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Using horsepower to gauge the effectiveness and "rate" a radiator is one of the most ridiculous things I have ever heard........
If the stock radiator can't cool your setup....it is not the radiators fault.....trust me on this.
By a direct fit DeWitt unit or equivalent.....
Actually...buy what ever you want....but if a radiator is too effective for your setup, you will just drive around with the thermostat either closed or partially open.
Take a huge tip and buy the highest quality fans you can afford.......one curved blade fan can easily outperform two cheap *** straight blade units......good fans draw less power too.
The stock clutch fan works very well.......consider keeping it.
Jebby
Last edited by Jebbysan; Oct 19, 2020 at 08:25 AM.
i'm worried about that too. as crazy as this sounds i think i have enough clearance to put it back the way it was WITH the electric fan. i bought a slim. lets' see. cross fingers it's good.
i ordered the 17" derale. the champion radiator and shroud. i have to cut the 16" opening on the shroud to fit the 17" why didn't i buy a 17" derale shroud? because it only covers maybe 50% of the rad. pray for me my friend. lol.
Leaking radiator on my ‘78!! Just replaced with DeWitts and electric fans. Overkill for this unknown crate engine, but building-in capacity for a bigger engine.
wow!! looks great. where do you draw power for the fans? also did you tap into the 12v on the compressor so when you turn the air on, hot or not on the rad, it kicks the fan on?
Fan power from alternator. Power to relays from windshield wiper motor. Additional relay goes to green wire on compressor; turns the fans on whenever the ac is on.
The wiring on the fender wall is a combo of fan wiring and Nevernight xenon headlight harness (also to the back of the alternator-140amp dual-rectifier).
FYI - my setup.
Summit Radiator and Mark VIII fan. Fan shroud assembly covers the full radiator finned surface. Fan, with or without the radiator, comes up and out the topside.
I painted that crossmember "haze grey and underway" and it seems to me that it makes the area look better.
Fan is powered from the 140-amp CS-144 alternator output side.
Fan is controlled by temp via EZ-EFI 2.0, A/C in operation, and/or a Manual Override inside passenger compartment.
Relay(s) are mounted on driver side outboard of the alternator.
FYI - my setup.
Summit Radiator and Mark VIII fan. Fan shroud assembly covers the full radiator finned surface. Fan, with or without the radiator, comes up and out the topside.
I painted that crossmember "haze grey and underway" and it seems to me that it makes the area look better.
Fan is powered from the 140-amp CS-144 alternator output side.
Fan is controlled by temp via EZ-EFI 2.0, A/C in operation, and/or a Manual Override inside passenger compartment.
Relay(s) are mounted on driver side outboard of the alternator.
Got the radiator shroud and 17” Derale in and ready to mount. Had to modify shroud hole from 16 to 17” to accommodate the fan. I’m going to add rubber edging to seal the fan cut out. Need to get the upper and lower hoses (don’t want to reuse the old and I can’t even get the lower off. Here’s my question: when I reconnect the transmission lines to the radiator, am I adding sealant tape? White loctite? Or nothing?
Last edited by michael lamoglia; Nov 1, 2020 at 09:40 PM.
i'm going nuts i've ordered a few hoses already and non fit. lower and upper. the new rad is 1 3/8 up top and bottom is 1 5/8 while the neck and pump are standard. any ideas? ahhhhhhh.
i'm going nuts i've ordered a few hoses already and non fit. lower and upper. the new rad is 1 3/8 up top and bottom is 1 5/8 while the neck and pump are standard. any ideas? ahhhhhhh.
Try calling Champion to see what hoses they expect you to use. Perhaps a different year Corvette has different radiator barb sizes? I don't know.
I had to cut it to length, but I bought a direct-fit hose from NAPA. Worked fine with the stock pieces.
Is it length, or barb size, or both that are a problem? Can you post some photos?
called champion they tried to sell me those junk aluminum/plastic hoses that everyone complains about. i bought mine direct fit from napa as well. my issue is on the radiator upper, the hose just fits over it way oversized. needs to be tighter. the side that goes to the water neck is fine. then down below both sides are loose, waterpump and rad. what i need it 1 3/8 upper rad to 1 1/2 and lower same thing. i'll post pics tomorrow when the sun is out.
