[C2] 4.11
Thread Starter
Burning Brakes
Joined: Jul 2009
Posts: 1,240
Likes: 294
From: ESCONDIDO CA
2025 C2 of the Year ('63 and '67) Finalist - Unmodified
C2 of Year Finalist (appearance mods) 2019
4.11
I've been crawling around under the '63 for a few weeks now. Trailing arms are away at Van Steel for a rebuild. Half shafts and drive line have bee outfitted with new universal joints and waiting to be reinstalled. Yesterday I pulled and replaced the bushing and seal from the rear of the T10 tranny.
As I was lingering beneath the beast, very pleased with my success, I decided to spin the differential. First I thought I would try to determine the condition. Of course, I couldn't tell much but then this happened--it took exactly 4.11 turns of the drive shaft to obtain one full turn of the half shaft. Yup, I was surprised. Most fuelies were equipped with 3.70 differentials.
What I know about this car is, it's all numbers matching original. It was bought from a San Diego dealer (Campbell Chevrolet), and it's a one owner car until I bought it 2 years ago. And the owner did not race the car-not ever. One more thing, the original exhaust had welded-in cut-outs.
Somebody from Campbell Chevrolet (my guess) added a few miles to this car a quarter mile at a time...wish I knew more!
As I was lingering beneath the beast, very pleased with my success, I decided to spin the differential. First I thought I would try to determine the condition. Of course, I couldn't tell much but then this happened--it took exactly 4.11 turns of the drive shaft to obtain one full turn of the half shaft. Yup, I was surprised. Most fuelies were equipped with 3.70 differentials.
What I know about this car is, it's all numbers matching original. It was bought from a San Diego dealer (Campbell Chevrolet), and it's a one owner car until I bought it 2 years ago. And the owner did not race the car-not ever. One more thing, the original exhaust had welded-in cut-outs.
Somebody from Campbell Chevrolet (my guess) added a few miles to this car a quarter mile at a time...wish I knew more!
Le Mans Master
Joined: Sep 2009
Posts: 9,151
Likes: 481
From: "You may all go to Hell- and I will go to Texas- Davy Crockett
St. Jude Donor '12
Back in the day, we called em dumps. You would go down to the industrial supply house and buy a set of 2 1/2" pipe nipples with screw on caps and have the muffler shop guy weld em on. Don't know how much they helped, but headers hadn't been mass produced yet, so that was what we all ran.
Last edited by vettsplit 63; Mar 2, 2018 at 09:57 AM.
Melting Slicks<br><img src="/forums/images/ranks/3k-4k.gif" border="0">
Joined: Mar 2008
Posts: 3,274
Likes: 2,219
From: Colorado Springs Colorado
2024 C2 of the Year Finalist - Modified
2023 C2 of the Year Finalist - Unmodified
I have a friend with a ‘63 split window fuelie that is very original. He bought it about 15 yrs ago from his now ex-mother in law when his father in law (original owner) passed away. It has a 411 rear end Which came in the car when new.
Team Owner
Joined: Apr 2008
Posts: 31,785
Likes: 2,395
From: Middle TN by way of KY, OH, VA, IL, CA, FL, NY, SC, HI
The two-digit alphanumeric code stamped on the bottom of the diffy indicates which rear gears were installed in it at the factory.
Mine are 4.11s (correctly stated as 4.11:1). IIRC, the code is AQ.
Another way to tell you have 4.11s is the engine will spin at 3000 rpms at 60 mph with the standard sized tires.
Mine are 4.11s (correctly stated as 4.11:1). IIRC, the code is AQ.
Another way to tell you have 4.11s is the engine will spin at 3000 rpms at 60 mph with the standard sized tires.
Last edited by Easy Rhino; Mar 1, 2018 at 10:16 PM.
Team Owner
Joined: Nov 2005
Posts: 28,217
Likes: 2,872
From: Beach & High Desert Southern California
The two-digit alphanumeric code stamped on the bottom of the diffy indicates which rear gears were installed in it at the factory.
Mine are 4.11s (correctly stated as 4.11:1). IIRC, the code is AQ.
Another way to tell you have 4.11s is the engine will spin at 3000 rpms at 60 mph with the standard sized tires.
Mine are 4.11s (correctly stated as 4.11:1). IIRC, the code is AQ.
Another way to tell you have 4.11s is the engine will spin at 3000 rpms at 60 mph with the standard sized tires.
For the OP: The assembly date and ratio code is stamped under the pumpkin near the rear cover mating surface. My original 63' is also a 4.10.
I have a spare very late 63'/early 64' pumpkin with a 4.56 ratio code. Some cars were ordered to launch.
