SpeedTalk Store - Opinion Columns

Highest gear ratio for Ford 9 inch ?

Transmission to Rear-end

Moderator: Team

Highest gear ratio for Ford 9 inch ?

Postby mtkawboy » Thu Dec 30, 2010 4:42 pm

Could anyone tell me what the highest after market or factory gear available for a Ford 9 inch rear is ? I know if a 2.47 out of a Lincoln Versailles and a 2.33 out of a golf cart but dont know where you'ld get one. What kind of golf cart needs a 9 inch anyway ? This is for a Bonneville lakester build. Narrowed 9 inch is already in it so changing rears isnt an option. Sorry I posted this before in the wrong place
mtkawboy
Pro
Pro
 
Posts: 262
Joined: Sat Jul 17, 2004 12:04 pm
Location: Billings Mt

Re: Highest gear ratio for Ford 9 inch ?

Postby quicksilver » Sat Mar 05, 2011 1:47 am

2.47 is the lowest I have seen or heard of-

but after some extensive googling- a 2.33 is out there, and came in a select few Lincoln's in the late 60's and early 70's. That was it. Some were adapted to other things (like golf carts and the like) but thats it. They are apparently tough to find nowadays and few and far between.
quicksilver
Member
Member
 
Posts: 167
Joined: Tue Apr 27, 2010 8:02 pm

Re: Highest gear ratio for Ford 9 inch ?

Postby mike22l » Wed Mar 09, 2011 9:58 pm

I build complete drivetrains for three race teams for 5 years now. The highest ratio you can put in a 9 in Ford is 7.00 to 1 in a stock housing. I know what I`m doing so I do get away with running a 7.16. Anything higher than this like a 7.33 you must run an aftermarket for example, a Strange housing or you end up with a rear end full of scrap iron. Mike
mike22l
Pro
Pro
 
Posts: 209
Joined: Wed Mar 09, 2011 1:26 pm

Re: Highest gear ratio for Ford 9 inch ?

Postby ZIGGY » Thu Mar 10, 2011 9:44 am

Read the original post. 7:00 is a low gear.
ZIGGY
Guru
Guru
 
Posts: 1139
Joined: Mon Mar 05, 2007 3:15 am
Location: Dallas, Texas

Re: Highest gear ratio for Ford 9 inch ?

Postby fastman614 » Fri Mar 11, 2011 3:18 pm

The 2.33 to 1 gearsets do exist..... they ARe hard to find and there is nobody that I have spoken to yet who seems to know exactly what cars they were in. The popular belief is a 4 door sedan from the late 60s to the early 70s....they are believed to be more in abundance in the areas east of the Rocky Mountains, with sets having been found in Texas in recent years.....Also, they were 9 3/8" gearsets-NOT 9".... the 3rd member fits a 9" housing and 31 spline axles ONLY do fit the differential but the housing needs a bit of grinding in order to allow the bigger ring gear to pass through the opening. Incidentally,9 3/8" gearsets and 3rd members were used in SOME Ford pickup trucks. There IS a visible difference in the ribbing on the 9 3/8" 3rd member housing. Several intenet sites show pictorial examples of it. Do look it up if you are serious about finding it. BTW, what are you trying to do with these gears- go fast at Bonneville or get better fuel economy? Happy hunting!

There is one other option for getting lower gear ratios into a Ford .... Strange Engineering makes a center section for a Ford 9" housing that takes Chev 12 bolt gears.... I do not know all of the answers for this but it is my understanding that the GM 8.5 inch ten bolt gears and carriers can be adapted to this housing. You can then get gears down to 2.41 to 1 and, if my source of information is correct, Cadilliac 2.29 to 1 gears will also be adaptable.... Understand that I am NOT stating this as fact!... It is merely what I am led to believe... some early checking of dimensions seems to indicate that this a real possibility though.
fastman614
New Member
New Member
 
Posts: 1
Joined: Fri Mar 11, 2011 3:01 pm

Re: Highest gear ratio for Ford 9 inch ?

Postby In-Tech » Sat Mar 12, 2011 12:25 pm

I can't remember if they are 2.56:1 or 2:62:1, but I've got a used set you are welcome to.
-Carl
In-Tech
Expert
Expert
 
Posts: 788
Joined: Wed Apr 21, 2010 3:35 am

Re: Highest gear ratio for Ford 9 inch ?

Postby mtkawboy » Wed Mar 16, 2011 1:06 pm

Bonneville lakester build, vintage engine
mtkawboy
Pro
Pro
 
Posts: 262
Joined: Sat Jul 17, 2004 12:04 pm
Location: Billings Mt

Re: Highest gear ratio for Ford 9 inch ?

Postby jeff swisher » Thu Mar 17, 2011 9:42 pm

the answer i have is 2.29 to 1..from a mid to late 70's ford car with a 351m and a c6..i think
it was a cougar xr7 1977 year ...absolute blast to drive a car that has some power with 229's...
95 mph in first in my old nova at 6500rpm...that is like a 577 final if you leave the th350 in 1st gear
and 348 final in 2nd
i thought this question was asked before and i answered it,,,but i could not find it...and i could not find the
other car on craigslist that was simillar..so i could have another set :(
jeff swisher
Expert
Expert
 
Posts: 788
Joined: Wed May 23, 2007 10:13 am
Location: yukon ok.

Re: Highest gear ratio for Ford 9 inch ?

Postby Warpspeed » Sun Jul 03, 2011 3:50 am

It all sounds rather difficult....

How about an overdrive transmission ?
Cheers, Tony.
Warpspeed
Guru
Guru
 
Posts: 1246
Joined: Fri Nov 17, 2006 4:10 pm

Re: Highest gear ratio for Ford 9 inch ?

Postby DrillDawg » Sun Jul 03, 2011 4:28 am

You can also find the 9-3/8" in 60's Lincoln's.

DD
“Unthinking respect for authority is the greatest enemy of truth.”
Science is the shifting water eroding at the steadfast rock of religion.
One benefit of religion is that you will never know that your wrong. It's the perfect fantasy.
DrillDawg
Guru
Guru
 
Posts: 1159
Joined: Tue Jul 06, 2010 10:03 am


Return to Driveline

Who is online

Users browsing this forum: No registered users and 2 guests