Not just another "cooling" thread
Thread Starter
Melting Slicks
Joined: Oct 2002
Posts: 3,193
Likes: 1
From: Cincinnati Oh
Not just another "cooling" thread
The radiator is OEM replacement aluminum, clean, 2 yrs old. Brand new edelbrock "high flow" pump with operating main fan which is also less than 2 yrs old. Just replaced coolant, near a 70-80% mix for Ohio seasons.
Car likes to get hot at idle. When moving it will stay at or below ~200* F. But idling it will creep over 240* and up (ambient temps 85-95* F)! I'm running a superram'd 383, LPE 219 cam with 19* advance at idle and appropriate fuel mixutures per the ECM and no glowing exhaust manifolds. No A/C or condenser in the way, outside of the radiator I just have a stand-alone tranny cooler.
So, have I maxed out the cooling efficiency of the OEM radiator and fan assembly? 84's only have one main fan and it runs 100% of the time when under 20 miles an hour or so and I have yet to see it plateau on idle coolant temps... I have to shut it down at 240*-ish for my own sake.
Outside of adjusting the coolant mixure to more water than antifreeze, should I justify to myself a bigger aluminum aftermarket radiator and/or a high-end CFM fan? I have yet to see a ballpark on the CFM of the stock fans in the archives, so I don't know what ballpart I need to shoot for.
Advice?
Car likes to get hot at idle. When moving it will stay at or below ~200* F. But idling it will creep over 240* and up (ambient temps 85-95* F)! I'm running a superram'd 383, LPE 219 cam with 19* advance at idle and appropriate fuel mixutures per the ECM and no glowing exhaust manifolds. No A/C or condenser in the way, outside of the radiator I just have a stand-alone tranny cooler.
So, have I maxed out the cooling efficiency of the OEM radiator and fan assembly? 84's only have one main fan and it runs 100% of the time when under 20 miles an hour or so and I have yet to see it plateau on idle coolant temps... I have to shut it down at 240*-ish for my own sake.
Outside of adjusting the coolant mixure to more water than antifreeze, should I justify to myself a bigger aluminum aftermarket radiator and/or a high-end CFM fan? I have yet to see a ballpark on the CFM of the stock fans in the archives, so I don't know what ballpart I need to shoot for.
Advice?
Race Director
Joined: Sep 2000
Posts: 17,298
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From: The Top of Utah
Originally Posted by Ramanstud
Just replaced coolant, near a 70-80% mix for Ohio seasons.
RACE ON!!!
Thread Starter
Melting Slicks
Joined: Oct 2002
Posts: 3,193
Likes: 1
From: Cincinnati Oh
Yeah the radiator is clean and the ousides cleaned of debri... 
I've searched the archives enough to pick up on that one and on the ideal mix of antifreeze. the two variables I'm unsure of are:
How big of a temp difference 50/50 versus 30/70 would make, and what CFM the oem fans can pull. So although I'll adjust the coolant mix for more heat disappation, I would think that a motor should be able to idle without burning itself up! haha.
Anybody with a SR / 219 cam have heat issues with OEM cooling components?
I've searched the archives enough to pick up on that one and on the ideal mix of antifreeze. the two variables I'm unsure of are:
How big of a temp difference 50/50 versus 30/70 would make, and what CFM the oem fans can pull. So although I'll adjust the coolant mix for more heat disappation, I would think that a motor should be able to idle without burning itself up! haha.
Anybody with a SR / 219 cam have heat issues with OEM cooling components?
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by Ramanstud
How big of a temp difference 50/50 versus 30/70 would make, and what CFM the oem fans can pull.
I agree the engine ought to be able to sit and idle. Is your fuel mixture lean? Timing retarded? Sorry, I have never seen a cfm rating on the stock fans.
RACE ON!!!
Racer
Joined: Apr 2003
Posts: 426
Likes: 0
From: Detroit MI
What shape is the a/c condensor in ?
