Need a very serious radiator!
Thread Starter
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Joined: Jul 2010
Posts: 97
Likes: 12
Need a very serious radiator!
Hi guys,
1987 C4 Corvette, standard trans.
600 plus horse Big Block!
Mojave Desert --> 130 degrees in the shade!
A/C obviously a must.
Want engine temps well under 200.
Please guys, no lectures on airflow, fans, etc. I get it, I really do.
Unfortunately, I really am on a tight budget. I don't think a "drop in" instant fit radiator will work, and a universal type radiator should be cheaper--> I'm prepared to do work both to save money, and to get very best cooling.
To show my dedication to getting this to run cool though, I am considering ripping everything out to make the "gills" airflow functiinal, and maybe even installing auxiliary mini-radiators there.
I don't mind fabrication or modification.
Thanks!
Vettepilot
1987 C4 Corvette, standard trans.
600 plus horse Big Block!
Mojave Desert --> 130 degrees in the shade!
A/C obviously a must.
Want engine temps well under 200.
Please guys, no lectures on airflow, fans, etc. I get it, I really do.
Unfortunately, I really am on a tight budget. I don't think a "drop in" instant fit radiator will work, and a universal type radiator should be cheaper--> I'm prepared to do work both to save money, and to get very best cooling.
To show my dedication to getting this to run cool though, I am considering ripping everything out to make the "gills" airflow functiinal, and maybe even installing auxiliary mini-radiators there.
I don't mind fabrication or modification.
Thanks!
Vettepilot
Safety Car
Joined: Aug 2002
Posts: 3,842
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From: SANTA CRUZ CA
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
I think Aux radiators in a C4 is a good idea. IDK that the "gills" will flow enough, unless you cut more slits into them?
I've always thought that the spare tire carrier would be a great location for an 2nd radiator. Ditch that thing, mount a large radiator horizontally in the rear and I'd think that the air flow over it, at speed would add a significant amount of heat rejection. Added capacity for that part of the loop would help slow temp rise at stop/idle even w/o a fan on it.
I've always thought that the spare tire carrier would be a great location for an 2nd radiator. Ditch that thing, mount a large radiator horizontally in the rear and I'd think that the air flow over it, at speed would add a significant amount of heat rejection. Added capacity for that part of the loop would help slow temp rise at stop/idle even w/o a fan on it.
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
I'm kidding, of course.
Pro
Joined: Sep 2019
Posts: 716
Likes: 135
From: Buchanan, Michigan
Dewitts, be ready to drop some coin, they can custom make you a rad that will fit in the stock location and be a 3 pass etc. Until you get over 400 rwhp the stock radiator is actually pretty good.
Safety Car
Joined: Apr 2005
Posts: 3,624
Likes: 431
From: Dale City VA
KKS 3 row radiator off Ebay. $215.00
I ran one in my 785hp 84 drag car for years. Biggest problem I had was keeping any temp in the engine. I even used it's internal cooler for my TH350 and later Powerglide with 4500 and 6000 stall converters. I drove the car on the street often and it always ran cool (under 180F). Of course electric water pump and no thermostat. Excellent radiator for the cost.
Will
I ran one in my 785hp 84 drag car for years. Biggest problem I had was keeping any temp in the engine. I even used it's internal cooler for my TH350 and later Powerglide with 4500 and 6000 stall converters. I drove the car on the street often and it always ran cool (under 180F). Of course electric water pump and no thermostat. Excellent radiator for the cost.
Will
Thread Starter
Advanced
Joined: Jul 2010
Posts: 97
Likes: 12
Thanks guys. I read all references and links. Keep 'em coming. Actual experience reports are great.
Engine is an honest 550 horse 454, already built and waiting for install. I'm presently working on various upgrades on the car, such as the radiator situation, in anticipation of being ready to throw the big block in. I haven't decided whether to use the old V belt drive setup, modified as necessary, or to adapt the small block serpentine drive to the big block. I've read articles on that and it's not too tough, but finding an aluminum, high flow, short water pump in reverse rotation for the BBC might be a challenge.
Vettepilot
Engine is an honest 550 horse 454, already built and waiting for install. I'm presently working on various upgrades on the car, such as the radiator situation, in anticipation of being ready to throw the big block in. I haven't decided whether to use the old V belt drive setup, modified as necessary, or to adapt the small block serpentine drive to the big block. I've read articles on that and it's not too tough, but finding an aluminum, high flow, short water pump in reverse rotation for the BBC might be a challenge.
Vettepilot
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Brett Foote
Team Owner
Joined: Aug 2004
Posts: 21,543
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From: Park City Utah
KKS 3 row radiator off Ebay. $215.00
I ran one in my 785hp 84 drag car for years. Biggest problem I had was keeping any temp in the engine. I even used it's internal cooler for my TH350 and later Powerglide with 4500 and 6000 stall converters. I drove the car on the street often and it always ran cool (under 180F). Of course electric water pump and no thermostat. Excellent radiator for the cost.
