70 vert t5 tranny

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Ruffrider
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70 vert t5 tranny

#1

Post by Ruffrider »

Hay folks have a 351c 4 barrel t5 tranny. Engine rpms are high to me will verify in am just installed a tac. In my wandering around the forum I have seen guys installing 3.50 gear sets an being happy with that. I am wanting to cruse at 80 mph in the 1800 rpm range. I would like to see miles @ what rpm as a reference.
Thanks. Ralph
67 XR 7 Gray 289 auto
70 Orange / Black Vert 351 5 speed
74 International Scout II total renovation (sold) :D
78 Scout II torn down to frame getin there
97 2500 4x4 Suburban
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catlover
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Re: 70 vert t5 tranny

#2

Post by catlover »

I think you are right on the money.
I am running 3.80 rear gear with O/D and at 70 MPH (they don't like us to run 80 around here) I am tacking 2100.
There is never time to do it right, but always time to do it over

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69 Elim. 428 SCJ orange/ white
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bmwhd1
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Re: 70 vert t5 tranny

#3

Post by bmwhd1 »

T5s can have different rations for 5th so without knowing which one you have it is hard to say for certain. In my '70 with a 0.63 5th and 3.50 pumpkin I'm seeing more like 2,100 rpm at 80.
Todd

'70 Conv, 351C-4V, T5z
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CougarCJ
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Re: 70 vert t5 tranny

#4

Post by CougarCJ »

There are online calculators for this. Need to also factor in the rear tire size.

For 1800 rpms at 80 mph, you would probably want to look into a 6 speed with double overdrive.
Scott Behncke 1968 XR7, 302-4V (Autolite 4100D conversion), 5 Speed, 3L50 TL,
Carcheologist - West Coast Classic Cougar

Ruffrider
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Re: 70 vert t5 tranny

#5

Post by Ruffrider »

Well at 80mph turning 3300 rpm at 70 turning 2100 rpm. 3300 is way to high just for crusing. Running 14 in rims with 215 70 r15 tires.
Sure would appreciate one of you numbers fellas figure out what I got an what I want. 2000 rpm at 80!!! Any slower an a blonde in an suv will run all over ya.
67 XR 7 Gray 289 auto
70 Orange / Black Vert 351 5 speed
74 International Scout II total renovation (sold) :D
78 Scout II torn down to frame getin there
97 2500 4x4 Suburban
2015 Ford 4x4 350 dually Desel
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xr7g428
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Re: 70 vert t5 tranny

#6

Post by xr7g428 »

With a .67 overdrive, typical for Ford AOD, you will need a 2.80 rear axle with 215/70 14 tires (25.85 inches tall). That will put you at 1952 RPM at 80 mph.

I had this exact setup in a '68 with a Ford 302 crate motor and I hated it. A 3.50 rear gear will put you at about 2500 RPM and be much more fun to drive.
Bill Basore,

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'67 XR7 GT 390 4 speed, AC, AM FM, Lime Frost Green
'68 XR7-G 428CJ C6, Tilt-Away, AM, Black Cherry
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Re: 70 vert t5 tranny

#7

Post by xr7g428 »

The numbers you posted don't make any sense. With a 3.0 you would be at 3189 RPM at 80, and 2790 at 70.
80mph turning 3300 rpm at 70 turning 2100 rpm
Bill Basore,

Fuel Sender Rebuilding, Gauge Testers, and Reproduction Cougar Parts:
Desert Classic Parts
The only magazine ever dedicated to the Classic Mercury Cougar
Legendary Cougar Magazine
Currently in the Cat House
'67 XR7 GT 390 4 speed, AC, AM FM, Lime Frost Green
'68 XR7-G 428CJ C6, Tilt-Away, AM, Black Cherry
'68 XR7-G 390 4 speed, Sunroof, Cardinal Red
'68 XR7 GT-E 427 C6 AM Cardinal Red
'68 XR7 resto mod 351W, soon to be AOD, Black Cherry
Ruffrider
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Re: 70 vert t5 tranny

#8

Post by Ruffrider »

Well the tac may not be the most accurate. But that's the numbers I was getting. That 3.50 gear set may do the trick. Thanks for your replys.
Be Safe. Ralph
67 XR 7 Gray 289 auto
70 Orange / Black Vert 351 5 speed
74 International Scout II total renovation (sold) :D
78 Scout II torn down to frame getin there
97 2500 4x4 Suburban
2015 Ford 4x4 350 dually Desel
Ruffrider
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Re: 70 vert t5 tranny

#9

Post by Ruffrider »

Hay gentleman. Ok rear tire 1 full rotation have 3 3/4 turns of drive shaft. What's my gear ratio?? Need some help!!
Thanks. Ralph
67 XR 7 Gray 289 auto
70 Orange / Black Vert 351 5 speed
74 International Scout II total renovation (sold) :D
78 Scout II torn down to frame getin there
97 2500 4x4 Suburban
2015 Ford 4x4 350 dually Desel
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PacificaXR7GT
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Re: 70 vert t5 tranny

#10

Post by PacificaXR7GT »

3.75. Right?
Steve
CCOA #9998
1968 XR7 GT 4 speed - Augusta Green / Dark Ivy Gold
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