4.10 gears were fairly common on the SHP & FI drive trains. The buyer of a solid lifter engine option didn't worry much about fuel mileage or singing down the road at 4000 rpm, they wanted to use that rpm to beat the other cars off the line and never look back.
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
Le Mans Master
Joined: Sep 2003
Posts: 8,812
Likes: 2,029
From: eastern NC
I've been crawling around under the '63 for a few weeks now. Trailing arms are away at Van Steel for a rebuild. Half shafts and drive line have bee outfitted with new universal joints and waiting to be reinstalled. Yesterday I pulled and replaced the bushing and seal from the rear of the T10 tranny.
As I was lingering beneath the beast, very pleased with my success, I decided to spin the differential. First I thought I would try to determine the condition. Of course, I couldn't tell much but then this happened--it took exactly 4.11 turns of the drive shaft to obtain one full turn of the half shaft. Yup, I was surprised. Most fuelies were equipped with 3.70 differentials.
What I know about this car is, it's all numbers matching original. It was bought from a San Diego dealer (Campbell Chevrolet), and it's a one owner car until I bought it 2 years ago. And the owner did not race the car-not ever. One more thing, the original exhaust had welded-in cut-outs.
Somebody from Campbell Chevrolet (my guess) added a few miles to this car a quarter mile at a time...wish I knew more!
As I was lingering beneath the beast, very pleased with my success, I decided to spin the differential. First I thought I would try to determine the condition. Of course, I couldn't tell much but then this happened--it took exactly 4.11 turns of the drive shaft to obtain one full turn of the half shaft. Yup, I was surprised. Most fuelies were equipped with 3.70 differentials.
What I know about this car is, it's all numbers matching original. It was bought from a San Diego dealer (Campbell Chevrolet), and it's a one owner car until I bought it 2 years ago. And the owner did not race the car-not ever. One more thing, the original exhaust had welded-in cut-outs.
Somebody from Campbell Chevrolet (my guess) added a few miles to this car a quarter mile at a time...wish I knew more!
No offense intended, but it was amazing what husbands did to their cars and with them back then, when wives weren't looking...
I bought my '63 in 1969 right after the original owner traded it in on an MGB-GT... it had 3.70 rear gears and also had welded in cut-out... maybe they were a special COPO option.
Good luck... GUSTO
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Thread Starter
Burning Brakes
Joined: Jul 2009
Posts: 1,240
Likes: 294
From: ESCONDIDO CA
2025 C2 of the Year ('63 and '67) Finalist - Unmodified
C2 of Year Finalist (appearance mods) 2019
Famous last words...
No offense intended, but it was amazing what husbands did to their cars and with them back then, when wives weren't looking...
I bought my '63 in 1969 right after the original owner traded it in on an MGB-GT... it had 3.70 rear gears and also had welded in cut-out... maybe they were a special COPO option.
Good luck... GUSTO
No offense intended, but it was amazing what husbands did to their cars and with them back then, when wives weren't looking...
I bought my '63 in 1969 right after the original owner traded it in on an MGB-GT... it had 3.70 rear gears and also had welded in cut-out... maybe they were a special COPO option.
Good luck... GUSTO
Like I said, would be nice to know more. The history of these old cars is always part myth, lies, and loving memories-even for the original owners. Part of what makes the hobby so much fun!
Race Director
Joined: Apr 2015
Posts: 17,571
Likes: 3,460
From: Fresno California
Famous last words...
No offense intended, but it was amazing what husbands did to their cars and with them back then, when wives weren't looking...
I bought my '63 in 1969 right after the original owner traded it in on an MGB-GT... it had 3.70 rear gears and also had welded in cut-out... maybe they were a special COPO option.
Good luck... GUSTO
No offense intended, but it was amazing what husbands did to their cars and with them back then, when wives weren't looking...
I bought my '63 in 1969 right after the original owner traded it in on an MGB-GT... it had 3.70 rear gears and also had welded in cut-out... maybe they were a special COPO option.
Good luck... GUSTO
Back on topic, if my car had 4:11 gears, I'd pull the third member out and swap in a 3:36!
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
Not Corvette but 4.11 related...........................
When I was a Junior in high school, my mother bought a new car. She didn't know whether to buy a '60 Corvair or a '60 Studebaker Lark. I strongly encouraged her to buy the Studebaker and oh yeah Mom, while yer at it, buy the V-8 model. I've heard the six bangers use a lot of oil. I couldn't get her to go for the four barrel carb model.
Cute little car. Light green, two door hardtop. V-8, auto. 3.08 axle.
