Radiator cap pressure
Thread Starter
Pro
Joined: Aug 2006
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From: COOKEVILLE TN
Radiator cap pressure
What pressure cap should I run on a '73 350/400TH, A/C not hooked up. The guy at the Radiator Shop told me to run a 7lbs cap & the radiator would last a lot longer.
Terry
Terry
Race Director
Joined: May 2006
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seems like a bad idea, the coolant will start boiling at a much lower temperature. The normal cap is 15 pounds. If you have weak radiator you fix it or replace it, you dont place a lower pressure cap on it.
Team Owner
Joined: Jan 2006
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From: Crossville TN
Cross that "mechanic" off your list of credible sources of information. Put the correct cap on the radiator. The C3 cooling system is "adequate", so putting a cap on there that would allow it to boil over sooner, is not a good idea.
Thread Starter
Pro
Joined: Aug 2006
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From: COOKEVILLE TN
I'm running a 13lb cap right now without any overheating problems. I just had leak in a 39 year old radiator. The guy was trying to save me the price of a new one or recore this one for around $400.
Race Director
Joined: May 2006
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the price for a new one is $380 plus labor why recore? Plus you can use the correct cap.
http://willcoxcorvette.com/product_i...ducts_id=24273
http://willcoxcorvette.com/product_i...ducts_id=24273
Race Director
Joined: Apr 2003
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From: Tampa, Florida
Recore at $400? Does that include R&R? I think paid less than $200 to have mine done but then again I did the R&R.
And the mechanic was right...a lower pressure capwill make your radiator last longer...you might over heat sooner but your less likely to blow out the radiator.
And the mechanic was right...a lower pressure capwill make your radiator last longer...you might over heat sooner but your less likely to blow out the radiator.
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Michael S. Palmer
Team Owner
Joined: Aug 1999
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From: Ontario
Recore at $400? Does that include R&R? I think paid less than $200 to have mine done but then again I did the R&R.
And the mechanic was right...a lower pressure capwill make your radiator last longer...you might over heat sooner but your less likely to blow out the radiator.
And the mechanic was right...a lower pressure capwill make your radiator last longer...you might over heat sooner but your less likely to blow out the radiator.
Drifting
Joined: Jul 2006
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From: Sloatsburg NY
Oldtimer
Looks like sooner or hopefully later you'll have to spring for a new radiator.
Thread Starter
Pro
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From: COOKEVILLE TN
Racer
Joined: Apr 2012
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From: Austell Georgia
If my math is any good with a 7lb cap and a 50/50 mix the boiling point is around 240 as opposed to 265 with the 15lb cap. Don't see a major problem to get by until it's time for the new radiator
Drifting
Joined: Aug 2005
Posts: 1,372
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From: Springfield VA
You can get a aftermarket Rad at eBay for less than $180 shipped. Unless yours is a number matching show car $400 is to much for a recore.
And yes run the 15psi, its what our cars were made to run.
And yes run the 15psi, its what our cars were made to run.