I just took apart the ford 9" rear that came with my 1930 Model A project. It was pulled from a 1960 ford not sure of the model. It has no vent, just one bolt holding the brass brake line splitter. The bolt hole is too small for a typical vent tube so i would just tap a larger hole for the vent. Should i install a vent tube? This car has been sitting since 1975 so i need to check every thing on the car. So the rear gear ratio is 4.57 which i think is to high. The car will be a boulevard cruiser, local car shows no long trips. The engine is a ford 289 HI PO with a 4 speed close ratio ford top loader. What is a good ratio for this set up? The tires will be about 28" tall Thanks for your help.
I think you mean too low of a ratio. If your rear tires are around 30" tall, a gear in the 3.25 to 3.50 ratio is in the ballpark. Love those 289's !
I had a 49 Ford pickup with a stock 289/auto and it had a 4.27 ratio rear gear. Loved it! I suppose your model A prolly weighs a little less than 3000#. The 4.57s would be a blast around town but it'd be singing to you at anything over 55 mph. With the short stroke 289 I wouldn't want to go any higher gear than a 3.73. In fact, I'd drive it with the 4.57s with a 30-31 inch tire and just see if you like it before I did any changes. If you really just drive it in town and very short runs, the 4.57s might just make you happy. The car would be a slug with 3.00s or higher. I drove my 64 'vette with 4.10s in it as a daily driver and drove it on trips...loved it!
Leave the rear end as is, but swap the trans for a mustang v8 T5 [0.68 overdrive] it will cruise 65mph at 2420 rpm with 28" tyres and 4.56 rear end, Plus it will really wake up in the lower 4 gears. You'll probably sell the 2.32 1st toploader for more than the cost of the T5
My math shows 4.56 gears with 28" tall tires will be doing 3557 rpm at 65 mph. (1-1) trans final ratio. That is not a friendly rpm for a long highway drive. 3830 rpm at 70 mph. Another consideration is what your trans ratios are. A wide ratio top loader with 2.78 first gear with feel like a granny gear and you could probably take off in second. The close ratio with a 2.32 first gear would be an improvement. Just a thought
I would go with a 3.70 gear and find another carrier to build and keep the 4.57 for when you feel froggy. Only takes about an hour to change the chunk. I used to run a 65 Comet and change the chunk on Friday night to a 5.43 and then on Sunday night to a 3.00 to drive to work all week. My buddy had a gas station and I would use his lift. I had a Holman and Moody 289 that had a 2 piece intake so I could run dual offset quads on the weekend and a single during the week also. Used to love the AHRA. They let me run M/Stock optional with that set up.
My Dad used to run a 3.50 gear in a Model A coupe he put together with a 351c and an automatic. With 30" tires on it,it was the biggest turd you've ever seen out of the hole,but would run 120mph without a fuss. What fun is that??? Those 30" tires will make that 4.57 gear feel a lot more like a 3.42 or a 3.73 that you may be more used to in a musclecar with a more conventional 26-27" tall tire. With a little tiny,high winding motor that loves to rev and doesn't make much torque,you're gonna wreck the whole deal if you put a tall gear in it.You said yourself,there are no long trips planned,just having fun around town. Just give it a try as-is. You're gonna love it! Scott Sent from my iPhone using H.A.M.B.
As others have said change the trie size to a 30" diameter and try it. Your 289 is not going to be very happy under 2500rpm on the highway. I drove. 68 bronco with one for about a decade as a daily, it had a sweet spot at about 2800 and would get 20+ mpg at that. Lugging it around in overdrive or with real high gears will make it feel like a slug.
I'd try it with what you have got. The overdrive transmission or extra third member are great ideas. Pete
If you have a true close ratio toploader, it will have the 2.32 first. A 4.56 rear is a good match to get launched without a lot of clutch slipping. A combined ratio of around 10:1 is a good ballpark for 1st, with a typical sized tire. If you're not doing road trips, you don't need overdrive. Just use what you have. If you have the standard toploader with 2.78 first then you could use something in the 3.90-3.50 range. For comparison, most T5's used in late 80's-90's Mustangs had a 3.35 first combined with a 3.27 rear for an overall ratio of 11:1
I am running 3.70 gears with about 29 inch tall tire, at 75 MPH it is in the 3200 RPM range, I guess if you never leave a city environment that would be great, I guess I am used to my daily driver that tachs 1200 or 1500 RPM at 70. Back in the 60's a friend bought a 64 Chevy Biscayne, police special, 300 HP brand new, he stuck 456 gears. I rode less than an hour with him and it took forever to go 45 miles at 55 MPH, it sure ran good though when I started banging that four speed
I sincerely think you will have the time of your life with it running those gears and that engine combo. A 271hp 289 in a light car like a model A,with a 4-spd and a 4.57 gear will be magic! Keep us updated!!! Scott Sent from my iPhone using H.A.M.B.