Won't the fan pull air through these vents before trying to pull through the radiator?
excellent question. As a matter of fact I researched this and the reason for it is because when the fan sucks air it creates a vortex of trapped hot air in those locations. That’s why the good shrouds have this. Others sell a kit so you can cut the holes and place rubber grommets that flap open as you drive. Google it up very interesting stuff.
Try calling Champion to see what hoses they expect you to use. Perhaps a different year Corvette has different radiator barb sizes? I don't know.
I had to cut it to length, but I bought a direct-fit hose from NAPA. Worked fine with the stock pieces.
Is it length, or barb size, or both that are a problem? Can you post some photos?
so I went to Napa and got help from a super guru. He told me all these hoses even from custom shops are going off generic OE replacements. He pulled out a book that looked older than me and showed me hundreds of hoses. Quickly he found the ones I needed and showed me I needed inserts. Now get ready for this. He tells me 1 3/8 is unusual and that it’s probably metric I’m measuring. That the industry accounts for this and simply sells these inserts. When we research where these things are made, they say ‘some components overseas’!!!! So much for buying American! No wonder I was going crazy. He had one to show me how it fit and man it made it show .41 MM!!!! Metric! Anyways the two I ordered should be in tomorrow so we’ll see. You should have heard this guy talking. It almost seemed like he wrote the book on this stuff. Good luck for me I hope.
so I went to Napa and got help from a super guru. He told me all these hoses even from custom shops are going off generic OE replacements. He pulled out a book that looked older than me and showed me hundreds of hoses. Quickly he found the ones I needed and showed me I needed inserts. Now get ready for this. He tells me 1 3/8 is unusual and that it’s probably metric I’m measuring. That the industry accounts for this and simply sells these inserts. When we research where these things are made, they say ‘some components overseas’!!!! So much for buying American! No wonder I was going crazy. He had one to show me how it fit and man it made it show .41 MM!!!! Metric! Anyways the two I ordered should be in tomorrow so we’ll see. You should have heard this guy talking. It almost seemed like he wrote the book on this stuff. Good luck for me I hope.
Hmm.. I have the 3 row champion myself in my 74 (6 years old) and it has the stock hoses connected to it for both engine and transmission coolant with no fitment issues. I am well aware the champion rads are made overseas as are most replacement and OEM replacement parts.. Many threads here on that topic as well as cost differences.
Last edited by augiedoggy; Nov 11, 2020 at 09:30 AM.
A lot of people don’t know much about radiators or how they perform, most people still think you need to slow the fluid down in order for there to be time to cool it! Soooo much miss information out there about all these things. Fun fact- single 1” core will out cool a dual 1/2” core. Most radiators you see that are 3-4 core have tiny 1/2-5/8” cores and you can tell because it will say 4 cores but the core width is only 2.5”. Now when you have multiple cores you need gaps between cores so a 3 core has 2 gaps between the outer and inner core. Basically you lose cooling surface area and thus reduce cooling capacity. A dual 1” or 1.25” core is more than most will need for cooling. The larger tubes allow more surface area, less gaps means more cooling surface. A lot of people think they need lots of cores and they are wrong. You want a rad that has enough cooling while still allowing air to pull through easily. When you increase core thickness you add restriction which means air will have a harder time making its way through. This also means that your fans have to work harder to pull air through and guess what? Fans especially electric are mostly grossly over rated CFM wise and they operate just like a fuel pump. Restriction on the fan side to pull air through a thick core reduces the CFM of the fan and almost all manufactures besides Spal and derale test fan CFM open air (not against a rad and having to pull through a restriction) they call this static pressure. As the pressure increases fan CFM drops like a rock. A easy way to tell is how many amps the fan pulls, so every 10amps is worth about 1000cfm ish as a rule of thumb. Now people slap in 3” core radiators and there cooling is improved but they are hurting themselves more than helping. 3” core thickness needs some SERIOUS fans to work as intended. Also what are the limits of cores and HP? Well it’s not that easy, be cool will use a dual 1” core rad with a set of fans and rate it to 400hp, they sell another that’s good for 600hp... guess what the difference is? The fans!!! The radiator doesn’t change and they just put better fans that pull more air. There is a reason the OEMs use single core 1-1.25” thickness cores and they can cool 400-500hp motors with AC, the radiator is very efficient bc air can pass through it easily and OEM fans are some of the best you can buy. They spend millions designing and testing cooling system components... something that be cool and the other brands just can’t compete with. If you want to get the max cooling with the space available on these cars get a dual 1” core radiator and slap on a good single 2 speed OEM fan or high end SPAL or Derale or get a dual fan setup from both or OEM. Get a veritable speed controller with soft start or make your own dual speed GM controller with 3 relays. If you have good fans your looking at 20-30amps running and spike will
be higher like 30-50amps easily. With that being said a 2 row 1” core radiator and a good set of fans will
easily cool 600hp all day in 100*F heat. You also
want the coolant to flow as fast as possible through the rad and engine so a high flow waterpump is always a good idea.
