3.23 or 3.55 Behind a 318

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It’s about balance. Gear ratio coupled with tire size for what your intended purpose is. To that end....

I have found a stock tire A body and 3.23 gears are a good performer. The same goes for 3.55’s though a stock tire tends to have the engine buzzing a tad higher than I like so a slightly larger tire is used.

With this kind of set up, the cam size is on the small side. 224@050 is about as big as I’d go. 230@050 acceptable. Though at this duration, I’d like at least 3.91’s and a min. of a 26 inch diameter tire.

If your building a street stripper, give it the big cam, converter and gears, then proceed to rip up the streets.
 
I don't think anyone's asked what transmission you're running? If it's an over drive for instance, you can stand a 4.10 and never look back.
 
Just went from 3.55's to 3.91's in my dart sport 360. Haven't driven it yet. Also doing cam and intake swap so not sure how it will feel after!
 
Your driving on I 75 in an old car on the weekend. You better stay in the slow lane!

We've got a caravan of cars (at least the 4 below) driving up. We're all heading out Thursday morning.

St Ignace Locals (Steve-Mike-Dan-JohnV.jpg
 
I'm drooling over that Black Bandit!
I looked for 2 years for a clean '63 - '65 B Body....finally gave up and bought a '68 Dart which is just fine!
 
I have 3.23 in my Duster with 28" tires, it was the only set of gears I had when I put the rear together, way too high for around town use, but work good on the highway.
I have since built/purchased 4.10, 4.30, 5.38 gears, but most likely will run the 4.30 because it is basically an around town car.
The 5.38 I bought because it was a complete sure-grip unit, that I most likely may end up putting some 3.73 gears in.
 
It’s about balance. Gear ratio coupled with tire size for what your intended purpose is. To that end....

I have found a stock tire A body and 3.23 gears are a good performer. The same goes for 3.55’s though a stock tire tends to have the engine buzzing a tad higher than I like so a slightly larger tire is used.

With this kind of set up, the cam size is on the small side. 224@050 is about as big as I’d go. 230@050 acceptable. Though at this duration, I’d like at least 3.91’s and a min. of a 26 inch diameter tire.

If your building a street stripper, give it the big cam, converter and gears, then proceed to rip up the streets.

No it's not. What a gheyed out answer. Balance. My big old butt. It's about haulin ***. lol
 
i think everybody is hoodwinked by 3.55's
i never found them to be a good quarter mile gear or cruising gear.If your cam is too big
and your tires too tall then a jump to 3.9's or 4.10's would be required.
 
No it's not. What a gheyed out answer. Balance. My big old butt. It's about haulin ***. lol
Narrowed visioned. When it’s a driver, it’s balance.
When your out having at it, it’s the regular montra.
Mo-cam, mo-converter, mo-gear, mo-tire, mo-cam and of course, Mo-cowbell!

RRR. Do you remember? I have 4.88’s in my Duster as we speak? Just checkin....
 
grab a 92-95 non electronic OD 518 the one with the 3 pin connector
then run 3:55 (if a lot of highway) or 3.92-4.10 gears
as said above depends on usage and cam
if you have the HP cam definitely go for the lower gears
 
I'm drooling over that Black Bandit!
I looked for 2 years for a clean '63 - '65 B Body....finally gave up and bought a '68 Dart which is just fine!

My buddy found it online in Raeford, NC. Heck of a weekend trip to get it!
 
It's complicated.
As to the starter gear,it's all about effective gear. From 3.23 to 3.55 is about 10% and from the tallest tire that will fit in an A-body being about a 28 then 10% less is 25.2 or about the smallest you would likely use. So in this case the tall tires with 3.55s would cruise at about the same rpm as the shorts with 3.23s. The effective gearing is the same.
After that, it's all about the stall-speed.
If your TC stalls at 1800 and your engine makes 140 ftpounds there, then with 3.55s it will effectively put 140x2.45x3.55x24/28=1044 ftlbs to the pavement. If you increase the stall and find 10% more torque, say 154ftlbs, then you can use 3.23s for 154x2.45x3.23x24/28=1045 ftlbs. And your car will take off from zero mph, about the same.
Of course 1045 to the pavement,is a very lo-performance take-off.
But say you put a 2800TC in there, and still 28s and 3.55s, and a 4bbl and upped the compression, and found yourself with 320 ftlbs, then;
320x2.45x3.55x24/28 then you get 2385 tire-frying ftlbs.... Yes still with 3.55s. Now, the guy in the next lane with a lo-Compression 360, a big lumpy cam, and a very low-stall, with 3.91s, might put out 280ftlbs; and so at zero mph, might be putting down 280x2.45x3.91x24/28=2299 to the pavement.
So, as you can see, it's complicated.
Gears can make or break a combo, but stall can totally choke it, and there is about a 10% variance in "effective TM" Torque-Multiplication, going from tallest to smallest tires.
Once the car begins to move, then it's a whole nuther story.
 
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Im in the process of putting in 3.55's but i running 18's with 25" tall tire and a TKO 600 5 speed, Im not sure I made the right choice the gears are
2.87 1.89 1.28 1.00 0.64 reverse 2.56
curios how it will act.

One other thing to consider and why i went with a OD is here in SD most of the interstates are 80 MPH
 
Im in the process of putting in 3.55's but i running 18's with 25" tall tire and a TKO 600 5 speed, Im not sure I made the right choice the gears are
2.87 1.89 1.28 1.00 0.64 reverse 2.56
curios how it will act.
Behind a 408 I take it? Yup with that OD I would have went with 4.10's unless your looking for top speed.
 
Yep behind a 408, i figured with the 25" tall tires I would be happy with 3.55's I guess I will wait and see.
 
Narrowed visioned. When it’s a driver, it’s balance.
When your out having at it, it’s the regular montra.
Mo-cam, mo-converter, mo-gear, mo-tire, mo-cam and of course, Mo-cowbell!

RRR. Do you remember? I have 4.88’s in my Duster as we speak? Just checkin....

I know. I'm just messin with my friend. lol I can do that, right?
 
Not sure Ive read what the intended use/uses are for the car. Until then, we are are pissing in the wind.
 
Im in the process of putting in 3.55's but i running 18's with 25" tall tire and a TKO 600 5 speed, Im not sure I made the right choice the gears are
2.87 1.89 1.28 1.00 0.64 reverse 2.56
curios how it will act.

One other thing to consider and why i went with a OD is here in SD most of the interstates are 80 MPH
10.19 starter gear.......60 @ top of second is 5412.......80=2444.......Road gears are;
10.19-6.71-4.54-3.55-2.27; with splits of .66-.68-.78-.64od
With the right cam and cylinder pressure,in a stroker,on the street; IMO, that's gonna be as close to perfect as can be. My 367 wouldda liked 3.73s, and third couldda been a lil closer to second;but in your stroker, I think it will be very very nice.
Years ago,I followed a Corvette for awhile, on the Interstate thru the Dakotas. We mighta been shuffling along at buck20ishI forget. I had a 1.97 final drive, so 80 woulddabeen 1900. My Barracuda got pretty noisy with wind ripping over it so we had to eventually let him go. After a while, even the earplugs were not helping anymore.
Point is; nice roads.
 
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