I added the blaster cap, lakes cap to the exhaust. I had a 4.11 Spicer rear axle out of a '51 Henry J I'd beed installing an Olds engine in. The Henry J axle mounted on the Studebaker springs okay. Pinion angle was off a little but still worked.
The thing would fly off the line with that gear.
I'd go to the drag strip on Sunday morning with the Henry axle in the trunk. Change it at the track, Race. Change back. Got where two of us could change that thing once it was up in the air in 8 minutes, brakes bled and back on the ground
When I was a Junior in high school, my mother bought a new car. She didn't know whether to buy a '60 Corvair or a '60 Studebaker Lark. I strongly encouraged her to buy the Studebaker and oh yeah Mom, while yer at it, buy the V-8 model. I've heard the six bangers use a lot of oil. I couldn't get her to go for the four barrel carb model.
Cute little car. Light green, two door hardtop. V-8, auto. 3.08 axle.
I added the blaster cap, lakes cap to the exhaust. I had a 4.11 Spicer rear axle out of a '51 Henry J I'd beed installing an Olds engine in. The Henry J axle mounted on the Studebaker springs okay. Pinion angle was off a little but still worked.
The thing would fly off the line with that gear.
I'd go to the drag strip on Sunday morning with the Henry axle in the trunk. Change it at the track, Race. Change back. Got where two of us could change that thing once it was up in the air in 8 minutes, brakes bled and back on the ground
Le Mans Master
Joined: Feb 2008
Posts: 6,482
Likes: 1,918
From: Folsom CA
Mike, your a nut. My Mom would have kicked me out for doing that in her car.
I do know the game though, when I was 13 my friends all got dirt bikes, my mother said no to dirt bikes but I could get a mini bike. So I saved my newspaper route money and got a mini bike and proceeded to put a Honda 2 cyl 160 CC engine on it with a 4 speed. It was wicked fast and more dangerous than any motorcycle on the road. But Mom was Happy.
I do know the game though, when I was 13 my friends all got dirt bikes, my mother said no to dirt bikes but I could get a mini bike. So I saved my newspaper route money and got a mini bike and proceeded to put a Honda 2 cyl 160 CC engine on it with a 4 speed. It was wicked fast and more dangerous than any motorcycle on the road. But Mom was Happy.
Race Director
Joined: Apr 2015
Posts: 17,571
Likes: 3,460
From: Fresno California
Back in 1990, my room mate had a very nice but problematic (from sitting long periods) '55 Stude President Speedster. It had the 259 Passmaster V8 with the 4bbl carb. No idea what rear screw....probably a 3.23 or 3.08. It would smoke 289 Mustangs from the dig, though. Those Studebaker V8's had a lot of bottom end torque, like the Pontiacs I drive. A lot of grunt at very low RPM. I believe the Lark, like the President, had a torque-tube type rear end.....making it no easy chore for a fast swap-out!
Le Mans Master
Joined: Oct 2000
Posts: 8,897
Likes: 1,357
From: Santa Ana CA
I had 4.11s in the '64 when I got it. Lots of fun on the street, but no fun on the freeway with 225/60/15 tires.
I had the rear end swapped out to 3.70s (different carrier and the shop was all too happy to get a 4-series carrier as they are much rarer) and they are much nicer all around.
Then I put in the Keisler TKO-600 with 0.64 OD and the 3.70s 1st gear is about like a 3.90 and works nicely.
I had the rear end swapped out to 3.70s (different carrier and the shop was all too happy to get a 4-series carrier as they are much rarer) and they are much nicer all around.
Then I put in the Keisler TKO-600 with 0.64 OD and the 3.70s 1st gear is about like a 3.90 and works nicely.
Melting Slicks
Joined: Jan 2007
Posts: 2,842
Likes: 622
From: Pasco Florida
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
Long time ago, it used to be said a couple of feet off the line was worth a car length or better at the finish line.
You're not going anywhere if you're sitting there smoking the tires.
You're not going anywhere if you're sitting there smoking the tires.
Last edited by MikeM; Mar 3, 2018 at 04:37 PM.
Pro
Joined: Dec 2017
Posts: 541
Likes: 60
From: Eustis Florida
The two-digit alphanumeric code stamped on the bottom of the diffy indicates which rear gears were installed in it at the factory.
Mine are 4.11s (correctly stated as 4.11:1). IIRC, the code is AQ.
Another way to tell you have 4.11s is the engine will spin at 3000 rpms at 60 mph with the standard sized tires.
Mine are 4.11s (correctly stated as 4.11:1). IIRC, the code is AQ.
Another way to tell you have 4.11s is the engine will spin at 3000 rpms at 60 mph with the standard sized tires.