ring and pinion help

Little 200

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I have an early production 67 mustang with 200 in it . It is stock as far as i know except i have a weber 32/36 2 bbl carb and headers on it . As it was restored i put 8 inch rear end that has 2.79 ratio . On hwy it does ok but has no low end get up . Any suggestions for some low end get up ? What RPM does the 200 like for cruising down road ? Usually run around 60 -65 on road . Thanks for any help!!
 

wsa111

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I also have a 67 with a C4 & 8" rear. I have 3.25 in mine & it gives you a little more power on acceration & 3K cruising is in the 65 mph area.
I also see you installed a weber carb. That helped the power output.
What distributor are you using??? If you ever need help in that area see my listings in the small six for sale section of the forum. Bill
 

BigBlue94

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Judging by a 25.5" diameter tire and no overdrive, you should be around 2400 rpm at 65mph. Swapping to 3.25 gears would put you about 2800 rpms. Swapping to an aggressive 3.5 rear end ratio would put you right about 3000 rpms.

My 300 chuggs along at 3000 rpms at 70mph just fine.

My only experience with a 200-6 is in an old 74 bronco with 31" tires, 3OTT trans, and 4.10 gears. At 65mph it was about 2900 rpms and did just fine. Plenty of power at that rpm range.

When running these kinds of rpms, it is very important to have the oiling system in tip top shape and to use good oil. And change it every 3000 miles.
 

bubba22349

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X3, a 2.79 rear gear is for sure not a good choice for a manual transmission if that's what you have those cars usally were equipped with at least a 3.25 or mostly the 3.50's but many other ratios were available and could of been special ordered. Depending on how your car is driven most of the time like for mostly city type driving of a max of 45 to 50 MPH than a 3.50 gear would make sense or maybe even a 3.89 if you wanted some more spirited driving. If you do lots or mostly Hy Way / Freeway driving of 65 to 70 MPH than a 3.50 still works but a 3.25 would lower the steady state cruise engine RPM some if your looking for good MPG. It's all a balancing act of what you want your car to be able to do. Also if you still have the door or door jamb Warrentee Tag I can decode that info so you can know what rear axle gear ratio your car had when it was new that might also help you decide. Best of luck
 

Little 200

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We use this for car shows and short trips but not as a daily driver on interstate so around 60 is about where it runs at . I looked at a rear end calculator from Strange Engineering at a 3.40 and it shows 2900 rpm at 60 mph . Is that too high to run ? Thanks to all you guys that replied .Wsa 111 i am not sure as to the maker of the distributor just that it is electronic . Now i am going to go look !
 

BigBlue94

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We use this for car shows and short trips but not as a daily driver on interstate so around 60 is about where it runs at . I looked at a rear end calculator from Strange Engineering at a 3.40 and it shows 2900 rpm at 60 mph . Is that too high to run ? Thanks to all you guys that replied .Wsa 111 i am not sure as to the maker of the distributor just that it is electronic . Now i am going to go look !
Nope. 2900 is fine, especially in a non-DD. As i said, just keep the oil and related system in great shape. I drove my 300 700 miles in one day at 3000 rpms, twice. No issues.
 

bmbm40

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I am a big fan of that 1967 body style and my other favorite is the 65-66 and would take any of those I could get! Maybe not too far in the future.
That Weber is a progressive carb right? so seems like you would kind of need to step on the gas quite a bit to move off the line especially with a higher axle ratio. You might benefit from a custom curved distributor and a total performance ignition set up like a hot coil, big wires etc to get a little more low end grunt for jack rabbit starts. Also long tube headers reportedly increase low end torque. To go even further you could get a cam made for low end torque. wsa111 is definitely the best source of info on the ignition and much more.
C4 has a reputation as one of the best trans on the planet but a 4 speed od is what is needed for all around driving which can be had as an AOD but not sure of compatibility with your block. And since you are not on the highway much may not be a good choice anyway.
 
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