my experience has been at least 5 different setups
and cars which all make 500-750hp and are only street driven in hot 80-100*F high humidity weather. I only run 2 row 1” cores and always get the best fans I can with integrated shroud of some kind covering 80% or more of the core. I’ve run be cool, Howe, afco racing, griffin, champion etc and they all
work well. Fans have been OEM Mark IIV, new 08+
charger, Chevy traverse (perfect fit for a 31x19 rad with 27” core) and then I’ve run spal, derale and some legit knock off spals. I always test my fans with a high accuracy DC meter which tells me amps, watt power and other info so I know what they pull at startup and running to size wiring and fuse correctly. My favorite was the mark VII and my turbo LS firebird that runs derale shroud with dual spal 13” high output on a soft start variable controller. With alot of hot turbo piping under the hood and a afco racing 2 row 1” core rad I can have my LS run 165-185 no mater the outside temp which it has a 160tstat that I tested opens at 173*F. So it basically Bounces around with the Tstat opening and closing. That car makes 750hp at 15psi and I street drive it at 13psi everytime it’s on the road and I drive it like I stole it.
sorry for the rant, if you were sub 450hp you could run a single 1” row core and probably be fine with some decent fans. Im referring to aluminum radiators and not copper.
hi there. Got everything in. Burping the radiator but it seems the new thermostat I bought isn’t opening. Shows 185degrees to open and I got the engine up to 200 and still not opening. I have the burping funnel sitting there waiting for air to come out and nothing. The water in that funnel is hot with a thin layer of smoke. Any ideas? Also fan only kick on with a/c compressor. Otherwise won’t kick on at high temp. It’s factory set to open at 165 derale
hi there. Got everything in. Burping the radiator but it seems the new thermostat I bought isn’t opening. Shows 185degrees to open and I got the engine up to 200 and still not opening. I have the burping funnel sitting there waiting for air to come out and nothing. The water in that funnel is hot with a thin layer of smoke. Any ideas? Also fan only kick on with a/c compressor. Otherwise won’t kick on at high temp. It’s factory set to open at 165 derale
I bought 2 bad thermostats before buying a good one... 80% of the different brand names are all made by the same manufacturer as well. if the thermostat doesnt open your not getting flow past the temp sensor to kick on the fan right? maybe thats all it is.
Last edited by augiedoggy; Nov 21, 2020 at 03:10 PM.
You can test your thermostat on the stove if you are concerned. More likely, you have a trapped air bubble. I drill a small hole in my thermostats to help with the burping, YMMV.
Try this instead.
With the nose of the car elevated (on ramps, for example), and the waterneck removed, fill the engine through the intake manifold. The radiator will half-fill through the lower hose. Rock the car back and forth, and fill it right to the top, getting air bubbles out of the engine. Install the thermostat, expensive gasket, and waterneck. Then fill the radiator the rest of the way (and overflow tank).
