Yep, around here the parts peddlers on craigslist and at the local swap meets think anything that is a nine inch is gold no matter what the gear ratio or what it came out of is.
If it were me I'd want to save my pennnies for a 700R4 or 2004R o/d trans with 3.55s and run a 28.5" - 29" rear tire. In a perfect world 3.70-3.89 would be just the ticket, but thats just me....
We have a 29 Coupe with a 350/350 drive train. We are running a 3.92 Dana 44 in it and the rear tires are 7.50x16. It will run down the freeway with traffic fine at 3,000 to 3,200 rpm, any faster than that and it feels to fast personally. I think 3,000 is about 70 or 75. So it will go faster than I need it to with that gearing. I have a friend that just put 3.56 gears in the 9" in his Nash and he seems very happy with it, but knowing him I doubt it will see much freeway time....
Anyone else notice that the OP came on, asked a question, a bunch of people asked for more info and gave some answers, but the OP hasn't been back in two days?
Yeah, it's a guess on my part that traffic is going 70, I don't have a speedo and traffic here is always running at about 70 or a bit over according to my HHR. That seems plenty fast in a Model A with a 40 Ford front end and bias ply tires to me....
Is there a 3.55 gear available for the 9in? Think you probably mean 3.50...not that it matters. I'm betting it'll work very well, but it'd help to know what the tire OD and the cam specs (any idea on RPM @ torque peak?) are...price is fine, if the housing fits what you're trying to do run it and if you need to change the gear later 3.00 gearsets for that axle pretty much grow on trees, might be able to find you a 2.75 set here I'd send you for the shipping cost. I think a 9in Ford is also a fair amount of unsprung weight for an A transverse buggy-spring suspension, are you doing something different?
Low price if anything. I've been running into some folks who have been really proud of their old 9" junk yard rearends (more proud than $250).
Depends on a lot of things, tire diameter, usuable RPM range of the engine, weight of vehicle, intended use of the vehicle. My engine is just starting to run @ 3k for instance so I run in the 3,000 to 3,200 range all the time a gear in the 3.5 range is good for me. Maybe with a stock 350 in a light car not so good.
My '33 Willys street / strip car has a 300 ci six / C6 and 3.50 nine inch with 30" tall tires. It gets 17 mpg and turns 13 second quarters. I think the 3.50 is a great compromise between performance and highway cruisin'. On an unrelated but interesting note my dragstrip-only RPU has 2.47 rear gears and turns 11 second quarters with an equally healthy inline six. Go figger.
I ran 3.55 with a 350sbc/ turbo400, 9" in my 31' and loved it. I want to say with 30.5" tires I was running 2500 rpms at 70 but can't remember for sure!
It probably has half the weight, so it gets a lot more mph with the same hp. So it needs less gear, to keep rpm thru the lights at the engine's red line.
I run 3.55's in my 9 inch in my 57 chevy. 454 bb . I have a 700r and 29.5 inch tires , this set up is perfect with the overdrive , turn about 2400 at 65 mph . I bought mine for 25 bucks. It had trees growing through it ! after narrowing it , strange axles , bearings , posi , center section , disk brakes , installing it , and backlash , I got bout 1000 bucks in it , and did all the work myself , 250 bucks aint bad at all.
wow, things have changed. I thought I was turning pussy dropping to 4.10s from 4.56 to keep wheel spin down. Of course I run either 29.5 or 30.25" tires though. Only about 30k miles running from CT to NY, NH, MA, NJ PA etc... Maybe I need an OD trans? Oh, never mind-I thought this was a hot rod site.
I've got 3.36's in mine with a 350/350 and 205/75/14's Sucks ass on the highway. I'm spinning about 3k at 60 mph. First time I find a good rear end with 2.76 or higher ratio Im doing the swap.
205/75-14s are pretty short tires. 2.75s are fine if you have a car that weighs nothing. Otherwise, that's why four, five, six, seven, eight-speed transmissions were developed
I drive a ponycar with a mild 302, C4, and 3.55's. It's a real good setup. Jumps at the lights, short freeways runs are ok. But I wouldn't want to take it to LA every day. I once had a 4.11, and honestly the car feels faster with 3.55's.
Rear end gear ratio is a very subjective thing, and depends on where you drive the most and what you want out of the car. Also, if you have an OD trans that changes the whole game. What I consider a good ratio and what you consider a good ratio might be two different things. 3.50 ish gears are not deep at all, even with a non OD trans. In fact, they are just about ideal giving good performance around town and decent rpms on the interstate. BUT, if you are running short tires that also changes things. The final factor is gas milage. We never cared about it when gas was 25 cents a gallon, but today we do. If good gas milage is important to you then something in the 2.79-3.00 range might be better, but the car will not be as responsive around town. I'm currently running 4.30 gears with a 29.5 inch rear tire and absolutely love it around town, but I have to admit that running at 3500 rpms on the highway at 70 mph isn't ideal, although I have done it for 5 hours at a time. Most of my driving is around town so I chose the deeper gears. Don
Don I think a big part of it has to do with how your engine is tunned as well. You really want to keep your engine in its power band for many reasons, one of them being is that is where is is burning fuel most efficiently. If you are right at the bottom of your power band @ say 3500 RPM you really don't want to be lugging it around @ 1800 RPM. If fuel mileage is a concern your mileage will go right out the window at the lower RPM not to mention what it is doing to your engine. Useing the 3500 RPM example, if you were rto run 2.79 gears you would way exceed the speed limit in about any state in the union if you were trying to keep your car in its power band.
Put a 4:11 rear in it with an overdrive trans with a .73 OD. You will have a vicious hole shot yet good highway legs. You will save some money, if you can keep your foot out of it!
Ha, why go racing around? I want everybody to get a good long look when I drive by. Remember, customs are for GETTING the pussy.
Important enough to get coverage on the '11 HAMB Calander. It is a belly button, remember anything without a belly button has no soul.
I started with a 350 and TH350 in my Model A with 3.00:1 gears, 9" ford rear. 3.55 is not a good thing for the freeway. I am currently running a 700R4, which has a lower first gear and overdrive and it is great on the freeway. 3.55:1 may be a bit more snappy off the line for me, and I am considering a change. (already have the pumpkin)
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