C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
Sponsored by:
Sponsored by:

AC problems

Thread Tools
 
Search this Thread
 
Old Aug 13, 2023 | 09:07 PM
  #1  
freddyhuerta44's Avatar
freddyhuerta44
Thread Starter
6th Gear
 
Joined: Aug 2023
Posts: 6
Likes: 0
Default AC problems

I’ve got a 77 stingray, the AC system has been updated. I have e fans on the radiator and even added a small fan on the condenser. My mechanic has the car running @225 degrees, because of the fuel injection system on the car. The high side pressure gets up to 400. He put a switch to manually turn on the fans, which helps, but I’m still not comfortable. Should I turn the temp sensor down? Or is there something else I can do to make this system work better? Thank you in advance
Reply
Old Aug 13, 2023 | 09:37 PM
  #2  
calwldlife's Avatar
calwldlife
Team Owner
15 Year Member
Loved
Community Favorite
Top Answer: 1
 
Joined: Jan 2007
Posts: 53,648
Likes: 878
From: Southern Cal Ca
St. Jude Donor '22
Default

are we talking 134a refrig?
400 on high side?
what is low side and weather temp?
Reply
Old Aug 13, 2023 | 09:40 PM
  #3  
freddyhuerta44's Avatar
freddyhuerta44
Thread Starter
6th Gear
 
Joined: Aug 2023
Posts: 6
Likes: 0
Default

Yes sir 134, the low side I believe is @40 and the temp over here is @100 right now. It’s pretty warm
Reply
Old Aug 13, 2023 | 09:46 PM
  #4  
calwldlife's Avatar
calwldlife
Team Owner
15 Year Member
Loved
Community Favorite
Top Answer: 1
 
Joined: Jan 2007
Posts: 53,648
Likes: 878
From: Southern Cal Ca
St. Jude Donor '22
Default

Originally Posted by freddyhuerta44
Yes sir 134, the low side I believe is @40 and the temp over here is @100 right now. It’s pretty warm
numbers are
50-55 low side
315-325 high side.
@ 100 deg weather

your high s is too much
low s not enough

curious
did you change the expansion/spray system?

Reply
Old Aug 14, 2023 | 12:52 AM
  #5  
bruiser's Avatar
bruiser
Melting Slicks
15 Year Member
Active Streak: 30 Days
Active Streak: 60 Days
Active Streak: 120 Days
 
Joined: Feb 2007
Posts: 2,709
Likes: 269
From: S.E. MI
St. Jude Donor '15
Default

I think my high pressure is around 250. I use a blue Ford orifice tube.
Reply
Old Aug 14, 2023 | 04:04 AM
  #6  
freddyhuerta44's Avatar
freddyhuerta44
Thread Starter
6th Gear
 
Joined: Aug 2023
Posts: 6
Likes: 0
Default

My low is @50 at idle but the high is what I’m trying to get down.
Reply
Old Aug 14, 2023 | 04:05 AM
  #7  
freddyhuerta44's Avatar
freddyhuerta44
Thread Starter
6th Gear
 
Joined: Aug 2023
Posts: 6
Likes: 0
Default

I’m gonna ask the mechanic about that cord oriface tube
Reply
Old Aug 14, 2023 | 04:07 AM
  #8  
freddyhuerta44's Avatar
freddyhuerta44
Thread Starter
6th Gear
 
Joined: Aug 2023
Posts: 6
Likes: 0
Default

On the expansion and spray system I’m not aware. I know he changed the dryer compressor and o rings.
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

10 Ugly Corvettes That We Still Kinda Love

 Joe Kucinski
story-1

Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

 Brett Foote
story-2

10 Things Every Corvette Owner Needs (2026 Edition)

 Michael S. Palmer
story-3

8 Most "Only Corvette Owners Understand" Quirks and Problems

 Pouria Savadkouei
story-4

10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

 Joe Kucinski
story-5

How Much Horsepower Every Corvette Engine "LOST" in 1972

 Joe Kucinski
story-6

Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

 Michael S. Palmer
story-7

Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

 Joe Kucinski
story-8

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-9

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
Old Aug 14, 2023 | 06:22 AM
  #9  
TommyFox's Avatar
TommyFox
Melting Slicks
10 Year Member
Photogenic
Photoriffic
Liked
 
Joined: Jun 2011
Posts: 2,383
Likes: 385
From: Leland , North Carolina
Default

The condenser for R-12 performs poorly when switching over to 134. It's been a long time since I converted one but done a few back in the day.. Contemplating what I'm going to do on my 80. I do remember changing the condenser on a few of these cars and getting 38* or so out of the the vent vs about 48* with original condeser from what I recall.

