Why so many C2 cooling problems?
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
Drifting
Joined: Jun 2005
Posts: 1,974
Likes: 2
From: Crownsville Md.
Shemp
Race Director
Joined: Mar 2002
Posts: 13,637
Likes: 3,583
From: NorCal
I've never had an overheating Sting Ray and I've owned 21 of them, including in SoCal where the summers were plenty hot. Keep it all stock and you'll have no overheating problems. The '67 327 I've had for the past 10 years has a bit more HP than stock and never overheats, including during summer autocrosses with the A/C on! If the stock radiator ever gives up the ghost I'll get a DeWitt's replacement.
Race Director
Joined: Oct 2000
Posts: 15,036
Likes: 79
From: central FL, near the beach.
3 years ago i put a radiator made for a 4 cyl VW in my 61. it weighs 4.5#, holds only 40 OUNCES. never overheats, but does cruise at 190F vs 180.
I was inspired by all the guys here that have problems. I wanted to see how small it could be on a car that runs right. It cost $125 and i overpaid. Now i see them for $80
Got rid of the old fan/shroud.
Added undersize elec. fans that only draw 8A total. I use them only in slow/stopped traffic.
I was inspired by all the guys here that have problems. I wanted to see how small it could be on a car that runs right. It cost $125 and i overpaid. Now i see them for $80
Got rid of the old fan/shroud.
Added undersize elec. fans that only draw 8A total. I use them only in slow/stopped traffic.
Last edited by Matt Gruber; Oct 7, 2012 at 02:39 PM.
Team Owner
Joined: Oct 2000
Posts: 38,897
Likes: 1,926
From: Washington Michigan
3 years ago i put a radiator made for a 4 cyl VW in my 61. it weighs 4.5#, holds only 40 OUNCES. never overheats, but does cruise at 190F vs 180.
I was inspired by all the guys here that have problems. I wanted to see how small it could be on a car that runs right. It cost $125 and i overpaid. Now i see them for $80
Got rid of the old fan/shroud.
Added undersize elec. fans that only draw 8A total. I use them only in slow/stopped traffic.
I was inspired by all the guys here that have problems. I wanted to see how small it could be on a car that runs right. It cost $125 and i overpaid. Now i see them for $80
Got rid of the old fan/shroud.
Added undersize elec. fans that only draw 8A total. I use them only in slow/stopped traffic.
Race Director
Joined: Oct 2000
Posts: 15,036
Likes: 79
From: central FL, near the beach.
i put only one, 1 gal tank in my 67 
in my 61, when i stop for gas i get 3.5 gallons usually. in my 72 i get 3-5 gallons and my 72 has an 18 gal tank. Never gets past 3/8 tank.
After 5 years, i'm pleased with the gas capacity in my 61. I could up it to 7 gal in 5 min., but i've never needed more gas so i stick with 4. It never gets stale. And it never runs out of gas. It gets 14.5-18 mpg around town. Very hard to run out of gas when i know exactly how much is in there. I've never even had to switch from tank 1 to tank 2 during a trip. I do have a normal tank if i get a job in NJ and have to commute
in my 61, when i stop for gas i get 3.5 gallons usually. in my 72 i get 3-5 gallons and my 72 has an 18 gal tank. Never gets past 3/8 tank.
After 5 years, i'm pleased with the gas capacity in my 61. I could up it to 7 gal in 5 min., but i've never needed more gas so i stick with 4. It never gets stale. And it never runs out of gas. It gets 14.5-18 mpg around town. Very hard to run out of gas when i know exactly how much is in there. I've never even had to switch from tank 1 to tank 2 during a trip. I do have a normal tank if i get a job in NJ and have to commute
Last edited by Matt Gruber; Oct 7, 2012 at 03:36 PM.
Drifting
Joined: Jun 2005
Posts: 1,974
Likes: 2
From: Crownsville Md.
I've never had an overheating Sting Ray and I've owned 21 of them, including in SoCal where the summers were plenty hot. Keep it all stock and you'll have no overheating problems. The '67 327 I've had for the past 10 years has a bit more HP than stock and never overheats, including during summer autocrosses with the A/C on! If the stock radiator ever gives up the ghost I'll get a DeWitt's replacement.
Just sayin Shemp
Former Vendor
Joined: Jan 2000
Posts: 5,593
Likes: 631
From: Brighton
If you do not see this change when re-connecting the vacuum line, the diaphragm in the can is probably broken, if you see a small change it could be a ported (metered) vacuum connection.
To prove to yourself this vacuum can malfunction can cause idle over heating, just loosen the distributor and turn the timing up to about 22 degrees but don't drive the car this way. You will notice it will run cooler for much longer. Nine out of ten (90%) of the cases if idle overheating are related to timing issues. See John Z article on cooling issues for a detailed report on this subject.
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
Le Mans Master
Joined: Dec 2007
Posts: 8,000
Likes: 659
From: Puget Sound
A buddy called me about an overheating issue with his 1959 270HP 283 that couldn't be solved. It would idle all day long and not over heat but as soon as you started driving, it got too hot. The local "expert" flushed the motor, new water pump, new thermostat, new hoses and it still got hot. He was then talked into a new radiator and it still got hot. Now he's into this several thousand dollars and still has a problem. I told him "It's in your distributor. The weights are probably rusted/stuck. Pop the cap and make sure they're free." 10 mins. and $0 later, the problem was fixed. The moral of the moral of the story, make sure the stuff you have is working correctly.
Jim
Race Director
Joined: Mar 2002
Posts: 13,637
Likes: 3,583
From: NorCal
My comment might have sounded too smug, sorry. I sometimes did buy a Sting Ray that had overheating problems, then I put everything back to stock, but it still overheated. It turns out that one of the stock parts wasn't functioning properly. The posting by 1snake is a perfect example of a stock distributor not functioning right so making the car overheat. For your car it's time to check out the not-very-likely causes for overheating. Have you made sure the timing is spot on, and that the distributor parts are all the right ones and working right?
Le Mans Master
Joined: Oct 2000
Posts: 5,224
Likes: 879
From: PERCUSSIVE MAINTENANCE: The art of whacking the crap out of an electronic device to get it to work.
My 67 427 will overheat at idle if the vacuum can is connected to the stock ported vacuum source. When it's connected to manifold vacuum, no overheating.
Le Mans Master
Joined: Mar 2010
Posts: 6,501
Likes: 1,938
From: The Golden Triangle, Florida
2024 C2 of the Year Finalist - Unmodified
2023 C2 of the Year Finalist - Unmodified
St. Jude Donor '20 thru '25
If original cars didn't overheat back in the day and the same cars with stock configurations are overheating now, I think Al Gore should use that as additional proof of global warming 
.
-- Steve
.-- Steve
Race Director
Joined: Aug 2004
Posts: 15,304
Likes: 2,263
From: NorCal
Race Director
Joined: Oct 2000
Posts: 15,036
Likes: 79
From: central FL, near the beach.
Idle speed too high burns more gas, makes more heat for the rad. to remove.
When my 61 idle was 800-900 it used 2 GPH of fuel. at 625 it uses 0.9 GPH. At that time i switched to a 4 hole carb base gasket from open center. Idle mix screws were 3 turns out w/open center, now 1.5 w/4 hole gasket.
When my 61 idle was 800-900 it used 2 GPH of fuel. at 625 it uses 0.9 GPH. At that time i switched to a 4 hole carb base gasket from open center. Idle mix screws were 3 turns out w/open center, now 1.5 w/4 hole gasket.