of probably doing the 8.8 rear. i was trying to just change the center section due to money constraints and not wanting to do the drive shaft so soon after i had one build but its really hard to find the ratio i would like. I found a guy that would sell me a complete 8.8 with 300 gears for like 250 bucks so i dont think i can p*** at that for sure. that is going to be the last thing the car needs. just put the areostar springs in last weekend with new shocks and the car rides like a dream and sits really nice. so if i can get it to cruise down the hiway better it would basically be game on. the car is just such a joy to drive.
Buy an early Mustang 8" rear . Most came with the 2.79 gears and some had the 3.00 gears . They are an easy swap and will hold up just fine to a Fe 390 ! I drag raced with the 8" rear and never broke one yet ! Can find them for $200 or less ! Jim
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