Is there such thing as a "good" performance aluminum radiator for the TJ?

[Chris]

No worries. I'm also here to learn.

Iirc Banks was getting around 75HP gains with their turbo kit, and 100HP gains once they added in an intercooler. So on the simplist level, it does mean that cooler dense air does equal more power.

Oh yeah... remember those older Volvos back in the day where they would say something like "840 Turbo" on the rear? Then a few years later, you saw ones that said, "840 Turbo Intercooler". Well, I don't think I've ever seen anyone advertise "intercooler", but I suspect they were doing it because they were proud of the extra power it made.

If you run any supercharger or turbo at a high enough psi without any way to cool the air, at some point it's going to become very inefficient compared to what it would be if you were cooling the air. With low boost applications this isn't as noticeable, but when you start running really high boost levels, cooling the air makes a world of difference.

I ran your question by Charles, and here is his official answer (yes, he got back to me very fast):

"HP at the same boost pressure will be more or less the same except for very slight differences in parasitic losses. The main difference in performance is determined by air charge temperature and how the supercharger's boost pressure varies with RPM. Roots supercharger tend to make more boost and power/torque at low rpms then twin screw superchargers do. So boost comes in quicker and at lower engine rpm compared to twin-screws. Magnum Powers superchargers are high performance roots type that out performs Eaton's M90 because MPx90 is a two cycle machine with long port durations that increases volumetric efficiency (delivering 50% more air compared to the M90) at much lower outlet temperatures. Eatons have short port duration because they have a third cycle that reduces noise. Other advantages the Magnum Powers SC kit for the TJ offers is an intercooler and an independent supercharger drive belt system that allows higher boost pressures than any other on the market."

 

[toximus]

@Chris, does he happen to have dyno charts of a stock 4.0 at what he'd consider a safe tune for a daily driver?

I know I'm probably asking a lot for somebody who has zero interest in purchasing (as I have no way of fitting that bad boy under my hood).

 

[Chris]

@Chris, does he happen to have dyno charts of a stock 4.0 at what he'd consider a safe tune for a daily driver?

I know I'm probably asking a lot for somebody who has zero interest in purchasing (as I have no way of fitting that bad boy under my hood).

I'll ask him if he has any dyno charts.

Why can't you fit one under the hood?

He tells me that this kit will add over 115 ft/lbs of torque and 100 hp at the wheels (not at the crank like most others quote).

 

[toximus]

I'll ask him if he has any dyno charts.

Why can't you fit one under the hood?

High lines, 2.5x14" COs, and tranny/steering coolers. There's not much room for anything.

 

[Chris]

High lines, 2.5x14" COs, and tranny/steering coolers. There's not much room for anything.

That's true. Plus this one mounts differently than the Sprintex and Boosted Tech. It basically replaces the entire spot where the stock airbox would go:

 

[mots]

Forgive my ignorance on boosting engines, but on the most basic level won't 9-11 psi of boost provide the same HP and torque increases regardless of what's delivering it?

But again, simply, whether it's a BT M90, Kenne Bell, or this Magnum, isn't the power output the same at the same PSI?

No worries. I'm also here to learn.

So on the simplest level, it does mean that cooler dense air does equal more power. (There is a lot I do not know about this claim from Banks, but I'm talking very generally here.)

I had some fun learning about all this with my VW Golf when I upgraded the turbo to a larger more efficient one. I have a tuning device, and to start, I kept the same 16 PSI tune I was running with the smaller turbo. Even when running the same max boost (same exact tune) with same intercooler and intake, the more efficient turbo added +20-25 HP. Cooler denser air, more oxygen, more power. The smaller turbo was getting out of it's efficiency range and generating a lot more heat than the larger turbo. The increased IAT's and EGT's would also cause the ECU to dump more fuel to cool things down...thus richening AFR and loosing more power. After I turned up to 21 PSI and compensated fueling (my current summer tune), there was a +60 HP difference from the smaller turbo that couldn't compress air as efficiently.

 

[Clint Rivera]

The fan included is a 16" SPAL fan. Charles said the CFM on it is the same as what the stock fan on the 4.0 pushes.

He said if you mount the heat exchanger underneath the vehicle tucked up into the frame, it doesn't overheat at all. So this has me thinking that the overheating is actually caused by so many things being packed in front of the radiator... a heat exchanger AND A/C condenser, as oppose to just the latter. He agrees with that as well.

So one path I could take is mounting the heat exchanger underneath the vehicle.