Will
I ran one in my 785hp 84 drag car for years. Biggest problem I had was keeping any temp in the engine. I even used it's internal cooler for my TH350 and later Powerglide with 4500 and 6000 stall converters. I drove the car on the street often and it always ran cool (under 180F). Of course electric water pump and no thermostat. Excellent radiator for the cost.
Will
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
KKS 3 row radiator off Ebay. $215.00
I ran one in my 785hp 84 drag car for years. Biggest problem I had was keeping any temp in the engine. I even used it's internal cooler for my TH350 and later Powerglide with 4500 and 6000 stall converters. I drove the car on the street often and it always ran cool (under 180F). Of course electric water pump and no thermostat. Excellent radiator for the cost.
Will
I ran one in my 785hp 84 drag car for years. Biggest problem I had was keeping any temp in the engine. I even used it's internal cooler for my TH350 and later Powerglide with 4500 and 6000 stall converters. I drove the car on the street often and it always ran cool (under 180F). Of course electric water pump and no thermostat. Excellent radiator for the cost.
Will
Got any idea what brand KKS is? Do they sell other "good" stuff?
Melting Slicks
Joined: Mar 2002
Posts: 2,876
Likes: 764
From: Sligo PA
The Griffin Racing 1-25241-X fits the early C4's without too much issue. You need to trim the upper and lower shroud a little. I made new rubber feet for mine to set in. I don't have AC in my car. But I think it should fit fine with AC being that your car is a standard so you don't also need a trans cooler like I do. But the Griffin radiator is made in the USA and is only $200 shipped. Also the thing is 3" thick so cooling is very good. I run mine with the factory fan with no issues.
Also my Vette is a street car. It does very well for me with a built motor in traffic.
Also my Vette is a street car. It does very well for me with a built motor in traffic.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
go overkill on your fans...OEM fans kick **** and last forever. Luxury car, truck, etc.
I never see heat management mentioned.
-Adapting a ZR-1? Fan shroud to a C4 with the hole in the hood? No clue if it would fit.
Open up those gills
Let some pressure out from under the hood..maybe get creative with some 'glass vents of some type.
Integrate an isolate cold air deal for your engine at the same time
Not those cheesy black plastic stick on deals you see. That could be fun. Had a few big blocks, they are one giant heat sink
but SO worth it..that torque is addicting. I have a SBC at roughly that power level, different car with better airflow than a C4
with one of those 16" spals...not adequate. There are brushless "smart" fans out those are super efficenet, nice. You could have some fun with this project.
Post up when youre done. Im in so Cal too...how in the hell are you gonna smog it? Please share. Im in Hemet gets fn hot out here not like Mojave though.
Edit Noticed MB uses an almost false 2nd firewall that isolates the braking system and more from heat. Another option to think about.
I never see heat management mentioned.
-Adapting a ZR-1? Fan shroud to a C4 with the hole in the hood? No clue if it would fit.
Open up those gills
Let some pressure out from under the hood..maybe get creative with some 'glass vents of some type.
Integrate an isolate cold air deal for your engine at the same time
Not those cheesy black plastic stick on deals you see. That could be fun. Had a few big blocks, they are one giant heat sink
but SO worth it..that torque is addicting. I have a SBC at roughly that power level, different car with better airflow than a C4
with one of those 16" spals...not adequate. There are brushless "smart" fans out those are super efficenet, nice. You could have some fun with this project.
Post up when youre done. Im in so Cal too...how in the hell are you gonna smog it? Please share. Im in Hemet gets fn hot out here not like Mojave though.
Edit Noticed MB uses an almost false 2nd firewall that isolates the braking system and more from heat. Another option to think about.
Safety Car
Joined: Apr 2005
Posts: 3,624
Likes: 431
From: Dale City VA
What fan did you run with that? FWIW, I tried a 160-stat for a bit and think it stuck open. In the winter, it wouldn't get above 130 on the hwy. Without A/C, it would take quite a bit to "heat up" and really only when I was running A/C. So, the fan might be good to know...as well as the length of "street runs". Gotta assume no A/C on a drag car.
Got any idea what brand KKS is? Do they sell other "good" stuff?
Got any idea what brand KKS is? Do they sell other "good" stuff?
Far as I know KKS Motorsports is the brand. I don't know what else they sell. It was the only inexpensive big direct fit C4 radiator that has stamp formed end tanks... honestly that was the reason I chose it over a Champion or other imported radiator with welded flat sheetmetal tanks. I had used a Champion in my wife's 79 C3 and while it cooled well it didn't fit the factory brackets worth crap.
If you look at my other posts, I just converted the 84 to a lightweight G Plus brand Civic radiator. I put the KKS C4 radiator up in the rafters of the shop just in case I ever decide to put the 84 back on the street.
Will
