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Over the July 4th weekend I finally upgraded from a 3.00 to 3.55 gear ratio and I love it. With my 90-93 T5, I'm cruising at 70 MPH (approx. 2200-2300 RPM). I'm a weekend cruiser and I've put about 200 miles total on the build (15-25 miles short easy trips at a time)

Since I like to take 100-150 mile weekend road trips, would expressway cruising at around 2700-2800 RPMs put to much on the stock 302?

thanks
jcs
 

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Dimples
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What's your rear tire size? I'm cruising at about the same RPM with my T5 and 3.73's.
 

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1968 Mustang Fastback, 289, T5-5 speed
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Nice. I’m putting a T5 in as we speak so I can run 3.55 gears on the highway.


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1968 Mustang Fastback, 289, T5-5 speed
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Off topic but did you put an aftermarket shifter on the T5?


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Over the July 4th weekend I finally upgraded from a 3.00 to 3.55 gear ratio and I love it. With my 90-93 T5, I'm cruising at 70 MPH (approx. 2200-2300 RPM). I'm a weekend cruiser and I've put about 200 miles total on the build (15-25 miles short easy trips at a time)

Since I like to take 100-150 mile weekend road trips, would expressway cruising at around 2700-2800 RPMs put to much on the stock 302?

thanks
jcs
remember that these engines were designed before overdrive transmissions, and often times had rear gears up to 3.89-4.11 available from the factory, and at the time the speed limits were around 75mph, so your 302 wont be bothered by the higher cruise rpms. the constabulary might be bothered depending on how far over teh speed limit you will be.
 

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Dimples
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Off topic but did you put an aftermarket shifter on the T5?
You have to. I mean, you don’t HAVE to, but everyone should. The difference is night and day, they’re not that expensive and these days, it kind of doesn’t matter which one you get as long as it has positive stops because they’re all good.
 

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Over the July 4th weekend I finally upgraded from a 3.00 to 3.55 gear ratio and I love it. With my 90-93 T5, I'm cruising at 70 MPH (approx. 2200-2300 RPM). I'm a weekend cruiser and I've put about 200 miles total on the build (15-25 miles short easy trips at a time)

Since I like to take 100-150 mile weekend road trips, would expressway cruising at around 2700-2800 RPMs put to much on the stock 302?

thanks
jcs
Great! Now tell me the difference in the acceleration from a stop! I’m debating 3.55 gears also.

Allen
 

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Since I like to take 100-150 mile weekend road trips, would expressway cruising at around 2700-2800 RPMs put to much on the stock 302?
thanks
jcs
For your info, and others who haven't heard, back in the mid 60's Ford rented Daytona for 40 something days. They ran several cars with 289s all those 40 days only to stop for service. Only a few minor repairs were needed. Btw, they averaged over 100 mph.

I'll think you'll be fine.
 

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1966 GT Fastback, 289, TKO 5-spd, EFI, 4-discs, TCP coilovers
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Over the July 4th weekend I finally upgraded from a 3.00 to 3.55 gear ratio and I love it. With my 90-93 T5, I'm cruising at 70 MPH (approx. 2200-2300 RPM). I'm a weekend cruiser and I've put about 200 miles total on the build (15-25 miles short easy trips at a time)

Since I like to take 100-150 mile weekend road trips, would expressway cruising at around 2700-2800 RPMs put to much on the stock 302?

thanks
jcs
I'm with you in this one. I just made that same gearing change, and it is fantastic - great acceleration, nice shift points plus ability to use 4th gear around town. But I'm confused - if you're able to cruise the expressway at 70 MPH @ 22-2300 RPM (mine is the same), then why are you concerned about 2700-2800 RPM for your 302? That would have you going 100 MPH - most municipalities frown on that!
 

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1966 GT Fastback, 289, TKO 5-spd, EFI, 4-discs, TCP coilovers
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Great! Now tell me the difference in the acceleration from a stop! I’m debating 3.55 gears also.

Allen
It's like a whole different car, especially if you have the Tremec trans with the 3.27 1st gear.
 

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1968 Mustang Fastback, 289, T5-5 speed
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It's like a whole different car, especially if you have the Tremec trans with the 3.27 1st gear.
Nice. I just put a T5 in. Next is 3.55 LS from my 2.79 open. Can’t wait!


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I've had 3.55s and 3.73s with my T-5 and I really like the 3.55s for accleration but highway cruising, as well. Great combo.
 

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1966 GT Fastback, 289, TKO 5-spd, EFI, 4-discs, TCP coilovers
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I've had 3.55s and 3.73s with my T-5 and I really like the 3.55s for accleration but highway cruising, as well. Great combo.
Best compromise for both kinds of driving, for sure ...
 

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For those that went with the 3.55 - did you keep the rear end or jump up to 9"?
 

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1966 GT Fastback, 289, TKO 5-spd, EFI, 4-discs, TCP coilovers
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For those that went with the 3.55 - did you keep the rear end or jump up to 9"?
I'm only making about 315 HP, so the beef of a 9" isn't necessary. I just did a full rehab on my 8", and I could stay with the rear disc conversion that fits to the 8" small bearing mount.
 
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