Heating and cooling - Chevelle Tech
Heating & Cooling Heating, cooling and air conditioning Sponsored by:Cold-Case Aluminum Radiators

 13Likes
  • 3 Post By oldcutlass
  • 4 Post By hjdca
  • 1 Post By JWagner
  • 2 Post By jimbo13
  • 1 Post By Not2Fast
  • 1 Post By v8440
  • 1 Post By oldcutlass
 
LinkBack Thread Tools Search this Thread Display Modes
post #1 of 14 (permalink) Old Sep 20th, 19, 9:08 AM Thread Starter
 
Join Date: Sep 2019
Posts: 3
Heating and cooling

Hi, I have a 70 Chevelle with 454. A mechanical 19 inch 6 blade flex fan. A 4 core brass radiator which has been
rodded out and is in good condition. A 160 stat. New water pump and hoses. A add on a/c system.

I live in South Fl. It runs hot at idle and in traffic 220 to230. Out on I 95 at 60 mph it runs about 190 .
I would like to try the large 7 blade fan with fan clutch. And a aluminum radiator.
Where can I get fan and clutch ?
And recommendations for a aluminum radiator. Pros and cons.

I read about drilled thermostat . Can someone explain that. I have run car w/o thermostat and no difference in temps.
Thank you
Jim
jimbo13 is offline  
Sponsored Links
Advertisement
 
post #2 of 14 (permalink) Old Sep 20th, 19, 9:25 AM
Senior Tech Team
Eric
 
Join Date: Aug 2011
Location: Poteau, Ok
Posts: 4,210
Re: Heating and cooling

You need to read up on how a thermostat works and what its function is. It has nothing to do with your issue. You may be on the right track with the fan, clutch, and radiator. You also need to look at your ign timing and a/f mixture settings, as well as the air flow through the radiator at idle.
LeoP, Kirk's67SS and jimbo13 like this.

Your just jealous because you can't hear the voices!

1967 Olds Cutlass 468 BBC/T400
1963 Plymouth Fury 440/Torqueflite
2007 Ford Mustang GT (momma's car)
oldcutlass is offline  
post #3 of 14 (permalink) Old Sep 20th, 19, 9:47 AM
Tech Team
Harry
 
Join Date: Jan 2011
Location: Los Angeles
Posts: 303
Re: Heating and cooling

Quote:
Originally Posted by jimbo13 View Post
Hi, I have a 70 Chevelle with 454. A mechanical 19 inch 6 blade flex fan. A 4 core brass radiator which has been
rodded out and is in good condition. A 160 stat. New water pump and hoses. A add on a/c system.

I live in South Fl. It runs hot at idle and in traffic 220 to230. Out on I 95 at 60 mph it runs about 190 .
I would like to try the large 7 blade fan with fan clutch. And a aluminum radiator.
Where can I get fan and clutch ?
And recommendations for a aluminum radiator. Pros and cons.

I read about drilled thermostat . Can someone explain that. I have run car w/o thermostat and no difference in temps.
Thank you
Jim
The good fan is a 772 Chevy original air cond. fan.. You can find good used ones on ebay. Just paint it black when you get it. You can also buy by a reproduction one, they still make them. Some say the older ones are better. I have an original one that I repainted. Make sure it has curved tips. For the clutch fan, get a Hayden 2747, this is the perfect length for our cars and performs like the original GM clutch fan. You also need a reproduction shroud. That's it ! It is a piece of cake to install and if your radiator is good, you should never have cooling problems again -- even with the air cond. running in 104 degree heat. This what I run with a griffin radiator and my engine will not go past my thermostat temperature opening even in LA heat with the air cond. on. in traffic. Here is a pic of the spacing with the fan and shroud in stalled with a Griffin aluminum raditiator on my Chevelle. Shoot for this spacing. It is a proven solution. Good Luck.


Harry
1970 Chevelle SS396 (408), Fathom Blue,
Original Block & Forged Crank, KB Pistons, Edelbrock 6045 Heads,Comp Cam 292H, March Serpentine, RPM AirGap,750HP,100hp Nitrous
A/F Wideband,Tremec TKO 600, 12 bolt,
30 spline Moser Axles, Richmond 3:73's, Hotchkis control arms, swaybars, springs, Wilwood 12" rotors D/S, 4 piston calipers
hjdca is offline  
 
post #4 of 14 (permalink) Old Sep 20th, 19, 10:03 AM
Lifetime Premium Member
Bob
 
Join Date: Mar 2005
Location: Jeannette Pa. near pittsburgh
Posts: 8,425
Re: Heating and cooling