I had a 16" Spal fan on my first 5.3 swap. Completely stock engine, and it would run hot. I upgraded to a Lincoln MKVII fan and it stayed cool. Part of the reason was for the larger shroud which (which made the whole assembly deeper) and the rest was the massive amperage the thing drew. They draw 40 amps continuous, which is about half a horsepower.

 

[Chris]

I had a 16" Spal fan on my first 5.3 swap. Completely stock engine, and it would run hot. I upgraded to a Lincoln MKVII fan and it stayed cool. Part of the reason was for the larger shroud which (which made the whole assembly deeper) and the rest was the massive amperage the thing drew. They draw 40 amps continuous, which is about half a horsepower.

Wow, 40 amps from the Spal? Sheesh.

Is the Lincoln MKVII fan electric or belt driven?

I'll have to consider my options here. A stock fan won't work period, simply because of the crank driven supercharger pulley. So I'm stuck with an electric fan. At that point, the thing to pay attention to (in my mind) is heat exchanger placement, radiator size, and fan shroud. I could be way off, but I think those are the factors at play here.

 

[Clint Rivera]

Wow, 40 amps from the Spal? Sheesh.

Is the Lincoln MKVII fan electric or belt driven?

I'll have to consider my options here. A stock fan won't work period, simply because of the crank driven supercharger pulley. So I'm stuck with an electric fan. At that point, the thing to pay attention to (in my mind) is heat exchanger placement, radiator size, and fan shroud. I could be way off, but I think those are the factors at play here.

40 amps from the Lincoln fan. The Spal was less than 30 I think. The MKVII fan is electric with an integrated shroud.

If you can put the heat exchanger somewhere besides in front of the radiator, you'll probably be fine for most situations outside of climbing sand hills in boost on a hot day with the A/C on or if your radiator is packed with mud. Slow crawling (low rpm) is where the electric fan could have an advantage.

I would imaging the supercharger is going to be used mostly on the road, and if you're in boost for sustained time, you're going to be going fast enough airflow though the radiator should be sufficient.

All that said, I'm not sure what is the best upgrade TJ 4.0 radiator?

 

[Chris]

40 amps from the Lincoln fan. The Spal was less than 30 I think. The MKVII fan is electric with an integrated shroud.

If you can put the heat exchanger somewhere besides in front of the radiator, you'll probably be fine for most situations outside of climbing sand hills in boost on a hot day with the A/C on or if your radiator is packed with mud. Slow crawling (low rpm) is where the electric fan could have an advantage.

I would imaging the supercharger is going to be used mostly on the road, and if you're in boost for sustained time, you're going to be going fast enough airflow though the radiator should be sufficient.

All that said, I'm not sure what is the best upgrade TJ 4.0 radiator?

Yes, you're right about that. It's not like I would even be seeing any boost when I'm off-road. The only places I'd really be in boost are around town or the highway probably.

Charles seems to think really highly of Griffin, and @Rescue6 seems to like his as well. They're made in the USA from what I read on their website, and they do all sorts of custom applications. I have weeks to decide on something, so I'll keep looking.

I could mount the heat exchanger under the vehicle, that's something I'm still toying with if I can find the right place for it.

 

[jtf440]

@Chris Maybe you could do something along these lines:
https://www.stu-offroad.com//engine/transcooler/transcool-1.htm
EDIT: Sorry wrong link, this is the one I was thinking of:
https://wranglertjforum.com/threads...-transmission-cooler-on-your-wrangler-tj.590/

 

[Chris]

@Chris Maybe you could do something along these lines:
https://www.stu-offroad.com//engine/transcooler/transcool-1.htm
EDIT: Sorry wrong link

This is an option. Though I would have to get a much differently shaped heat exchanger, as the one it comes with is nowhere near that compact.

 

[jtf440]

This is an option. Though I would have to get a much differently shaped heat exchanger, as the one it comes with is nowhere near that compact.

I just updated with the correct link.

 

[Chris]

I just updated with the correct link.

Oh yeah, I am toying with this idea for sure!

 

[jtf440]

Oh yeah, I am toying with this idea for sure!

I do too much reading with these jeeps that I immediately knew a way to get the cooler off the front, but I couldn't remember where I saw it lol.

 

[Chris]

I do too much reading with these jeeps that I immediately knew a way to get the cooler off the front, but I couldn't remember where I saw it lol.

I’ve actually got that same DeRale cooler on mine, but it’s for the transmission obviously.

