|
rear-end gears |
Post Reply 
|
| Author | |
fordpower 
Senior Member 
Joined: 02-September-2010 Location: willseyville,ny Status: Offline Points: 1807 |
 Post Options
 Thanks(0)
 Quote Reply
 Topic: rear-end gearsPosted: 14-May-2024 at 12:42AM |
|
Ok looking for new set up for 8in I want 3.55 or 3.75 online people are posting 4.56 and higher ring and pinion. One person said 4.56 is a 3.50 rear end I am confused.
|
|
 |
|
|
derth
New Member 
Joined: 06-October-2022 Location: VA Status: Offline Points: 35 |
Post Options
Thanks(0)
Quote Reply
Posted: 14-May-2024 at 4:04AM |
|
Without knowing anything about the 8 inch, I will mention that final gear ratio is a matter of tire size, transmission gearing and rear gearing. Depending on goals, you could start by finding your desired rpm at cruise speed and then working from there. Depending on transmission, a 4.56 may give you a 3.5 final gearing? Sorry if this is not helpful, but it was confusing for me first time I dealt with it.
Well, of course, now that I'm thinking about it, all the transmissions that came in these cars are 1:1 in 3rd, so everything I just said is useless unless you've got something with overdrive. Edited by derth - 14-May-2024 at 4:12AM |
|
|
|
|
fordpower
Senior Member
Joined: 02-September-2010 Location: willseyville,ny Status: Offline Points: 1807 |
Post Options
Thanks(0)
Quote Reply
Posted: 14-May-2024 at 5:39AM |
|
thanks
|
|
|
|
|
72FordGTS
Admin Group 
GTS.org Admin Joined: 06-September-2005 Location: Ontario, Canada Status: Offline Points: 6780 |
Post Options
Thanks(0)
Quote Reply
Posted: 15-May-2024 at 6:02AM |
|
Are you sure your car has an 8" rear, and not a 9"? What gears are you running now? A lot of those late 70s cars had really steep gears, like 2.50:1. What size rear tires do you have? What type of driving do you do with your car? Is your engine stock or modified? What are you hoping to achieve with new gears? Ford 8" rear have slightly different rations than Ford 9" rears. You could upgrade to 3:00:1, 3,40:1, 3.55:1 or 3.80:1. I probably wouldn't go much lower gears than that for a street driver. |
|
|
Vince
1972 Ford GTS Sportsroof - Survivor, One Family car GTS.org Admin |
|
|
|
|
fordpower
Senior Member
Joined: 02-September-2010 Location: willseyville,ny Status: Offline Points: 1807 |
Post Options
Thanks(0)
Quote Reply
Posted: 15-May-2024 at 12:39PM |
|
It is for my pinto going with AOD it has 2.75 there about.Someone had a 4.56 ring and pinion locker clams that is a 3.55. Just a thought I have a 3.25 non locker but people want 4-500 to put new bearings and set it up I have the bearings.
|
|
|
|
|
72 RS 351
Senior Member
Joined: 04-September-2014 Location: Knoxville TN Status: Online Points: 3445 |
Post Options
Thanks(0)
Quote Reply
Posted: 16-May-2024 at 2:49PM |
|
The 3.25:1 range is not a bad ratio for an AOD car, the OD is .70:1, typical for all over drive trannies. A 3.5 or 3.75ish is also very good depending on the vehicle weight and power level.
|
|
|
Don
73 Ranchero "Sport 72 front end", floor shift/console, planning EFI 7000 rpm 351 stroker 73 Ranchero GT 351C-4V &4R70W for sale later. 92 Lincoln Mark VII SE GTC, OBDII 347/4R70W |
|
|
|
|
72FordGTS
Admin Group
GTS.org Admin Joined: 06-September-2005 Location: Ontario, Canada Status: Offline Points: 6780 |
Post Options
Thanks(0)
Quote Reply
Posted: 17-May-2024 at 8:42AM |
|
With a little Pinto, assuming it's still a 4 cylinder, be careful not to over gear it. With the .67 OD, a 3.25 gear will give you a 2.18:1 overall ratio. A 3.80 gear seat gives you a 2.54 overall ratio with an AOD.
|
|
|
Vince
1972 Ford GTS Sportsroof - Survivor, One Family car GTS.org Admin |
|
|
|
|
72 RS 351
Senior Member
Joined: 04-September-2014 Location: Knoxville TN Status: Online Points: 3445 |
Post Options
Thanks(0)
Quote Reply
Posted: 17-May-2024 at 11:21AM |
|
Well given an AOD, it'd likely be a V8 I hope, but a V6 at the least. I know how tight the engine bay is, my best friend's nephew had a Cleveland in one in the mid 80's. I hate to think how tight it is for headers, the trans, plus the exhaust. Good luck of course.
|
|
|
Don
73 Ranchero "Sport 72 front end", floor shift/console, planning EFI 7000 rpm 351 stroker 73 Ranchero GT 351C-4V &4R70W for sale later. 92 Lincoln Mark VII SE GTC, OBDII 347/4R70W |
|
|
|
|
fordpower
Senior Member
Joined: 02-September-2010 Location: willseyville,ny Status: Offline Points: 1807 |
Post Options
Thanks(0)
Quote Reply
Posted: 18-May-2024 at 2:12AM |
|
It's a 302 bought it yrs ago for 1000 because who knows wife would not ride in it to loud and 6in hood scoop . took it apart found right oil pan and got old. my question was people saying 4.56 ring and pinion is a 355 ratio.
|
|
|
|
|
Rockatansky
Senior Member
Joined: 30-July-2010 Location: On The Road Status: Offline Points: 6398 |
Post Options
Thanks(0)
Quote Reply
Posted: 18-May-2024 at 6:36AM |
|
what they're saying, based on their own specific combo factoring in tire size i imagine? is that with OD they can run a 4.56 gear and it equates to the 3.55 gear w/o OD
|
|
|
72 GT Ute
|
|
|
|
|
fordpower
Senior Member
Joined: 02-September-2010 Location: willseyville,ny Status: Offline Points: 1807 |
Post Options
Thanks(0)
Quote Reply
Posted: 18-May-2024 at 12:26PM |
|
thanks.
|
|
|
|
|
Post Reply
|
|
| Tweet |
| Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |
Topic Options