My question is: Is your cooling system in your 70 a VO-1 or a copy of the VO-1? Why I am asking . I have a (ordered by me ) a 70 LS-5//M-22 with factory A/C.
My driver is a fake SS-468, 70 Nomad Wgn. with the VO-1 cooling and FACTORY A/C. My one owner has never overheated in the 49 years I have owned it. My driver with a 468 and a 700R has never overheated.
On a very hot day my driver with the 468 and the A/C operating will get up to 205-210 sitting in bumper to bumper traffic.
It runs at 185/ 190 on the highway with the A/C operating. Normal driving town/ highway it runs always around 170--185/190.
Also on the core support, LOOK between the Rad. tanks and the core support, You will see a GAP about 5/8"-3/4" wide. When the car is static or moving slow, This large GAP will allow the SUPER HEATED air in the engine bay to be DRAWN through this GAP and back into the Rad. This will cause the water temps to go up. I filled this GAP with some foam tape with a sticky back side from LOWES.
For a stock cooling system to be effective, It MUST have ALL the factory items in place. Both of my 70s have every tidbit in place as it left the factory and I have no issues with my stock 454 or the 468.
All of the factory item work together in concert, With factory items missing ,,, YES you will have cooling issues.
Bob


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
1970 SS LS-5/M-22 El Camino- Org. Owner-AACA 2016-Senior Grand National Winner---MCACN-GOLD-2013
1970 ( FRAUD) SS 468 Station Wagon - Driver.
Robinls5 is offline  
post #5 of 14 (permalink) Old Sep 20th, 19, 2:52 PM
Senior Tech Team
Jim
 
Join Date: Oct 1999
Location: Fresno
Posts: 1,776
Re: Heating and cooling

Quote:
Originally Posted by jimbo13 View Post
Hi, I have a 70 Chevelle with 454. A mechanical 19 inch 6 blade flex fan. A 4 core brass radiator which has been
rodded out and is in good condition. A 160 stat. New water pump and hoses. A add on a/c system.

I live in South Fl. It runs hot at idle and in traffic 220 to230. Out on I 95 at 60 mph it runs about 190 .
I would like to try the large 7 blade fan with fan clutch. And a aluminum radiator.
Where can I get fan and clutch ?
And recommendations for a aluminum radiator. Pros and cons.

I read about drilled thermostat . Can someone explain that. I have run car w/o thermostat and no difference in temps.
Thank you
Jim
Runs hot at highway speed. New water pump, 160* thermostat, serviced old radiator that you say is in "good" condition. Let's assume that the water pump and thermostat are functioning as designed. Add-on AC, so the system has been modified from original GM design by a condenser in front of the radiator? Factory shroud in place and functioning correctly? Any impediments to the air flow through radiator and out of the engine bay, besides the AC condenser ?

I'd buy a new OE replacement radiator. They're cheap. You say "rodded out" and in good condition. I'd say likely not in good condition.
JJ'65 is offline  
post #6 of 14 (permalink) Old Sep 20th, 19, 7:19 PM
Gold Member
 
Join Date: Sep 1998
Location: Tucson, AZ, USA
Posts: 9,515
Re: Heating and cooling

It sounds like an air flow deficiency at idle. so improving the fan is a good idea. Lose the flex fan. Those things are trouble.
Do you have a fan shroud?
Kirk's67SS likes this.
JWagner is offline  
post #7 of 14 (permalink) Old Sep 20th, 19, 9:17 PM Thread Starter
 
Join Date: Sep 2019
Posts: 3
Re: Heating and cooling

Thanks guys. I ordered the GM 772 fan blade and the suggested fan clutch today. I'll try this before changing radiator.
I'll space fan as shown in above picture as mine is tucked inside shroud presently. The condenser is only obstruction in front of radiator.

The shroud is a 71 model duplicate and it does cover the radiator core. I'll look for a gap between support and radiator when i stick the rad back in. My thought is not to make too many changes at once.
The ignition timing is in specs through out its curve.
I'll let you all know how it goes after road test.
Thanks again
Jim
Ccass and Kirk's67SS like this.
jimbo13 is offline  
post #8 of 14 (permalink) Old Sep 20th, 19, 9:28 PM
Lifetime Premium Member
Al
 
Join Date: Apr 2011
Location: SO CAL...Huntington Beach and Rancho Cucamonga
Posts: 5,133
Garage
Re: Heating and cooling

Quote:
Originally Posted by jimbo13 View Post
Thanks guys. I ordered the GM 772 fan blade and the suggested fan clutch today. I'll try this before changing radiator.
I'll space fan as shown in above picture as mine is tucked inside shroud presently. The condenser is only obstruction in front of radiator.

