Radiator questions

[BeefaRu]

Greetings from a new guy.

 

I found a home for people with cars like mine! Cool.

 

I have an AC/radiator/fan issue I need some advice on. I'll try to be brief.

 

My 88 wagon has a 2.2 legacy in it. I originally had a single core GL radiator with dual GL lower profile fans (not sure which year). With AC on I did OK in traffic, but built up too much heat on 90-95º days at 55-70 mph going up even slight inclines. I'm curious about the CFM's that those older fans pulled because my current situation is even worse.

 

With a new loyale 2 row radiator, I now have only 2 inches between radiator core and engine & the fans I had don't fit. I've put in Spal's thinnest 2" clearance fans, but they don't pull enough CFM's through the thicker radiator in stop/go traffic with AC (on a hot day). Performance under a load NON-AC up medium incline 40-55mph turns into a dangerously hot thing within about 10-15 minutes because LESS air moves through the thicker radiator.

 

It seems my only choice is to go back the original single core with two subaru fans. But I already know that won't work on a 95º day with AC on pulling even slight inclines at 55-70.

 

Basically I've come to the conclusion I need much higher CFM fans (2000 CFM total or more) and a radiator/fin design that lets more air through on the highway, but still has enough density and/or thickness to cool in stop/go traffic with decent fans.

 

Griffin radiator makes an aluminum 1.25" single core that can be made with a special low fin height/ more tubes design that gets me 20% more efficiency than the original stock copper/brass (at a high cost).

They can also go to 1.5" or go dual core with with either thickness without the low fin/more tubes design at about $450.

 

Other options I've tossed around are:

A fan shroud (but those block highway airflow)

Pusher fan on the front (no room in front of condensor and AC tubes get in the way too -- plus pusher fans are in the way of highway airflow)

Getting the hood vent & scoop from an 81 280z. I heard some hood ventilation can help, but I don't know if the physics of the idea stands up in both stop/go and highway.

 

And last but not least: Moving the whole condensor/radiator rig forward. More air in front of the engine, more space for much higher CFM fans, and space for an aluminum 2 core -- Has anyone here done that?

 

I'll stop babbling for now. Would appreciate any insights/ideas. Thanks! --E

[MorganM]

First off quit over heating that poor thing!

 

I"d try some high CFM push fans first.

 

That tricked out radiator with good push fans would prolly set you up nice.

[archemitis]

i put a cowl induction hood scoop on mine for that very reason. it made a big diference, in stop and go, and cruisin down the highway.

 

get the old z scoop put a small heater core underneath it, with a computer fan on it. plumb it in after your heater, so you still have hot heat.

or an oil cooler.

but first make sure there are no leaks. a bad radiator cap can make you overheat on the highway.

 

did you mean you had a 2.2 engine swaped in, or a legacy 2.2 radiator in there?

[BeefaRu]

First off quit over heating that poor thing! I"d try some high CFM push fans first.

That tricked out radiator with good push fans would prolly set you up nice.

I had an accurate temp sensor put in instead the digital I had. The worst I've seen it at is 230 for a minute or two.

As far as push fans...no clue where there's room. I can take a pic if you want.

get the old z scoop put a small heater core underneath it, with a computer fan on it. plumb it in after your heater, so you still have hot heat.

or an oil cooler.

but first make sure there are no leaks. a bad radiator cap can make you overheat on the highway.

 

did you mean you had a 2.2 engine swaped in, or a legacy 2.2 radiator in there?

The engine is 2.2 the radiator is GL. I don't know where there's room for a heater core & a fan. Here's a couple shots where you can see the clearance, and the limited space.

 

[Skip]

Beef,

Sweet job on the transformation, which tranny did you use?

 

On the over heat - I have long been contending that the surfboard bumper may

be a contributing factor.

 

The flow of air over the bumper top lip may

cause a "tumble home" effect.

This turbulence slows the flow through the core at speeds.

 

I have noticed this on every turbo car I've driven (including one with a brand new twin row rad)

 

I have removed the grill to see if that may have been the cause -it wasn't.

 

I came to the conclusion that more air needed forced into the core.

 

The place for this air was below the bumper.

 

I added an RX front spoiler, the results were quite satisfying,

both H20 and oil temps dropped by 20 deg F at highway speeds

 

By the way I have only the factory electric AC fan with shroud - no viscous clutch mechanical.

 

(I run a lab style Fluke digital thermometer with type J thermocouples.

This is powered by a small inverter with probes in the coolant system and oil pan)

 

Good luck, please keep us informed of your progress.

[BeefaRu]

Beef,

Sweet job on the transformation, which tranny did you use?

Thanks, but I take no credit for the work. The guy that did it was very capable though. An 87 rx dual range with 4:11 legacy LSD was what ended up going in the car.

I have removed the grill to see if that may have been the cause -it wasn't....I added an RX front spoiler, the results were quite satisfying,

both H20 and oil temps dropped by 20 deg F at highway speeds.

That could be an excellent highway solution! How does the RX spoiler mate up with the GL front end? Do you have any pix? --E

[Skip]

Yikes, a RX 10 speed tranny has a 3.7 FDR (Front Diff. Ratio)

You have a 4.11 rear diff?

What no front axles and the diff lock on all the time?

 

My saints, that thing must scoot!!

 

The RX front spoiler is a bolt on

(once you remove the other lower lip).

 

Here is a picture of Willy, Kinda hard to see the spoiler but it's there.

 

[BeefaRu]

Yikes, a RX 10 speed tranny has a 3.7 FDR (Front Diff. Ratio)

You have a 4.11 rear diff?

What no front axles and the diff lock on all the time?...

From what I understand the RX tranny is modded to match up with the rear diff, and the car is full time 4WD just like a legacy. That drops the tranny down for lower close ratio gearing which is good for several things. To get 5th gear higher I had a 5th sprocket from a forester put in which gets me about 3k rpm @ 75mph where it used to be 3k @ around 60 with the stock RX 5th dropped to 4:11

The RX front spoiler is a bolt on

Thats brilliant. I'll pick one up & get it painted. I'm amazed that just the spoiler made so much difference. I may have never learned that if you didn't chime in. Thanks Skip! --E

[BeefaRu]

Further research insights:

 

I learned having any significant gap between condenser and core is not good. Closing that gap with a "shroud" is supposed to help create a better air channel and help make my wimpy puller fan rig more effective. Makes sense to me.

 

Will locate an RX spoiler/dam and mount it, check it, then get it painted.

 

I'll also be mounting a second fan. I could only squeeze in a 9" because of the power steering pulley bolt. That gives me a total of 1500 CFM but thats 500 short of a minimum recommended by one radiator manufacturer. --E

[Skip]

E,

By chance have you tried Guinness in a bottle?

 

All seriousness aside.

I like the idea of the coupling of the cond. and the rad.

 

Being into temps and the control there of..

Have you given thought to putting a partition

in to sequester your intake.

 

The opening in the inner fender will have it

into breathing cooler air?

 

The way it is now it looks like you are ingesting hot air from the rad.

 

My intake is run into the inner fender for this reason..

[BeefaRu]

E, Have you given thought to putting a partition

in to sequester your intake.

Yes I would like to do that. Haven't gotten around to having someone help me with it, but my landlord could. He's put out a few cool things from his body/paint garage.

[NorthWet]

First things first...

 

QUIT USING ALUMINUM!!!

 

Copper has approx twice the heat transfer rate as does aluminum (or if you want to turn it around, aluminum has twice the resistance to thermal flow as does copper). Factor in density and its effects, and copper works even better. Copper also does not form a thermally insulative "skin" over time as does aluminum.

 

Go to your local neighborhood private radiator shop and see about having a custom radiator built: Staggered row, straight fins (and of course it will be copper/brass). This style radiator will provide more rows in less thickness, the tubes peirce the fin plates so that they contact the complete circumference of the tubes instead of just part of the side, and the fins themselves are thicker and better louvered than standard radiators. This is the style that these shopes build for race cars, and the cost should be around $300 (more or less depending on your local cost of living).

 

Best radiator money can buy... unless you go silver, or diamond processing gets better.

 

Cpt. Copper

[BeefaRu]

QUIT USING ALUMINUM!!!

Go to your local neighborhood private radiator shop and see about having a custom radiator built: Staggered row, straight fins (and of course it will be copper/brass).Cpt. Copper

Thanks for the info! I'm NOT using aluminum so far but have been researching it. COuple questions on your suggestions:

How many fins per inch? I need less fin density for my 950 & 550 CFM fans to pull their meager amount of air through. As I said, there's more radiator thickness and density than they can pull decent air through. Also, what is a good fin height to get more rows in without making the tubes too small? --E

[BeefaRu]

I apologize for blabbing all over my own thread. Someone said check in as I make progress.

 

These are my conclusions so far & what I think I'll do:

 

1. A 20% improvement is not worth the $ for a custom built Alum radiator. That's a last resort if everything below doesn't turn the tide on heat running AC.

2. Since the experts all concur that its a tossup between Alum. & Brass/Copper I'll stick with the new 2core B/C I have right now.

3. I'll close the gap between condenser & radiator making an air tunnel for better pull through from the fans, & get all condenser fins cleaned out.

4. I'll mount my second low profile fan for a wimpy total 1500 CFM

5. I'll pick up an RX front air dam per Skips suggestion

6. I'll buy the 81 280z hood I found with the heat vent and turbo vent/scoops. They're going in only if the other stuff doesn't work

7. I'll locate the scoop in the best location for a heater core add on and perhaps try that before going full on with a custom radiator.

8 If everything else doesn't work, I'll try the custom radiator, and if I need more room the last resort is to cut and move the radiator forward. But I'm pretty sure I'll never have to do that. Probably won't have to get the custom radiator either. But its good to have a plan.

 

Thats what I've come up with so far. Thanks for the input! Of course any other ideas are welcome! --E