DeWitts Question - auto or manual
Thread Starter
Burning Brakes
Joined: Apr 2007
Posts: 1,028
Likes: 1
From: SOUTH ELGIN IL
DeWitts Question - auto or manual
Good morning,
I'm planning to purchase a DeWitts for my '74. Currently I have an automatic transmission but I'm planning to switch to a manual. DeWitt's offers both styles of radiator. I am wondering if I should wait until after making the transmission change to get the radiator because I can get the manual radiator and won't experience any loss of cooling capacity due to the transmision cooler being located inside the radiator. I've got a ZZ4 now but the plan is to either supercharge an engine or go with a huge cube BB down the line.
Thinking as I type, I suppose I could order the manual trans radiator and mount an external trans cooler that I could then remove...
I'm planning to purchase a DeWitts for my '74. Currently I have an automatic transmission but I'm planning to switch to a manual. DeWitt's offers both styles of radiator. I am wondering if I should wait until after making the transmission change to get the radiator because I can get the manual radiator and won't experience any loss of cooling capacity due to the transmision cooler being located inside the radiator. I've got a ZZ4 now but the plan is to either supercharge an engine or go with a huge cube BB down the line.
Thinking as I type, I suppose I could order the manual trans radiator and mount an external trans cooler that I could then remove...
Instructor
Joined: May 2008
Posts: 154
Likes: 3
From: Indiana
May want to pose the question to DeWitts directly. (may be a slight conflict of intrest) We have plenty of folks here running the radiators with auto and 383, 427 SB. In fact I believe the radiator for the 68 is the same for BB and SB. If that's the case I think the cooling capacity will be plenty, with or without the trans cooling coils.
Le Mans Master
Joined: Oct 2007
Posts: 7,455
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From: RI, Now Franklin/Nashville TN
I replaced my OEM radiator with a Dewitts a few months ago and asked the same question since I was thinking that even though I have a 4 speed I could go with the automatic radiator for more cooling capacity and was told by Dewitts that they both have the same cooling capacity, no difference. Call and ask directly if you want.
Team Owner
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Thread Starter
Burning Brakes
Joined: Apr 2007
Posts: 1,028
Likes: 1
From: SOUTH ELGIN IL
Le Mans Master
Joined: Oct 2007
Posts: 7,455
Likes: 977
From: RI, Now Franklin/Nashville TN
If you do mount an external oil cooler separate from the radiator, I would make sure that the cooler is a double stack cooler like Long and the biggest GVW rating that you can fit in the grill, double stack are much more efficient than tube and fin design. With a mechanical fan you do not have to be concerned with airflow all the time like I do with my 1994 mustang GT (with a 28,000 GVW cooler separate from the radiator) and in my 2001 Pontiac Grand Prix (2 separate 18,000 GVW coolers after the radiator) since in the GP the fans almost never run unless the coolant temperature gets over 210 degrees, which is rare and I drive that car in the winter.
Racer
Joined: Oct 2008
Posts: 255
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From: Michigan
The oil coolers are located inside the end tanks and the amount of fluid one would displace is not going to effect the cooling whatsoever. These coolers are not connected to the cooling system at all, they just sit inside the radiator tank. So the pressure they run at isn't related to the rating of the radiator, in fact, you don't even have to plug them when you are not using them as many people think. Nothing in -nothing out
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May want to pose the question to DeWitts directly. (may be a slight conflict of intrest) We have plenty of folks here running the radiators with auto and 383, 427 SB. In fact I believe the radiator for the 68 is the same for BB and SB. If that's the case I think the cooling capacity will be plenty, with or without the trans cooling coils.
Thread Starter
Burning Brakes
Joined: Apr 2007
Posts: 1,028
Likes: 1
From: SOUTH ELGIN IL
There can be difference. Mine is currenlty a 4 core monster of a radiator but I get no flow through the core when I look inside and rev the engine. I'm trying some radiator cleaner that I will then flush and see if it helps. I would bet I need at least need some electric fans though... will probably just do the whole thing
Edit: so if anyone wants my existing let me know...
Edit: so if anyone wants my existing let me know...
Last edited by Dantana; Jul 30, 2009 at 06:41 PM.
Burning Brakes
Joined: Aug 2005
Posts: 1,164
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From: Europe, France
There can be difference. Mine is currenlty a 4 core monster of a radiator but I get no flow through the core when I look inside and rev the engine. I'm trying some radiator cleaner that I will then flush and see if it helps. I would bet I need at least need some electric fans though... will probably just do the whole thing
Edit: so if anyone wants my existing let me know...
Edit: so if anyone wants my existing let me know...
Did you try that with the engine at normal operating temperature ?
The only way to be sure would be to remove the thermostat first. Then if you still don't see any flow when you rev the engine, you have a real problem.
Thread Starter
Burning Brakes
Joined: Apr 2007
Posts: 1,028
Likes: 1
From: SOUTH ELGIN IL
I have tested at both full operating temp and then removed the thermostat and tested- no improvement, extremely low flow.
Also, I should note that I have never had any fluid in my overflow resevoir. I changed the cap to a 16lb and made sure the lines are clear and even when I run up to 220F+ the resevoir is dry
Also, I should note that I have never had any fluid in my overflow resevoir. I changed the cap to a 16lb and made sure the lines are clear and even when I run up to 220F+ the resevoir is dry
Last edited by Dantana; Jul 31, 2009 at 09:38 AM.
Burning Brakes
Joined: Aug 2005
Posts: 1,164
Likes: 1
From: Europe, France
I have tested at both full operating temp and then removed the thermostat and tested- no improvement, extremely low flow.
Also, I should note that I have never had any fluid in my overflow resevoir. I changed the cap to a 16lb and made sure the lines are clear and even when I run up to 220F+ the resevoir is dry
Also, I should note that I have never had any fluid in my overflow resevoir. I changed the cap to a 16lb and made sure the lines are clear and even when I run up to 220F+ the resevoir is dry
How do you fill the block and the radiator ?
