I have a 1950 Styleline Deluxe that I' swapping in a stock rebuilt 283 and a 200r4 trans. The differential I picked up (69 Camaro 10 bolt) is at the rebuilders. They called and told me ir has 2.73 gears. I'm worried that they might be too tall. He said it would cost an additional 600 bucks to put a lower gear in it . The car is gonna be just a cruiser. My question is will the 2.73 rear gear 283/200r4 be a decent street/highway combo? Or should I start selling blood to put a different gear in it?
What size tire? A guess based on experience, at least 3.23 would make a nice cruiser. Or slap a T350 in and keep the 2.73.
I have a 62 Impala w a 283 and 200R4 14" wheels 3:36 gears tried 3:08 both worked in town and highway cruising I would try the 2:73 they came from factory 2:73 and 200R4 in early 80s G body cars
Try it and see. You can always reserve shifting in OD until you need it. Here's a comparison for you. I just got back from a trip this weekend. The Produce truck has a 350 SBC/200 4R and a 3.50 rear gear. it cruised at 80 at 2500. That's with a 235 75/15 28.5" tall tire. Mine has a 3.5" stroke, you will have a 3" stroke but a higher gear. I would try it before dumping a ton of money into it.
The 2:73 gears and the 283 will not like each other, not to mention the overdrive. 283’s like to wind and your combination will not let it unless you plan on making passes at the big salt lake bed. You’ll need to change something of your three components (engine, transmission, rear gear). r Sent from my iPhone using H.A.M.B.
Like raven said. 283's like to spin. It won't like the 2.73 without the OD. Performance and fuel economy will suffer.
0.67:1 overdrive x 2.73:1 rear gear = 1.829:1 overall ratio. It might work, might also try finding a tire with less than a 24" height too. Maybe a computer controlled ignition & fuel injection systems. I'd personally think you're heading into "it drives like a slug" territory. -Dave
Even with a 26" tire you will be at 1650 at 70 mph over drive will probally only work going down hill.
A quick Google search tells me the stock tire size for your car is a 670-15 and the OD ratio for a 200R4 is .67. Coker says their Firestone 670-15 diameter is 28.5 inches. MPH x Rear Gear Ratio x 336 / Tire Height x Overdrive = Cruise RPM 65 x 2.73 x 336 / 28.5 x .67 = 1,401 RPM 65 x 2.73 x 336 / 28.5 x 1.00 = 2,092 RPM (no overdrive) Like someone said earlier, that 283 will like to rev, so you'll need to change something in your combination. In fact, the 283 with the 2.73 rear gear would cruise really well at highway speeds without the overdrive.
Here's another idea. Try driving it on the highway in 3rd gear, don't shift into overdrive. If you like the way it drives in 3rd between 60 & 80mph then the thing to do would be a set of 4.10:1 axle gears. Your overdrive would be right back to where the 2.73:1 gears were in 3rd. Your starts from a stand still will be more spirited also, with nothing lost out on the highway. Or, if it still seems to be buzzing in 3rd with the 2.73:1 gears on the highway then you might consider swapping to rear gears in the 3.2 to 3.7 range to get the engine to slow down on the highway in overdrive. And you never said if your 283 is basically stock, or if it's been modified as some of the HAMB hoodlums have been known to do. Souping up a mill will effect where the engine likes to run, RPM wise. -Dave
I have a 700r4 behind a 350. Just slightly different OD. I had 2.79 rear gears with 28" 235/75 tires. I could not get it in 4th gear until at least 55 mph. You can drive it like that and just use 4th and OD on the highway. It's not too bad. Then I put 3.80's in it. It's a lot better, but I wish I had put 4.11's in it. I still can't just put in 4th/OD and drive it. It wants to lug in town. Your 283 is going to want more than that.
This is why I mentioned keeping the 2.73, and swap to a T350. Any rear ratio under 3.23 will be a dog on the highway, with constant downshifting due to the low torque of a 283. I set up a street rod sbc 350 471 blower with 4.10's and a 700R4. Runs awesome on the highway with 29 inch tires.
1st gear in a T350 is 2.52. 1st gear in a 200-4R is 2.74. Use the 200-4R and don't put it in overdrive. It will work just fine. Sent from my SAMSUNG-SM-G900A using The H.A.M.B. mobile app
Pretty much had your setup san overdrive in a 51 sedan. Stock 307, TH350, and a 2.73. It was just about right at 70mph. It would be super sluggy with an overdrive. I would want a 3.73 at least for a cruiser. My current setup in the same car is T5 and 3.42. Should work out similar, as the T5 overdrive ratio is different. As said, you could run it in 3rd and get the same thing.
Another vote for 3.73's, I had a 302/AOD with 3.50 rear gears, and OD was only useful downhill, with a tailwind. That stock 302 had the same short stroke as your 283, and is fairly comparable. I know there are folks running 3.08 with overdrive, and actually have one outside, but it is a longer stroke 6 cylinder, all in by 3200rpm.
I work on the rule of thumb that engine rpms should be between 1800 to 2100rpm @ 60mph. My:- 35 Chebby, 5lt SBC / 700R and 235:75:15 tyres with 3.54:1 rear axle cruises around 2k rpm @ 60mph; and OT DD has identical size tyres with 3.73:1 and has slightly higher rpm @ 60mph. IMO 2.73:1 is not suited to OD transmission, you're better with a 3pd auto (TH350) with that ratio. Don't go to a TH400, way too much parasitic drag for a 283. Might as well use a 2sp auto (PG).
Would it hurt the 200r4 to run in 3rd gear all day? Since the r4 has a 2.74 1st gear and 2nd 1.57 gear compared to the 350 at 1st gear 2.52 and 2nd 1.52, wouldn't the r4 help my lower end? Or am I overthinking this? Thanks for all the comments and info everyone.
I'm not sure about the 200r4, but the 700r4 when in 3rd manual has engine braking. Meaning when you let off the gas it doesn't coast. The 200r4 is probably the same.
You could however in the end, 3rd gear in the 200R or 700R is the same as any other 3 speed auto with 1 to 1, eg. T350 or T400. I see no advantages in having the additional 4th gear (OD) if you can't / don't use it. Don't go any further with the 10 bolt, sell it off rather than throw good money after bad. A cheap alternative is a junkyard 8.8" Ford Explorer with 3.73:1, it will allow you to use a 200R as designed; day in, day out. https://therangerstation.com/tech_library/Ford-8_8-axle.shtml
Normally a 3.50 rear gear will work best with an overdrive. The 3.73 mentioned earlier would work too
The engine has to be in a good rpm range to make adequate power & torque with the ratios in the driveline. Here is a calculator that will give an idea of the rpms in each gear vs speed. The ratios for the gears are available so it is possible to see what the speeds would be for each gear & rpm range. This calculator will let you calculate the rpm at 60 mph or 70 to see if that is comfortable in overdrive. The 3.55 & 3.73 ratios are reasonable ratios with overdrive. Changing the rear ratio will let the engine run properly through all the gears to be a better performer, a friendly driver and a quieter drive at highway speeds. Make full use of the possibilities with the transmission and be happy. The overdrive with the right rear end ratio will pay for the change with the fuel savings. https://www.teambuick.com/reference/calculators.php
No those gears will not be a good idea. You want a 3.73:1 gear at the tallest and it will actually work best with a 4.11:1 gear.
The 200r4 does the same thing as far as the engine braking. You’ll also need to think about a switch or vacuum/speed sensor to activate the lockup converter at speed. If not you’ll burn up your tranny. They are a great transmission when used with the proper components. r Sent from my iPhone using H.A.M.B.
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