Reply
Old Aug 14, 2023 | 07:47 AM
  #10  
4-vettes's Avatar
4-vettes
Race Director
15 Year Member
Liked
Loved
Top Answer: 1
 
Joined: Nov 2006
Posts: 13,229
Likes: 7,825
From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
2024 C3 of the Year Finalist- Modified
2022 C3 of the Year Finalist - Modified
Cruise-In VIII Veteran
Default

I have a 77 , also upgraded air-con. With a trienary switch to kick on my electric fans when pressure rises. Pretty much only happens when not moving. I run a parallel flow condenser, and with fuel injection there is absolutely no reason to be running your engine that bloody Hot!
with EFI it should run perfectly at 160 degrees although this wouldn't be the best for reducing condensation from the engine. Most of us run a 180 thermostat. My EFI 77 runs right on 190, 90 percent of the time. My twin electric fans kick on at 195 and I can watch the temp drop on the guage. Slowly, but it goes down. Then the fans shut down. No fan in front of the condenser. Shouldn't need one with proper fans behind the rad.
trienary switch is a much, much better set-up than a manual switch.
I ran a thread on here a couple years ago. "73-E77 air-con upgrade ". Do a Google search on it. Filled with information.
But ask WHY do you need your engine running so hot. Never heard such nonsense.
I live in Tropical Queensland, Australia. I know hot weather.
Reply
Old Aug 14, 2023 | 05:31 PM
  #11  
freddyhuerta44's Avatar
freddyhuerta44
Thread Starter
6th Gear
 
Joined: Aug 2023
Posts: 6
Likes: 0
Default

Thank you very much, I agree on the engine temperature. However the mechanic swears by it. Like if I had an aluminum block LS or something. Mine is a 3rd gen 350 with an edelbrock efi. Gonna turn down that temperature and ask him about that condenser. Didn’t think of that on. Thank you all for the great advice.
Reply
Old Aug 14, 2023 | 10:14 PM
  #12  
4-vettes's Avatar
4-vettes
Race Director
15 Year Member
Liked
Loved
Top Answer: 1
 
Joined: Nov 2006
Posts: 13,229
Likes: 7,825
From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
2024 C3 of the Year Finalist- Modified
2022 C3 of the Year Finalist - Modified
Cruise-In VIII Veteran
Default

Perhaps that mechanic swears by running your engine right on the edge. But most would not.
just like going to a doctor, sometimes its a good idea to get a second opinion.
Reply
Old Aug 16, 2023 | 01:19 PM
  #13  
wwiiavfan's Avatar
wwiiavfan
Drifting
Liked
Loved
Community Favorite
Top Answer: 1
 
Joined: Oct 2020
Posts: 1,567
Likes: 576
From: Wisconsin
Default

Ask if your mechanic will cover the cost of rebuilding your motor if it overheats and see if he still recommends the same running temp. 😀
Reply

Get notified of new replies

To AC problems





All times are GMT -4. The time now is 01:54 PM.

story-0
10 Ugly Corvettes That We Still Kinda Love

Slideshow: 10 ugly Corvettes that we still kinda love.

By Joe Kucinski | 2026-06-03 10:34:17


VIEW MORE
story-1
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

A lot of money has changed hands at the online auction house over the years.

By Brett Foote | 2026-06-03 10:21:50


VIEW MORE
story-2
10 Things Every Corvette Owner Needs (2026 Edition)

Slideshow: 10 great gifts Corvette enthusiasts actually want for Father's Day!

By Michael S. Palmer | 2026-06-03 15:43:40


VIEW MORE
story-3
8 Most "Only Corvette Owners Understand" Quirks and Problems

Slideshow: These are the quirks, annoyances, and oddly lovable problems that every Corvette owner eventually learns to live with.

By Pouria Savadkouei | 2026-05-28 09:31:39


VIEW MORE
story-4
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

Slideshow: 10 reasons why the C6 Z06 is still a performance benchmark after 20 years.

By Joe Kucinski | 2026-05-27 17:20:09


VIEW MORE
story-5
How Much Horsepower Every Corvette Engine "LOST" in 1972

Slideshow: How much horsepower every Corvette engine lost in 1972.

By Joe Kucinski | 2026-05-27 16:54:53


VIEW MORE
story-6
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE
story-7
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

Slideshow: The 10 most explosive Corvettes ever built based on power-to-weight ratio.

By Joe Kucinski | 2026-05-20 07:23:03


VIEW MORE
story-8
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-9
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE