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Smallest radiator for a turbo 5.3?

Oddball

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I have roughly a 22x22 opening for a radiator. How thick of a core will be sufficient to keep this puppy cool? Puller fan(s), condenser, intercooler and oil cooler in front. 8274 ahead of that.
 
The 69 camaro of winches ! Or the 350 sbc… whichever floats your boat !
 
Electric fans are not going to do it unless you run the high dollar EFE fans. Even then I would question its ability to pull enough air through a thick core. Mechanical fan wins here.

Going thicker on the core does not increase cooling capacity like larger cores do.

You have about the worst conditions possible, good luck.
 
Electric fans are not going to do it unless you run the high dollar EFE fans. Even then I would question its ability to pull enough air through a thick core. Mechanical fan wins here.

Going thicker on the core does not increase cooling capacity like larger cores do.

You have about the worst conditions possible, good luck.
Brutally honest, and I appreciate it. What about a " dual pass" rad? I assume it's like two rads in one. I figured a thick core would give me more coolant to cool, and more in the core at any given time. I could put the clutch fan back on. But then the hot side would be quite convoluted. I'm starting to think of ways to run two rads in series. One in front and one against the hood like a top mount IC but off to the passenger side. This is getting more complicated by the minute.
 
Dual pass is better. If you can get some of the shit out from in front of it, that would help a lot.

Shielding around the radiator will help also. Make sure the air that goes through the radiator isn't doing laps through it.
 
Dual pass is better. If you can get some of the shit out from in front of it, that would help a lot.

Shielding around the radiator will help also. Make sure the air that goes through the radiator isn't doing laps through it.
At this point, AC is a pipe dream until i can fit a compressor. So the condenser might get turfed. I could get creative with the oil cooler to move it out of the way. I have plans for extensive ducting and shielding. I need to be able to bomb through anything without issue. So the hot side and turbo will be high up with heat shielding all round, and well separated from the cold side. The rad will have atleast expanded steel infront of it, but probably vanes like a bike, to keep mud and branches out. There will be shielding between the frame rails and wheel wells to completely separate the engine bay from splash. I need to make/get a loovre punch set and go to town on the inner wells and hood. All the loovres will face backwards to let heat out and not scoop water in. I'm still spit-ballin here but now is the time to plot it all out and have a clear plan. I picture opening the hood and seeing a large shield that goes from the top rad support, all the way to the firewall, with nothing but exhaust above it.
 
I have a 28x16 rad, dual pass, dual 1.5" row and it will not keep a stock 5.3 cool if you're romping on it (race pace).

IDK how you plan to keep that cool with a 22x22 opening unless it's a red light to red light car.


I agree on mechanical fan, unless you can / want to spend the money on a Brushless setup.
 
I run a Griffin 28202 in my 6.0L(LQ4) swapped FJ55:
Core is 19"x19" with overall width of 24". It is 2 1" tubing cross flow.

I use the cooler for the engine oil since I run a manual trans. It is mostly a stock LQ4 with a mild cam and mild tune so probably south of 400hp by a bit but I'd say much more north of the stock 325 hp ;) I use the stock mechanical clutch fan setup with NO fan shroud. It is also blocked with an AC condenser and a lower mounted 8274.

I have NEVER had it go above 215 degree... it doesn't matter if it was 100 outside or not. It also didn't matter how much I had the pedal on the floor. Freeway speed.... stop and go.:eek:
Winch1_sml.JPG

This is before the condenser got stuffed in there:
front_clip2_sml.JPG

I did eventually put a finger guard to protect from the fan:
finger7.jpg

If you look at the above just above the first "above" in the sentence, you can see the condenser fitting ;)

That said, I went a bunch wider on the bigger cruiser that got the turbo 5.3L... no idea if it is enough :(
 
A radiator that small simply will not be able to cool that motor continuously except at idle and cruise. Luckily it's installed in a toy that will spend basically all its time at idle or close to it and not a work truck that's gonna get floored up a grade.

I would run the best fan and shroud that you can (i.e. a mechanical one, probably without a clutch to start) and if you have overheating problems when you stick your foot in it then find a way to add coolant capacity to the system to give you more time with your foot in it before the temp gets too hot.

The turbo is gonna dump a bunch of heat into the system so keep that in mind when reading about what the "LS in a small car" guys consider sufficient.

Going thicker on the core does not increase cooling capacity like larger cores do.
Going thicker increases cooling capacity, just less efficiently for the space and mass used.
 
I plan to run this truck pretty hard. It will see a lot of low speed trails, rock crawling, doughnut land activities. I'd like to stay out of the mud bogs but I'm a bit of an animal. I need to build it for the worse case senario. So it seems two rads will be necessary. Thanks for the valuable info and direction guys. Stupid me for tossing out the mech fan. Figured I would never need/want that thing.
 
I plan to run this truck pretty hard. It will see a lot of low speed trails, rock crawling, doughnut land activities. I'd like to stay out of the mud bogs but I'm a bit of an animal. I need to build it for the worse case senario. So it seems two rads will be necessary. Thanks for the valuable info and direction guys. Stupid me for tossing out the mech fan. Figured I would never need/want that thing.
Everyone says that but realistically how much time are you spending with your foot in it when you have 300-500hp in a Jeep CJ sized vehicle?

Unless you're mud bogging I'd bet the answer is not much.
 
You need to focus on getting the air out that you pull in plus the additional heat. Hole saw bug holes in your inner fenders, raise the rear of the hood a 1/2", vents or something.
Make sure you force all the air through the cooling pack. Make sure each part has at least an inch of airspace between it and the next. So a rad condenser and intercooler stacked combo instantly losses 3". Use foam and or baffles to do this. Get that stuff sorted out before you think about cooling fans. Mechanical or electric.