Mine had a bunch of bent/closed fin areas that prevented the air to get to the radiator.
AC worked fine but it ran hot.
My bad missed that the condensor was out.
Mine had a bunch of bent/closed fin areas that prevented the air to get to the radiator.
AC worked fine but it ran hot.
My bad missed that the condensor was out.
Last edited by -js-; Jun 26, 2005 at 12:03 PM.
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Read the beginning of his post. He doesn't have an a/c condenser, only the radiator.
From cold, open the radiator cap and let it idle until you get to the opening temp of the thermostat. Then you will be able to see if you have reasonable coolant flow. Low flow, low ability to cool your engine. I have a stock 87 except for a Stewart water pump and at idle in the summer, the coolant goes to 200 F (195 stat) and quickly cools down to 195-198 when I get underway (50% antifreeze). Your cam could be causing more heat at idle and I recommend 50% or lower antifreeze and if the above test shows low coolant flow, up the idle speed.
From cold, open the radiator cap and let it idle until you get to the opening temp of the thermostat. Then you will be able to see if you have reasonable coolant flow. Low flow, low ability to cool your engine. I have a stock 87 except for a Stewart water pump and at idle in the summer, the coolant goes to 200 F (195 stat) and quickly cools down to 195-198 when I get underway (50% antifreeze). Your cam could be causing more heat at idle and I recommend 50% or lower antifreeze and if the above test shows low coolant flow, up the idle speed.
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Thread Starter
Melting Slicks
Joined: Oct 2002
Posts: 3,193
Likes: 1
From: Cincinnati Oh
a couple of details:
I'm using an aftermarket fan relay that causes the single fan to come on around 210* F from the cylinder head sensor. As previously stated, no A/C condendsor and since I removed the engine to do the cam install and other things, the rad was removed, cleaned and debri removed from the shroud.
I did dilute the coolant some yesterday but I have yet to check the actual mixture ratio so the word is still out on that. Also, I'm uing a 180* T-stat that appears to be functioning properly. THe engine drives well and seems to be running properly at idle via Datamaster scans - the O2 voltage is on target with total timing in the 19* range.
I'll check the T-stat operating range to verify an increase in coolant flow at the opening temp - but given the engine's ability to cool while moving and essentially all other conditions other than idle it doesn't make sense that the thermo would be stuck closed or signifigantly reduce cooling power. I think at this point my main problems are either going to be the coolant mixture or maxing out of the stock fan at idle.
I'll post what I find...
I'm using an aftermarket fan relay that causes the single fan to come on around 210* F from the cylinder head sensor. As previously stated, no A/C condendsor and since I removed the engine to do the cam install and other things, the rad was removed, cleaned and debri removed from the shroud.
I did dilute the coolant some yesterday but I have yet to check the actual mixture ratio so the word is still out on that. Also, I'm uing a 180* T-stat that appears to be functioning properly. THe engine drives well and seems to be running properly at idle via Datamaster scans - the O2 voltage is on target with total timing in the 19* range.
I'll check the T-stat operating range to verify an increase in coolant flow at the opening temp - but given the engine's ability to cool while moving and essentially all other conditions other than idle it doesn't make sense that the thermo would be stuck closed or signifigantly reduce cooling power. I think at this point my main problems are either going to be the coolant mixture or maxing out of the stock fan at idle.
I'll post what I find...
Race Director
Joined: Sep 2000
Posts: 17,298
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From: The Top of Utah
I think the water/antifreeze concentration can make a little difference, but I expect it will be subtle, at best. I think the best clue is in this quote.
Nineteen degrees, total timing is a good 15*, if not more, retarded from the ideal total required to make power. And that is ASSUMING you mean total in the sense of the old time max advance (all mechanical) at WOT. If that was a steady state observation made with a scanner, then it is even worse, because the 19* observed ,would include what would be considered vacuum advance with a mechanical distributor. If you wrote it correctly, and I understand it correctly, I think you have serious timing issues.
RACE ON!!!
