Stock radiator replacement/upgrade?
Thread Starter
Le Mans Master
Joined: Jun 2004
Posts: 6,231
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From: Seattle WA
St. Jude Donor '14
Stock radiator replacement/upgrade?
I've verified a coolant leak in my stock radiator in my 2003 Z06. Is there a recommended upgrade over the stock replacement? I'd want a "plug and play" fit, and the 'Vette is totally stock, so I don't need something crazed 
Thanks!
Thanks!
Instructor
Joined: Aug 2012
Posts: 227
Likes: 12
From: Southern NJ
if i were replacing my radiator it would be with a Dewitt's unit, stock or not. its pricey but i think it's worth it. I am planning to replace it this winter and that is what i am getting. maybe it's overkill but makes sense to me.
Last edited by Vetteman Jack; Aug 30, 2018 at 05:47 PM.
Thread Starter
Le Mans Master
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
Thanks - I wasn't clear from their website if it was truly "direct fit", i.e. if it worked with the stock fan, etc...?
Last edited by Vetteman Jack; Aug 30, 2018 at 05:48 PM.
Race Director
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From: Hickory NC
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Agree with Vinny. Although more expensive than a factory replacement, I like the fact that the side tanks are also aluminum rather than plastic, which makes it easier to repair minor leaks IF you were to ever get one. The materials in the DeWitts radiators are also thicker and the welds appear much cleaner. Adding the Spal dual fans is also a good idea to maximize airflow through the radiator. You can always add the radiator now, and then upgrade to the Spal fans later on to spread out the costs of the parts.
Many people also seem to like the Ron Davis radiators, however, they can be as much as twice the price of the DeWitts and I'm not sure about any added benefits over the DeWitts. I've also known of a couple of C5 owners who are using Griffiths radiators made in South Carolina that were pleased with those units.
So far, the few people I've met that were using any of the China made, lower cost aluminum radiators (found on eBay and other places) were not satisfied in the long run. They've complained of pin hole leaks or weak welds showing up in as little as a year's time. It's possible that you could luck into a good one, but it seems risky to me.
Of course, if you're just needing a replacement radiator for your 15 year old stock radiator, that suggests Chevy did a good job with the development of their radiator. I just tend to go a little overboard on replacement parts I use.
Best wishes with your search for the right radiator for your Z06.
Last edited by Vetteman Jack; Aug 30, 2018 at 05:49 PM.
Le Mans Master
Joined: Oct 2010
Posts: 7,373
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From: cold & windy
a few years back, i had a couple guys recommend the SpeedCooling unit.
https://www.speedcooling.com/1997-20...-Radiator.html
any other folks have experience with this one? i'm starting to look for a DeWitts alternative myself.
https://www.speedcooling.com/1997-20...-Radiator.html
any other folks have experience with this one? i'm starting to look for a DeWitts alternative myself.
Race Director
Joined: Apr 2017
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From: Hickory NC
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a few years back, i had a couple guys recommend the SpeedCooling unit.
https://www.speedcooling.com/1997-20...-Radiator.html
any other folks have experience with this one? i'm starting to look for a DeWitts alternative myself.
https://www.speedcooling.com/1997-20...-Radiator.html
any other folks have experience with this one? i'm starting to look for a DeWitts alternative myself.
https://www.google.com/url?sa=t&rct=...3qet10CjZbC82j
https://www.google.com/url?sa=t&rct=...B0VubARELwU2Et
https://www.google.com/url?sa=t&rct=...cjuoDxYBK7Hrnr
https://www.google.com/url?sa=t&rct=...mQiYIxKtonWyux
https://www.google.com/url?sa=t&rct=...U68edYpBpwrj9Z
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do you plan to mod the car?... if not just go with another oem radiator in my opinion... sure the dewitts is a nice radiator (I have one myself) but for a stock car there really is no need for it to justify the price difference... the stock radiator lasted 15 years and another one would likely outlast the time you own it
Burning Brakes
Joined: Jul 2011
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From: Fredericksburg Virginia
I am running the ECP radiator on my 402 supercharged 99 and have had no issues with leaks or cooling. As with any product it can be hit or miss. I also have a buddy with a 99 and has also been running the same radiator for over 5 years no issues. It's hard to gauge without knowing how many have been sold and how many complaints. Just because there are a few complaints does not mean they are garbage. There may be 500 great experiences and 2 bad ones. If you don't hear about anything but the bad ones then it is misrepresented as a bad product. I say buy what you want. I saved money and invested into other parts.
Drifting
Joined: Nov 2005
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From: NW Chicago
St. Jude Donor '12-'13-'14-'15
I have an ECP radiator, that has been in the car for a year now. No issues so far. I live not to far from their warehouse in Chicago and picked it up in person. They said it is warrantied for life, just don't modify it in any way. I also installed an anode rod, which they sell, in the drain port instead of the drain. For the price I figured it was worth a try, my old radiator was a Fluidyne, tuner installed, lasted 17 years. I have nothing against the other manufactures and probably would of used a Dewitts, since Fluidyne would have to make the unit, copied off of my old that I would have had to send them. To much time and hassle. With ECP being local, I went with it.
Racer
Joined: Sep 2012
Posts: 369
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From: North Georgia
I have replaced my radiator in my 2003 ZO6 with a Dewitt's. It is a direct fit and I was able to do the install myself. It fits perfectly. Unfortunately, there is no longer a space between it and the fan shroud where I used to use an extension wand attached to my compressor to blow out debree. I've got to figure out a quick release on the fan shroud to extract it so I can clean the radiator from the back.
I would make the purchase it again.
Spaggs
I would make the purchase it again.
Spaggs
Thread Starter
Le Mans Master
Joined: Jun 2004
Posts: 6,231
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From: Seattle WA
St. Jude Donor '14
I had the good fortune to be able to look at the Dewitt's this morning; it's an outstanding piece of quality engineering to be sure, and an excellent value for the price.
FWIW, I did make the decision to roll the dice with a NAPA replacement. I can hear some muttered "idiot!" in the background, and that's kinda fair But I do have no plans to upgrade the engine in the near future and - once I learned to keep the fins clean - had no overheating issues. It is the same "meh" construction as the factory piece, so we'll see.
Sincerely appreciate all the feedback. If this turns out to be a bad call I'll post back here to save someone else the pain.
FWIW, I did make the decision to roll the dice with a NAPA replacement. I can hear some muttered "idiot!" in the background, and that's kinda fair
But I do have no plans to upgrade the engine in the near future and - once I learned to keep the fins clean - had no overheating issues. It is the same "meh" construction as the factory piece, so we'll see. Sincerely appreciate all the feedback. If this turns out to be a bad call I'll post back here to save someone else the pain.
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I agree with the others - go with a DeWitts radiator.
Race Director
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Dewitt's is a fantastic replacement for OEM. I know many probably can't justify replacing an OEM with a pricier aluminum one but, I look at the cooling aspect of it and superior build quality over the OEM. Great upgrade to do and be done with it. At least Dewitt's is reasonably priced for what it offers. You want to talk pricey, look no further than a Ron Davis radiator, which is excellent but, that baby ain't cheap.