There is no need to run a second radiator. You need one radiator and put it somewhere that it's gets cool clean air.

Here is what I suggest.
Find the largest rad that you can afford. Then find a new home for it out back. Close behind the cab just above the engine is a great place. Going down the highway that area has a slight vacuum and will assist in getting the hot air away.

If you can not get the proper sized rad in place there is a stop gap.

Then you need to rethink your fan control strategy. You need to run your fans a bit longer to further raise your rads BTU reserve. In other words you need to extend the fan on time once the coolant meets temp. I use time delay relays from McMaster. Automation direct has some. Once my fan switch target is met the relay receives the off signal (let's say 180 degree's). At this point my relay keeps the fans running for how ever longer in time that I select. IIRC my crawlers fans are set to run 5 minutes after the off signal.

This helps give you a cushion of temp. How many degrees you get from this and if it works I can't promise. But I've done that on my crawler with a stock drivetrain and never overheated driving in NYC traffic or in the trails.
 
Agreed.
Then you need to rethink your fan control strategy. You need to run your fans a bit longer to further raise your rads BTU reserve. In other words you need to extend the fan on time once the coolant meets temp. I use time delay relays from McMaster. Automation direct has some. Once my fan switch target is met the relay receives the off signal (let's say 180 degree's). At this point my relay keeps the fans running for how ever longer in time that I select. IIRC my crawlers fans are set to run 5 minutes after the off signal.

This helps give you a cushion of temp. How many degrees you get from this and if it works I can't promise. But I've done that on my crawler with a stock drivetrain and never overheated driving in NYC traffic or in the trails.
Way to make it a lot more complex vs telling the ECU to turn the fans off at a lower temp.
 
That's for you rich folks. Some of us poor's are stuck without and ECM. Lol
 
Terminator X. Cruising trails, there will little air flow. I can't see building much boost in low. But if I'm out on the flats drifting around and spinning doughnuts, I bet it will get hot. Getting stuck in traffic shouldnt be a big deal. But it could. Pulling 4th gear up some of the wicked highways we have here can be hard on a regular car. Add a trailer and manifolds could start to glow. I'm still thinking two rads would be my best bet. I can make room for a 10x18.
 
I agree with angry... big radiator with big fans in the rear. It will be tough but it will be better in the long run
It's a pickup truck with a canopy. I can put my dog back there, or sleep in it when camping. Maybe even haul a load of gravel or fire wood. No can do on the rear mount rad. Just the thought of punching holes in the box is cringe. It is the most effective idea for sure.
 
It's a pickup truck with a canopy. I can put my dog back there, or sleep in it when camping. Maybe even haul a load of gravel or fire wood. No can do on the rear mount rad. Just the thought of punching holes in the box is cringe. It is the most effective idea for sure.
Then on the roof:lmao:
Yeah that does make it tough when you actually use the bed for real truck things. I hope you can keep it cool.
 
I tried or I should say I have the radiator in the rear bed of my Willys truck(I'm now putting my old/new SBC radiator back w/Taurus fan in the front by removing and relocating stuff)--stock radiator with the electric fans(both fans running) and it needs to idle at 1100-1200rpms to keep the temps at 207-210, but the temp drops once you hit 1500-1600 rpms and at 2500 rpms she runs around 194-197. Outside temps have been from the 60*-90* and same results. The rig is just on jack stands, so I don't have any road time info to add. I just know while crawling you are idling a lot and those temps are just not good in my head. Stock truck water pump and I used some 1 1/4" rubber EPDM hose due to routing. I'm not sure if the stock water pump is strong enough at idle to move the water that far or if the friction from the EPDM hose plus the length was too much for the water pump. I won't know if moving the radiator will be better or not as it's smaller, like 1/2 the size of the stock radiator, but I sure hope so, because maybe ditching the EPD hose and running exhaust pipe(less friction, but more joints, but not sure it will make it better or not, so it's gamble, but cheaper than the next two options) or going to a high output(Edelbrock) or electric water pump(Meziere 55gpm style) and keep the radiator in the rear is all the I think I have left for options and each of those options are more and more money. Plus it's a bit ugly in the back with the reservoir back there and it's added plumbing.
 
I have a stock LQ4 with f-body LS1 water pump and thermostat plumbed to a 31x19 radiator in the rear of my buggy with twin electric fans (Derale 16927) with 1.25" silicone hose front to back. Fan 1 is 205 on and 195 off, 2nd fan is 210 on and 195 off. The second fan rarely turns on. Hottest ambient I've had is around 100*F.
 
JohnnyJ--how'd you route the silicone hose? And how you ran the steam line? I'm guessing you used the heater hose delete loop also. My hoses went up to the height of the shock hoop back down and outside the frame rail, made a S bend to get over the frame to inside the frame rail and then 90 up to thru the bed and another bend to get the lower hose to the radiator and the upper hose required 2 more bends. The steam line goes back to the radiator also and the heater hoses make their way to the overflow tank which is in the bed also & routed along side the coolant hoses. To stay away from the headers exhaust I had to do it this way.
 
Heater hose is looped. Steam line runs to the back to radiator. My upper hose had to run over the top of the engine, so I have a remote fill at the high point with higher pressure cap. Cheap eBay overflow in back.
 
JohnnyJ--Thanks for the info, so you pretty much have the same upper hose routing as mine(up/over/down/up) but your lower hose is different and mine is the same as the upper, but yours works and mine doesn't. I have around 11'-12' run on the lower hose and more like 14'-15' for the upper hose. What are your lengths?

Oddball--I'm not trying to hijack your thread, but trying to get some info for you and others on what works and what doesn't.
 
From front of engine to front of radiator is just over 7' (90"). Add a little for routing.
 
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