3.00 gears behind a 144- too tall?

6bangerwanab

Well-known member
ok so i finally got an 8 inch for my 61 falcon, but it still only has the stock 144 and 2.77 three speed. it currently has 3.55's in the rear. i was wondering if the 3.00's would be too much, espessially since the 5 lugs i got for it have 195/55's on a 15 inch rim (i think that they will look pretty good, although i would prefer wider) i also have on hand a progressive 2bbl that i have been meaning to install that might take up some slack, but i also have a 3.03 three speed that i can install untill im ready to swap in a t5.
 
I am sure you will be fine.

You probably won't be winning any tractor pulls, but it should get you around town without a problem.
 
My '60 Falcon with a very tired 144 pulled the 3.10 rear acceptably. As long as your tires aren't TOO tall you should be ok. I can't remember how tall 195/55/15s are....I was running 23.5" rubber with the 144.
By the way,a hot 200 will PLAY with the 3.10 gear,lol.

Terry
 
falcon60":1jgcwf4d said:
By the way,a hot 200 will PLAY with the 3.10 gear,lol.

Terry

im thinking of going to 3.10 from my 3.50 because i top out around 60 with the 3.50 and there is nooooo lack of power to get there hahaha

so thanks for the info there :D
 
Bort62":arl2o48t said:
I am sure you will be fine.

You probably won't be winning any tractor pulls, but it should get you around town without a problem.

I would be wary of adding both taller gears AND tires behind a 144. Especially if you are mostly running around town. If it is mostly highway driving then maybe but you will probably get tired of slipping the clutch to takeoff.
Joe
 
fattie64":13pi4ja8 said:
falcon60":13pi4ja8 said:
By the way,a hot 200 will PLAY with the 3.10 gear,lol.

Terry

im thinking of going to 3.10 from my 3.50 because i top out around 60 with the 3.50 and there is nooooo lack of power to get there hahaha

so thanks for the info there :D
I'd say there's a problem with the engine if it tops out at 60 with a 3.50 gear. I ran a 4.11 in my Mustang with 27" tires and it was about 3,000 rpm at 60.
 
I'm running 3:00 with my 14" tires and 170ci. It's not going to win any races, but my main goal was mpg. I get in the low 20s with this set-up. On the freeway, I max at about 95mph.
 
i'd put the 3.03 in until you go t5. the nonsynchro first 2.77 can be a problem with those times when you're going slow, then having to either throttle out in second or stopping to put it in first. :?
 
grocery getter":3vmyma0u said:
i'd put the 3.03 in until you go t5. the nonsynchro first 2.77 can be a problem with those times when you're going slow, then having to either throttle out in second or stopping to put it in first. :?

i double clutch it and it will slide right into first, the 3.03 actually came out of a 73 f100, so how hard would it be to adapt?
 
Not specifically what everyone's talking about but here are some notes I made when I went from my 7-1/4" rear to the 8". The driven gear was changed and they were both pretty close to actual speed compared to my speedometer.

MPH------7.25"(3.5)------8"(2.79)------% decrease in RPM

50---------2900-------------2350-------------19%
55---------3250-------------2500-------------23%
60---------3450-------------2700-------------22%
65---------3750-------------2900-------------23%
70---------3950-------------3100-------------22%
75---------4200-------------3350-------------20%

The 2.79 is a little low for around town but my 200 isn't a real hot rod anyways (yet!). So about a 21.5% decrease in RPM on average at highway speeds.
 
Redfalken":kr1gyt68 said:
Not specifically what everyone's talking about but here are some notes I made when I went from my 7-1/4" rear to the 8". The driven gear was changed and they were both pretty close to actual speed compared to my speedometer.

MPH------7.25"(3.5)------8"(2.79)------% decrease in RPM

50---------2900-------------2350-------------19%
55---------3250-------------2500-------------23%
60---------3450-------------2700-------------22%
65---------3750-------------2900-------------23%
70---------3950-------------3100-------------22%
75---------4200-------------3350-------------20%

The 2.79 is a little low for around town but my 200 isn't a real hot rod anyways (yet!). So about a 21.5% decrease in RPM on average at highway speeds.

what are you currently getting for mileage?
 
I usually get about 13 around town and 18 on the highway. Now, I only work 2 miles from my home so on a cold day I probably spend more time warming up the engine than I do driving!

Also, I haven't done a full tank yet on the highway with the 8" rearend so I'm hoping to break 20 mpg someday.
 
Geezer 300":249p8o9x said:
fattie64":249p8o9x said:
falcon60":249p8o9x said:
By the way,a hot 200 will PLAY with the 3.10 gear,lol.

Terry

im thinking of going to 3.10 from my 3.50 because i top out around 60 with the 3.50 and there is nooooo lack of power to get there hahaha

so thanks for the info there :D
I'd say there's a problem with the engine if it tops out at 60 with a 3.50 gear. I ran a 4.11 in my Mustang with 27" tires and it was about 3,000 rpm at 60.

21" tires and 1:1 final drive gear
 
Geezer 300":26io1fq5 said:
I stand by my statement.

ok then help a brother out here. im 17 so i dont have a whole lot of experience with rearends etc.

it sounds like about 3800-4000 rpm at 55 mph. what could be wrong? its definitely in third gear, and i'm pretty positive that the gear ratio is 3.50:1 (according to owners manual)

thanks in advance

and sorry for thread hijacking
 
fattie64-

Should be about 3500 rpm at 62 mph without converter slippage figured in. Add 200 rpm (about average) for normal converter slip if you have an automatic. You can easily pull a 3.10 rear with your car with those short 21" tires.

Terry
 
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