The shroud is a 71 model duplicate and it does cover the radiator core. I'll look for a gap between support and radiator when i stick the rad back in. My thought is not to make too many changes at once.
The ignition timing is in specs through out its curve.
I'll let you all know how it goes after road test.
Thanks again
Jim
If you are running a 71-72 HD cooling fan shroud you should be running a 19 inch fan Part Number: 3989095. The 18 inch is not as efficient in the 71-72 shroud that was designed for a 19 inch fan.
DUTCH MAX HEADWORK is offline  
post #9 of 14 (permalink) Old Sep 20th, 19, 9:31 PM
Tech Team
 
Join Date: Sep 2015
Location: PNW
Posts: 900
Garage
Re: Heating and cooling

If the above doesn't work, and get rid of that 160 stat and drop in a 180, ditch that 4 row rad for a 2 row with some fat tubes in it. Oh yeah, more water than coolant is the way to go unless you live in a cold climate and run the car in the winter.
Kirk's67SS likes this.

'69 Malibu
Not2Fast is offline  
post #10 of 14 (permalink) Old Sep 21st, 19, 12:39 AM
Senior Tech Team
Greg.
 
Join Date: Apr 2011
Location: Ottawa, On, Canada
Posts: 4,748
Garage
Re: Heating and cooling

Quote:
Originally Posted by JJ'65 View Post
Runs hot at highway speed. New water pump, 160* thermostat, serviced old radiator that you say is in "good" condition. Let's assume that the water pump and thermostat are functioning as designed. Add-on AC, so the system has been modified from original GM design by a condenser in front of the radiator? Factory shroud in place and functioning correctly? Any impediments to the air flow through radiator and out of the engine bay, besides the AC condenser ?

I'd buy a new OE replacement radiator. They're cheap. You say "rodded out" and in good condition. I'd say likely not in good condition.
It runs 190* on the Hwy so that is okay

If he relocates the better Mech Fan at 1/2 In and 1/2 Out of the Shroud Opening
that should help too, as shown in Post # 3

And I agree with "Not To Fast " comment that a 4 Row Rad plus the A/C Condenser in front of it could be impeding the Air Flow
and thus a Alum Rad with only 2 Rows would be better for the Air Flow

67 Chevelle Malibu SS Cdn
Born 283 / PG / A51
468/TH400 2,500 stall/ S60 3.70 Gs
Prev Best on M/T ET S/S #3454 street Tires/Dress 2018/05/20
60' = 1.664
1/8 = 7.532 et / 91 mph
1/4 = 11.814 et / 115 mph
NEW Best with 3,500+ Stall TC 2019/09/08
60' = 1.547
1/8 = 7.311 et / 91.76 mph
1/4 = 11.595 et / 114.28 mph


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Kirk's67SS is offline  
post #11 of 14 (permalink) Old Sep 21st, 19, 10:24 AM
Tech Team
 
Join Date: Aug 2018
Posts: 355
Re: Heating and cooling

I wasn't sure exactly what style radiator my '71 has, and this thread just prompted me to go outside and take a look. I knew it was aluminum, but I hadn't looked closely at the inside through the cap. Sure enough, it has 2 wide rows, which is the general direction the oem's have gone in with today's increasingly cramped engine bays. I CANNOT GET THIS CAR TO OVERHEAT. No doubt the rest of the system works well for it to be this way, but consider this another vote for a modern design with 2 wide rows.
Kirk's67SS likes this.

'71 chevelle, 468, TH400, 12 bolt posi w/3.08's, drinks a lot of 87 octane.
v8440 is offline  
post #12 of 14 (permalink) Old Sep 23rd, 19, 4:04 PM
Tech Team
 
Join Date: Sep 2002
Location: USA
Posts: 905
Re: Heating and cooling

The 19.5" 7-blade fan came on other cars, like big Pontiac, olds, etc of the 70s. A wrecking yard or eBay may be a good place to look

Sent from my SM-T817V using Tapatalk

Scott
70GS455 is offline  
post #13 of 14 (permalink) Old Sep 23rd, 19, 5:24 PM
Tech Team
 
Join Date: Sep 2017
Location: South Eastern PA
Posts: 66
Re: Heating and cooling

If you haven't already, consider using this thermostat...https://www.flowkoolerwaterpumps.com...ree-thermostat
spoffie1962 is offline  
post #14 of 14 (permalink) Old Sep 23rd, 19, 5:36 PM
Senior Tech Team
Eric
 
Join Date: Aug 2011
Location: Poteau, Ok
Posts: 4,210
Re: Heating and cooling

Quote:
Originally Posted by spoffie1962 View Post
If you haven't already, consider using this thermostat...https://www.flowkoolerwaterpumps.com...ree-thermostat
This is not a thermostat problem its an airflow problem at idle.
Kirk's67SS likes this.

Your just jealous because you can't hear the voices!

1967 Olds Cutlass 468 BBC/T400
1963 Plymouth Fury 440/Torqueflite
2007 Ford Mustang GT (momma's car)
oldcutlass is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Chevelle Tech forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address. Note, you will be sent a confirmation request to this address.

Email Address:
OR

Log-in










Thread Tools Search this Thread
Show Printable Version Show Printable Version
Email this Page Email this Page
Search this Thread:

Advanced Search
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome