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Discussion Starter · #1 ·
As I am collecting parts for the 265 build, I am thinking of how to gear the car to best suit the little 265. I have 3:70's in the rear and my Super T-10 is 2:64, 1:73, 1:33, 1:1, first thru 4th. I have been strongly thinking about going with a T-5 that has a first gear more around 3:00 or so. With this i might even bump up to a 4:10 in the rear. I know gearing can really help or hurt the 265 but exactly what to do will be a week long discussion ! I know the old days when there were only a few 4 speeds and ratios to choose from and running 4:10, 4:56, 4:88 or more gears but today there is SO MUCH more to choose from, there should be a better tranny gear/rear end gear combo I can put together. There are (2) more Super T-10"s that have: (1) 2:88, 1:91, 1:33, 1:1 and (2) 3:42, 2:28, 1:46, 1:1. The car will have more street use than track so I am really wondering what all of you think.
 

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If it's mostly street use, then I wouldn't change the rear gears and a T5. The low 1st gear combined with a 4:10 rear gear will make 1st gear like granny gear on a truck 4 speed. Barely get through an intersection and be changing to 2nd. I'd keep the 3.70's if you go to a T5, or even if you went to a 4 speed. If it was a mostly track car, then I'd drop even lower than 4:10, and stay with a 4 or 3 speed to maximize the rpm's of the 265.
I ran a 3 speed behind my '55 with the 283 for a long time, and only changed when I finally blew it. I then went to a 4 speed, but the car was slower with one more shift in the 1/4 mile. Amazing how many 5,000 rpm launches the 3 speed took before it came apart! :)
 

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You really have to settle on what kind of manners your 265 will have. Are you building it to rev high (7000 to 7500 regularly) ? If so do you intend to use the higher rpms on a regular basis? If so then you can use a higher rear gear (4:10 or even up to a 4:88) and let her rpm in each gear. Using that T5 then for the overdrive. One of the neatest cars I remember in my town as a kid was a '69 Boss 429 with 4:88's. When we "scooped the loop" we went down two different back streets to scoop around back to Main Street. I used to stand at the one corner when I knew the "BOSS" was out just to hear him come up that street. Even when he only throttled up a little the rpms came up fast between gears. That sounded the same as some of the lower geared cars when they were going thru the gears at full throttle. But when he did plant his foot, man that thing just screamed, and sounded so good.
So, if you want that kind of fun, and the 265 is built to handle the higher rpms more often, get tall rear gears and an OD. If you are using more normal rpms , like a ceiling of 6000 to 6500, then stay down around 3:90's or even 3:50's if you don't mind the loss in performance. Meaning, if you're just driving it in cruises and to shows etc. and don't care if it runs to it's full potential.
Lots of options but it depends mostly on your expectations of performance and how well the engine is actually built.
I probably didn't help you much, sorry.

Mark L
 

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Discussion Starter · #4 ·
I will be under the 7,000 RPM, more like the 6-6,500 as you said. It will be more of a street car then a drag car but it will get put through the gears from time to time. It will be balanced and blueprinted and will most likely be running a roller cam plus a number of the tricks that the "super stock and stock eliminator" guys use to save HP. Windage in the oil pan and a number of those things are going to help. I will also put my car on a diet ! This is my gearing: Super T-10 2:64, 1:73, 1:33, 1:1, first thru 4th, 3:70's with 30 inch tall tires. With that tall a tire I might get away with a 4.10 gear and no over drive. My only drawback of the T-5 is that it is nowhere as stout as the Super T-10
 

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I think you'll be happy with that combo. Except that 30 inch rear tire may make it a little sluggish. The 4:10 would get that back.
Mark L
 

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Discussion Starter · #6 ·
Currently with the 350 in the car, it is very easy to keep up RPM. I will either go up in gear to a 4.10 or pick a slightly smaller tire.
 

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The T5 wont take much abuse with a 30" tire! I'm guessing very many hard shifts, or hard launches, and you'll be going to a Tremec or a 4 speed. They are only rated for about 250 ft. lbs. torque.
 

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Agreed with Vall. But if I were you I would gear up and keep the tall tires. They look so much better than a shorter tire. With my big Catalina I'm at 31 tall tires and they still look too short. When I buy new I plan to at least a 33 tall. Although a tall tire presents other fitment problems. So you have to do what works for you.

Mark L
 

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Discussion Starter · #9 ·
I agree also about the T-5 and these tires because they bite hard. the 28-30 are the only size that fit and look good. I wasn't able to cut my wheel openings to the tires. My car already had them cut like a front wheel opening and they were very uneven, I had to make them the size they are to work. I will most likely run it as is and hunt up gears later. I wish they made 3.90 gears for my rearend.
 

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I think with your 4-speed and some 4.10 gears (or maybe a little deeper...4.56?),you will be a happy cat.With the 30" tires,I think your cruising rpm with 4.10's would be totally acceptable.
Going from my experience with a snotty little 289 in one of my cars with a 3.70 gear and only 26" tall tire,I can tell you it will be a dog out of the hole acceleration-wise with the hot 265 and the 3.70's.

Scott
 
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