i just dont know lol i guess when i change the gear oil il check the gears will update when done
gear ratio?
Thread Starter
Racer
Joined: Jul 2009
Posts: 344
Likes: 5
From: oak harbor wa
gear ratio?
well hello all corvette owners and lovers im a recently new corvette owner.....
77 Corvette
Here is my issue im pretty good with cars even for being so young some say i know alot of the old schhol tricks but im in a pickle of being lazy i dont want to pull axle cover off to count teeth... well i believe that i have 3.89 in the *** end but all other people say no way so heres what i have tried the tire size is 245 45 17... at 50 mph its sitting at 3100-3200 rpm and the speed is checked that with wife next to me... also used the jacking the car up mark driveline and tire and what i get is 3 and a lil more than 3/4 full turns on driveline and 1 full tire turn marked tire also so my thinking is 3.89 but what yall think
77 Corvette
Here is my issue im pretty good with cars even for being so young some say i know alot of the old schhol tricks but im in a pickle of being lazy i dont want to pull axle cover off to count teeth... well i believe that i have 3.89 in the *** end but all other people say no way so heres what i have tried the tire size is 245 45 17... at 50 mph its sitting at 3100-3200 rpm and the speed is checked that with wife next to me... also used the jacking the car up mark driveline and tire and what i get is 3 and a lil more than 3/4 full turns on driveline and 1 full tire turn marked tire also so my thinking is 3.89 but what yall think
Pro
Joined: Mar 2009
Posts: 703
Likes: 2
From what I just looked up, your tires are 25.7" tall.. Thats alot of RPM's for 50mph.. What trans do you have? If your turning over 3100 rpm with a th350 or th400 with a final drive gear of 1.1, your talking a gear that is higher than 4.11 My 4.56 in my Camaro didnt even turn that many RPM's at 50..
Thread Starter
Racer
Joined: Jul 2009
Posts: 344
Likes: 5
From: oak harbor wa
new tach and heres what i got
rpm at 3000 rpms, speed at 50mph dead on, i ran this quick check
rpms===3000
speed====50mph
tire size 245/45/17, Tire Diameter (Height) in Inches 25.68
trans th350
makes gears 4.59 approx.
what do you guys think now??
rpms===3000
speed====50mph
tire size 245/45/17, Tire Diameter (Height) in Inches 25.68
trans th350
makes gears 4.59 approx.
what do you guys think now??
Last edited by lowes-yellow77; Apr 11, 2012 at 09:40 PM. Reason: forgot tranny type
Le Mans Master
Joined: Mar 2008
Posts: 5,948
Likes: 72
From: Oxford MA-----You just lost the game!!!!
1977 Corvette Axle Ratios
Code Ratio
OA 3.08
OD 3.36
LR 3.36
OB 3.55
OC 3.70
Got the above list off this site:
http://corvettec3.ca/axle.htm
That doesn't mean you don't have some aftermarket gears in there, though. But I would have to go along with Gordonm and say 3.70.
Keep the shiny side up!
Scott
Code Ratio
OA 3.08
OD 3.36
LR 3.36
OB 3.55
OC 3.70
Got the above list off this site:
http://corvettec3.ca/axle.htm
That doesn't mean you don't have some aftermarket gears in there, though. But I would have to go along with Gordonm and say 3.70.
Keep the shiny side up!
Scott
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Thread Starter
Racer
Joined: Jul 2009
Posts: 344
Likes: 5
From: oak harbor wa
aftermarket
im sure it has to aftermarket gears because the stamp on axle calls for 3.08`s well its a hell of a thrill up to about 70 or so with a nicely built 350 pushing around 300hp(est) to the wheels, i guess the main reason i started all of this for the hopes to swap in a 4 or 5 speed one day,
the only reason i bought a auto vs standard was at the time around here all the 4 speed cars needed to much body work and were the same price.
also there is a guy on good ol craigslist said he would sell everything for 4 speed swap from a 77 for 1200 bucks, this will include pedals,tranny, flywheel,clutch,all linkgage, all he knows is that it worked before he started parting car out mileage unknown shoulda i give it a go or just keep my th350 with less than 2000 miles with stage 2 kit
the only reason i bought a auto vs standard was at the time around here all the 4 speed cars needed to much body work and were the same price.
also there is a guy on good ol craigslist said he would sell everything for 4 speed swap from a 77 for 1200 bucks, this will include pedals,tranny, flywheel,clutch,all linkgage, all he knows is that it worked before he started parting car out mileage unknown shoulda i give it a go or just keep my th350 with less than 2000 miles with stage 2 kit
Safety Car
Joined: Nov 2008
Posts: 3,713
Likes: 550
From: Seattle Washington
im sure it has to aftermarket gears because the stamp on axle calls for 3.08`s well its a hell of a thrill up to about 70 or so with a nicely built 350 pushing around 300hp(est) to the wheels, i guess the main reason i started all of this for the hopes to swap in a 4 or 5 speed one day,
the only reason i bought a auto vs standard was at the time around here all the 4 speed cars needed to much body work and were the same price.
also there is a guy on good ol craigslist said he would sell everything for 4 speed swap from a 77 for 1200 bucks, this will include pedals,tranny, flywheel,clutch,all linkgage, all he knows is that it worked before he started parting car out mileage unknown shoulda i give it a go or just keep my th350 with less than 2000 miles with stage 2 kit
the only reason i bought a auto vs standard was at the time around here all the 4 speed cars needed to much body work and were the same price.
also there is a guy on good ol craigslist said he would sell everything for 4 speed swap from a 77 for 1200 bucks, this will include pedals,tranny, flywheel,clutch,all linkgage, all he knows is that it worked before he started parting car out mileage unknown shoulda i give it a go or just keep my th350 with less than 2000 miles with stage 2 kit
Burning Brakes
Joined: Dec 2003
Posts: 1,004
Likes: 7
From: Adelaide South Australia
A 77 vette with 300hp at the wheels with a 350 cube motor and an auto trans would equate to 400 flywheel horsepower. That's pretty healthy and would probably need low diff gears and/or high stall converter to get going strong from launch.
What stall speed converter do you have?
Maybe the high rpm at 50mph is simply converter slippage?
What stall speed converter do you have?
Maybe the high rpm at 50mph is simply converter slippage?
Thread Starter
Racer
Joined: Jul 2009
Posts: 344
Likes: 5
From: oak harbor wa
stall
if i brake it and gas it ie stall test, the car will begin to lurch around 1500-1800 rpm which is about normal for a turbo 350 as far as i know, i also highly doubt i have a stall coverter because sitting at a stop light gets annoying sometimes with the jerky feeling while sitting still @gale banks is this the same guy in winlock,wa?
Burning Brakes
Joined: Apr 2007
Posts: 1,039
Likes: 62
From: Kona Hawaii
Went thru a TH350 to Richmond 6spd swap last August.http://forums.corvetteforum.com/c3-t...am-change.html
It's a lot of work but well worth it! I wouldn't do it for just a 4 spd.Driving with the OD is so much smoother on the highway.You need to match your trans to the rear gears.Look to get that take off ratio close to 10:1 example my first gear is 3.27 and my rear gears are 3.08 for a 10.07 great for launches.You'll have to know your rear gears to decide which trans to go with...Aloha's
It's a lot of work but well worth it! I wouldn't do it for just a 4 spd.Driving with the OD is so much smoother on the highway.You need to match your trans to the rear gears.Look to get that take off ratio close to 10:1 example my first gear is 3.27 and my rear gears are 3.08 for a 10.07 great for launches.You'll have to know your rear gears to decide which trans to go with...Aloha's