These are spot on. Dad has 3.55 with 275 60 15 on his barracuda. I now have 2.94 with same 275 60 15 on the Demon. Exact numbers we are seeing for 28" tire.
Overdrive or don't worry about it? !
- Thread starter MrJLR
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These are spot on. Dad has 3.55 with 275 60 15 on his barracuda. I now have 2.94 with same 275 60 15 on the Demon. Exact numbers we are seeing for 28" tire.
K.O. SWINGER
Meeting in the alley since 1976
I'm all about 323s they're beautiful highway gear that's why they was a standard gear in roadrunners 340 swingers super bees cudas etc and as mentioned by 318 willrun with all the additional torque of a 4-in crank bottom end will be no problem. The 323 were used when the speed limit was 70 miles an hour very similar to what people are going today. And a little bigger tire if you even want more.of course camming will be a consideration also I didn't see that mentioned in the previous post.
abodyjoe
Well-Known Member
here.. play around with tire size, OD units and gear ratios.. if the gear isn't listed just type it in yourself and it will still calculate correctly.. Speed/Tire/RPM calculator
DesertRat
Leading edge boomer
With that torque monster motor you can use 3:23 or 2:94 and still have an asphalt ripper. Use a shur-grip. My Barracuda has 3:73 with 28" tires and GV. With stock converter and my 904 I'm at 2400 rpm at 70 mph. I'm building a car now that will have 400 foot pounds torque with a T-10 4speed and 3:23 track lock and 28" tires.
abodyjoe
Well-Known Member
Last time eh....yeah the check is in the mail. If you are a serious enthusiast
You will always be building something new, even if it is in your mind.
Drive the piss out of it. YOLO. Sure your engine will wear out quicker, no problem, but $300 inparts to refresh it.
Find out out what will be the most pleasing to you. Then make changes. Most of what I’m doing is cruising, some spirited road driving, and stoplight to stoplight. If I want a long term cruise I’ll drop the 2.76 in and take the 3.91 out. I’m guessing that by the time you fit an OD in the car you’ll spend $2500. 2.76 and 2.94 are cheap you should be able to get one for under $100. Check out some tire/axle/rpm calculators
You will always be building something new, even if it is in your mind.
Drive the piss out of it. YOLO. Sure your engine will wear out quicker, no problem, but $300 inparts to refresh it.
Find out out what will be the most pleasing to you. Then make changes. Most of what I’m doing is cruising, some spirited road driving, and stoplight to stoplight. If I want a long term cruise I’ll drop the 2.76 in and take the 3.91 out. I’m guessing that by the time you fit an OD in the car you’ll spend $2500. 2.76 and 2.94 are cheap you should be able to get one for under $100. Check out some tire/axle/rpm calculators
abodyjoe
Well-Known Member
sure tires are easier to do then a center section. but is only 200 rpm really worth it? i say no. barley notice that.. 500-1000 rpm ok.. i can only speak for myself.. i don't want to bother doing either (tires or center section) . i want to go out to the garage, start the car and go where ever i want whether its 5 miles or 300 miles. i can't be bothered changing crap just for a drive.. no matter what you do there will be a compromise so choose what side of that compromise you want to be on and go with it...
best of all worlds woudl be OD of some sort but thats going to cost 2500+ dollars most likely but it will drive like you want. the only compromise going OD is the money...
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Despite running a 440 with tunnel ram and 1:1 linkage on the 660's, 2400 stall, I may just keep the 2.94s. At least until the Charger is done.
My vote is on the 2.94 rear gears for your driving experience. They came factory on my '69 Satellite 318 with the 8 3/4. Had a 727 trans in it too. This has been my favorite driveline combination.
Added a 4 bbl to the factory 318, pulled the B Body car around just fine, with a nice 600 cfm 4 bbl to play with at all speeds. Not over-reving at 75 mph freeway speeds. The lightweight Torq-Thrust II wheels helped hugely with less rotating mass to spin up every time you take off from a stop.
Factory single exhaust system, and still got 20 miles per gallon even when playing with the 4 bbl.
So if 2.94s can pull around the larger B Bodies just fine (I am not interested in doing burn outs, just good all around driving experience). Just think how the added torque of the stroked 318 will walk it around no problem.
15" Torq Thrust wheels with these tire sizes. No need to swap rear end chunks.
Added a 4 bbl to the factory 318, pulled the B Body car around just fine, with a nice 600 cfm 4 bbl to play with at all speeds. Not over-reving at 75 mph freeway speeds. The lightweight Torq-Thrust II wheels helped hugely with less rotating mass to spin up every time you take off from a stop.
Factory single exhaust system, and still got 20 miles per gallon even when playing with the 4 bbl.
So if 2.94s can pull around the larger B Bodies just fine (I am not interested in doing burn outs, just good all around driving experience). Just think how the added torque of the stroked 318 will walk it around no problem.
15" Torq Thrust wheels with these tire sizes. No need to swap rear end chunks.