 

[Squirrel Trap]

With respect to those who believe 100% in the stock radiator. No the stock radiator is not superior to a high quality radiator and electric fan setup. I've ran both and would NEVER go back to the crap stock plastic bs cheaply made junk that comes stock. They are garbage and no the OEM is not any different than the chinese made ones. Plastic mated to metal, absolute crap, am I saying they can't last, no, do they sometimes, you're completly full of shit if you say they are quality. Where do you think MOPAR is getting them, they aren't made here. They are the same garbage period. Are there badly made aluminum radiators, yes. Are there high quality ones that are inexpensive, YES! Go to ebay, search performance cooling or ozcooling products. Well made kits that work, way better than stock and for the money amazing. Could you get a bad product, maybe but the customer service is good enough and you can get a 1yr warranty through square that covers everything and labor 100%. Close to 5000 positive ratings for performance cooling products.
My experience: 3 stock radiators in 10 years and I finally decided to go aluminum with an electric fan. Higher capacity in fluid, more engine bay room, less rotating mass in that no fan or clutch. Again tons of experts on here and fine, I'll respect your opinion but you're wrong. It's called physics and although I'm not dynoing anything and trail use vs highway use are two different animals, there is parasitic power loss in the use of a fan clutch and fan vs electric. Heat transfer is better and combined with the added fluid capacity, electric fan and heat transfer my engine maintains a more stable temperature by leaps and bounds especially on the trail when you need it most going 6 miles in 4 hours. Engine runs smoother, power is smoother and quicker off the pedal but not by leaps and bounds. Power gain on my 4cyl, yes! how much, probably not more than a few but by percentage on a 4cyl, 37" tires, long arm suspension, G2 dana44 front and 8.8 rear axles 4.88 with ARB's. Ax15 and an Atlas 4sp...significant enough to notice especially going up inclines on the hwy etc. Around town and on the trail, insignificant outside of runs smoother, better pedal and cooling much more consistent.

 

[Jerry Bransford]

With respect to those who believe 100% in the stock radiator. No the stock radiator is not superior to a high quality radiator and electric fan setup.

You'll get a LOT of pushback on those of us who know better. The TJ's OE Mopar coupled with the serpentine belt-driven fan is preferred by us desert wheelers who often wheel in very hot conditions. If an aftermarket radiator coupled with an electric fan worked better, it'd be a common conversion for those of us wheeling in hot conditions. Heaven knows we modify most of the other parts of our Jeeps but the factory cooling system is MORE than up to anything the hottest conditions can throw at it. And if there's a most common problem I see in the desert causing overheating, it's from having converted the 2.5 or 4.0 engine to an electric fan.

 

[Squirrel Trap]

You'll get a LOT of pushback on those of us who know better. The TJ's OE Mopar coupled with the serpentine belt-driven fan is preferred by us desert wheelers who often wheel in very hot conditions. If an aftermarket radiator coupled with an electric fan worked better, it'd be a common conversion for those of us wheeling in hot conditions. Heaven knows we modify most of the other parts of our Jeeps but the factory cooling system is MORE than up to anything the hottest conditions can throw at it. And if there's a most common problem I see in the desert causing overheating, it's from having converted the 2.5 or 4.0 engine to an electric fan.

There are also a LOT of guys setting them up incorrectly. I've spent plenty of years in the Arizona heat, Colorado high elevation and now live in the Pacific Northwest. The main part of my post isn't to say I'm right in ALL instances outside of the stock radiators are garbage. As far as SoCal and the area you are referring to IDK, maybe you have the one instance of a geographical area that is outside of the greater percentage of the rest of us. Jerry your advice is usually pretty strong and I have representations of your advice on my Jeep btw. There are applications where a mechanical fan would work great, steel better than aluminum etc. I am using a 3 way switch on my fan for on, off and auto temp control via the sensor, npt, don't use a probe in the radiator fins btw. Full shroud and 16" fan. Obviously the volume of air pulled by the fan is key so buy the correct fan. The radiator I'm using is 3 row but there are 1 and 2 row radiators available that I would probably not recommend.

 

[jjvw]

My OEM radiator survived 120k miles. That is exactly why I replaced it with another OEM radiator. If I'm around when this one fails, I'll report back. But it might be another 10 years.

In the mean time, with my shitty OEM replacement radiator (and water pump) I can report that typical engine temps are consistently in the low 200's according to the ODBII after another 15k miles.