Knowing the engine power characteristics, type of driving to be done with the car, transmission final ratio, tire diameter, and using an online calculator would be my recommendation. Or ............................... write the ratios on pieces of paper and throw darts.
Knowing the engine characteristics: -small cubic inch,short stroke,low torque,6000rpm power peak in stock form (may be higher due to aftermarket cam(?) and tunnel ram),but stock hi-po exhaust manifolds will limit power Type of driving to be done with the car: -Local cruising,car shows etc.No highway driving. Transmission final drive ratio: -Ford close ratio top loader 4-Spd,1:1 Tire diameter: -He's saying 28",but I think he could take advantage of a 29" or 30" tire if he has room. All the info was in his initial intro....He just needs to throw some tires on the completed car,make sure a competent carb guy gets into those Holleys,and take that thing out and rip around town for an evening,to see if it's his cup of tea or not. Either he'll be the happiest cat in town,or he'll think those gears are too deep.Either way,without trying it,for a baseline to have something to compare to,he's kinda putting the cart before the horse. After all,it was a cool enough combo for somebody to build it that way,and drive it that way back then,right...? And a small block Ford with a tunnel ram and deep gears and a stick trans is what I've got in the garage right now. Betcha $1 he loves that thing. Scott Sent from my iPhone using The H.A.M.B. mobile app
From the response here it seems to me the guys who say change the ratio have obviously never driven a 289! Let it rev! Get used to shifting at 4500rpm not 2200. I have a full roller 289 built on a 90's 5.0 block and heads with an early edelbrock torker intake sitting in the garage right now. Destined for my 34 ford project. I have a 4.56 rear axle and am on the hunt for a top loader now. 30" tall cheater slicks and it should be all sorts of fun. According to my favorite ratio calculator 6000rpm is 117 mph and 60 mph is a very reasonable 3575 rpm. Not something you want to drive across the country but a lot of fun locally.
I'm running a 4.30 rear with a 29.5" tire and a full manual turbo 350 with a 383 sbc. No, it"s not for long hauls but it's fun as hell terrorizing the town and back roads. I don't know if the OP is running rear fenders or not but 28" rear tires sounds too short for a model a
289's are made to rev. The short stroke just makes it an almost perfect match for the 4.57's. I drove my 289 4 speed from Florida to Michigan with 4.11's and a 26 inch tire and never thought twice about doing it. Cruising at 3 grand just sounded good.
I didn't see where this was addressed after re-reading through all of the posts again, if it was then I missed it. YES you need a vent! If you don't vent the rear end it could due to expansion of the gear oil cause any seals to begin leaking possibly soaking your rear brakes and rendering them useless when you least expect it and really need them.
As to your vent tube, some rears used a hollow bolt to secure the brakeline 'Tee' to the axle tube up near the center section. It acted as the vent, check yours to see if it is plugged or has been replaced with a solid bolt. Sometimes goo with accumulate on top of it and disguise what it really is.
My daily driver f1 has 4.56 gears and 750 16 tires (30-31 inch diameter) and I find that a great ratio for tall tires and a non od tranny.... Originally had 3.50s ...ate up clutches too quick.. then 3.92s.....was still downshifting all the time. I now have 4.56s in it for 8 years and over 100,000 miles including some LONG trips. And yes you need a vent...
IMO, leave as is, get it running, drive it around and see how it works out. it's easy to pull center section out and change later, Get her running , Enjoy !
The housing has one hole with a solid bolt ( no hole in the bolt) that is holds the brass tee for the rear brake line . The bolt hole is too small for the typical vent tube . So i will just tap a larger hole so i can put in a vent. Thanks Ron
It is a true close ratio trans. The casting #s HEH T Date code is aug 1964 I will be keeping this set up Thanks Ron
Your housing is vented. In the lower left photo, your 3rd knuckle is right in front of it. Has just a tiny hole and that's all it needs to keep from pressurizing the housing. Put a short hose on it that loops over 180 degrees so water on the road can't get in and you're done. It's worked fine for 58 years and will continue to do so if you let it.
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