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Sitting here on the patio on a pleasant, breezy Sunday morning is a great time to spend other people's money.
I think you should stay with the 3.55 and add OD. It just makes for a more enjoyable driver. I find it better to do things like this right from the beginning instead of later and it sounds like you are going to keep this car a long time. Like updating or adding a bath to a house, an OD adds value to your car if done properly. You may not get every dollar out of it but it's something. And everyone raise your hand if you think gas prices are going to drop again. The present administration has made it clear they are going green. All they have to do is raise federal taxes substantially to cut emissions.
GV is a proven product but don't forget about the driveshaft change.
All Mopar would mean a swap to a newer 4 speed OD.
Nobody has mentioned the bolt-in automatic OD offered by Silver Sport Transmission. It's based on a modified GM trans. Another alternative.
I think you should stay with the 3.55 and add OD. It just makes for a more enjoyable driver. I find it better to do things like this right from the beginning instead of later and it sounds like you are going to keep this car a long time. Like updating or adding a bath to a house, an OD adds value to your car if done properly. You may not get every dollar out of it but it's something. And everyone raise your hand if you think gas prices are going to drop again. The present administration has made it clear they are going green. All they have to do is raise federal taxes substantially to cut emissions.
GV is a proven product but don't forget about the driveshaft change.
All Mopar would mean a swap to a newer 4 speed OD.
Nobody has mentioned the bolt-in automatic OD offered by Silver Sport Transmission. It's based on a modified GM trans. Another alternative.
jos51700
Green Bearing thread connoisseur
3.55's with a factory 518OD is a great combo with the 318 in my Dakota.
Do the math, add the overdrive and drop the rear gearing as much as you can. You'll be glad you did. The actual OD method isn't as important as adding it.
And you said 'hard on'.....
Do the math, add the overdrive and drop the rear gearing as much as you can. You'll be glad you did. The actual OD method isn't as important as adding it.
And you said 'hard on'.....
R4Sedan
Larry
Jeff, My last Challenger I built had a 318 Stroker it had 2:94 sure grip and it would fry the tires. Due to all the Torque. Or you could do best of both world's put a 3:91 and order up a 5 or 6 Speed from Silver Sport. It would look cool with a stick coming through the console.
Tell me about your t/a tires. I just bought a set
They are my favorite Classic Car tires, drive and ride nice. The right sidewall height for the "Classic Car" back in the day look.
I turn the white lettering in to the inside. Like the lines of all classic cars without having to read the tires or advertise for tire companies.
The set I have posted above had the special 65 series for the fronts, not too tall and not too short. This combo gave a 1" rake from the back of the car to the front in tire size. On 7 x 15s on the front and 8 x 15s on the rear of that b body. The car had the Monroe Style air shocks on it that were 30 years old still holding air, so it was nice to dial in the ride height of the car without being too stiff. Cranked the front torsions up a couple turns to help get the car back up to stock riding height after 40 years, reset the toe in after so it would not scrub the new tires after the height adjustment.
Was a manual steering car too, so that helped with the performance a bit too not having to run a power steering pump, clutch fan too, that also helps too.
That's funny... Cruising the highway.... In California.... what, get all the way up to 35 sometimes.... rpms must be up to 1700 by that speed!
67Dart273
Well-Known Member
THIS, OP you are under/ over / around thinking this. There were Gigans of these cars built and DRIVIN ON THE HIGHWAY. Put some decent diameter tires on it and anything 3.55 or higher geared and drive it
moparmat2000
Well-Known Member
Mr JLR , Check out my build thread 67/68/69 cuda dilemma. I am installing a 42RH out of a 1992 V6 Dakota. On the last several pages of this thread, I left a blueprint of sorts in lots of pictures, and information for others to follow to do a similar install. This allows you to run your stock 3 speed console shifter if equipped. I even figured a way to make a stock cable kickdown setup work with a mix of ram van and dakota parts. With a 25" tall tire and 3.73s we will be running, when O/D and lockup are switched on, this car will run 2,400 rpm at 75 mph. Off the freeway, you turn the OD and lockup switch off, and it's a regular torqueflight 3 speed.
Years ago I flew toOakland and bought a wonderfully done 67 Cuda, 383 4 speed 2:94 gars. Drove it back to Missouri, Sure, I was used to heavier B bodies with 383s or 440s, 4 speed cars with 3:55's, but I got used to getting that Cuda rolling with that hiway gear. It was a great ride!
Looking like Gear Vendors is the best solution for my application. ...
Jeff
Jeff
TT5.9mag
Two atmospheres are better than one
The only thing I can add is the overdrive will be the single largest reason you drive your new hot rod. It’s the best single modification you can do to help enjoy your car. If this is your “dream build” do not compromise on the trans. 100% if you have any plans of driving the car put an overdrive in it.
To actually answer your question I have not seen answered yet, it will in no way shape form or fashion hurt or otherwise shorten the life span of your engine to run it at 3500 RPM. No way. No how. That said, it'll burn a lotta gas.
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