Originally Posted by Ramanstud
THe engine drives well and seems to be running properly at idle via Datamaster scans - the O2 voltage is on target with total timing in the 19* range.
RACE ON!!!
Thread Starter
Melting Slicks
Joined: Oct 2002
Posts: 3,193
Likes: 1
From: Cincinnati Oh
Originally Posted by CFI-EFI
Nineteen degrees, total timing is a good 15*, if not more, retarded from the ideal total required to make power. And that is ASSUMING you mean total in the sense of the old time max advance (all mechanical) at WOT. If that was a steady state observation made with a scanner, then it is even worse, because the 19* observed ,would include what would be considered vacuum advance with a mechanical distributor. If you wrote it correctly, and I understand it correctly, I think you have serious timing issues.
RACE ON!!!
RACE ON!!!
Are you running a drastically different advance at idle or did you think I was saying the total timing the engine ever sees under any circumstance is 19* advanced?
Race Director
Joined: Sep 2000
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From: The Top of Utah
Originally Posted by Ramanstud
did you think I was saying the total timing the engine ever sees under any circumstance is 19* advanced?
RACE ON!!!
Thread Starter
Melting Slicks
Joined: Oct 2002
Posts: 3,193
Likes: 1
From: Cincinnati Oh
sorry! I meant "total timing AT idle was 19*"
However, I pulled the exhaust today to drop the transmission and I noticed the driver's side of the front Y pipe was chalky white (no "power" or deposits, but paper-white in color on the inside). the passenger's had what I equate to a normal opaque color. SO I may be getting coolant into one of the combustion chambers of #1-7. that may be causing extra heat if it goes both ways, although the coolant itself looks clear green with no bubbles or foam...
Oh well, another lead to chase down.
However, I pulled the exhaust today to drop the transmission and I noticed the driver's side of the front Y pipe was chalky white (no "power" or deposits, but paper-white in color on the inside). the passenger's had what I equate to a normal opaque color. SO I may be getting coolant into one of the combustion chambers of #1-7. that may be causing extra heat if it goes both ways, although the coolant itself looks clear green with no bubbles or foam...
Oh well, another lead to chase down.
Last edited by Ramanstud; Jun 26, 2005 at 09:17 PM.
Safety Car
Joined: Dec 2002
Posts: 3,655
Likes: 24
From: Charleston SC
The only help I can offer here is the 84 fan wouldn't cut it for the LT1 after I converted the car. I know it is not the same thing but perhaps it will give you some idea of a posible limitation of the fan. I installed a 95 Z28 duel fan assy and it cooled perfect after that. It did require hacking up the stock shroud but it solved my cooling problems for a lot less money then a custom alm. radiator.
Thread Starter
Melting Slicks
Joined: Oct 2002
Posts: 3,193
Likes: 1
From: Cincinnati Oh
thanks for the above post. There's virtually no information on CFM per HP requirements in the archives - so your post helps me think that the OEM 84 fan may not (even in it's prime) be able to effectively deal with the heat from a modded stroker motor relative to the output from the stock crossfire....
Can you email me a pic of the mods you did to your fan shroud, and the part # of your fan?
Can you email me a pic of the mods you did to your fan shroud, and the part # of your fan?
Safety Car
Joined: Dec 2002
Posts: 3,655
Likes: 24
From: Charleston SC
Send me your e-mail address to ejfagal@yahoo.com and i will send the only to pics I have left of it mouted. The 84 reached a tragic end about two uears ago.
Here she is at her best
Somthing I would rather forget
Here she is at her best
Somthing I would rather forget
Thread Starter
Melting Slicks
Joined: Oct 2002
Posts: 3,193
Likes: 1
From: Cincinnati Oh
I saw that on your webpage (linked from sig). At least you're around to drive another one.... Oh, and your email address bounced - so feel free to email me at jesjhami@indiana.edu
Last edited by Ramanstud; Jun 27, 2005 at 02:23 AM.