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Huskymaniac
01-11-2011, 08:52 PM
After doing some reading, it became apparent that this foam is not just a minor afterthought of the original engineers. The foam serves its strongest function while idling or driving slowly. Without it, the fans will suck in hot engine cabin air through the gap and then through the radiator. It can make a big difference in operating temperature. At speed the effect is less but the foam does stop cold air from bypassing the radiator after it has been brought in through the grill and condenser. It probably has a minor impact on operating temperature.

I am considering this for replacing my old deteriorating foam:

http://www.mcmaster.com/#catalog/116/3535/=ajvciw

I was thinking of part number 8865K52 and then cutting out strips from the sheet. It is high temperature foam with a high temperature adhesive.

Manarius
01-11-2011, 09:13 PM
The foam is an after thought. A crack of that size could never flow enough hot air that it could cause a hike in temperature. In fact, I'd argue that after I removed that foam, my temperature needle actually sits lower than it did with the foam.

If blocking that area was so important, why didn't the engineers put a piece of plastic there? Surely it must be cheaper than high-temp foam and would do an even better job!

Huskymaniac
01-11-2011, 09:30 PM
The foam is an after thought. A crack of that size could never flow enough hot air that it could cause a hike in temperature. In fact, I'd argue that after I removed that foam, my temperature needle actually sits lower than it did with the foam.

If blocking that area was so important, why didn't the engineers put a piece of plastic there? Surely it must be cheaper than high-temp foam and would do an even better job!

I haven't done a before and after on this car but I have seen data on other cars, including a Vette, and it does make a big difference in the idle temperature of the car. At least on those cars it did......

North Ursalia
01-11-2011, 09:51 PM
A piece of squishy foam seals better (when new) than a piece of plastic or metal would. Radiator blocking plates are fairly popular aftermarket add-ons- ZeroSports and Siebon make them, amongst others, for Subarus.

michael
01-12-2011, 06:26 PM
I haven't done a before and after on this car but I have seen data on other cars, including a Vette, and it does make a big difference in the idle temperature of the car. At least on those cars it did......

My 84 rabbit had a piece of cardboard there from the factory and it did make a difference without it. I replaced the foam in the SVX last year with some stuff from Lowe's. I know what you're thinking, but it is a good match to original. Make sure you get the 1" x .5" one and run the .5" vertically. The 1" part will squish to fit. While you're at it, check the condition of the foam on the sides of the radiator.

oab_au
01-12-2011, 06:38 PM
My 84 rabbit had a piece of cardboard there from the factory and it did make a difference without it. I replaced the foam in the SVX last year with some stuff from Lowe's. I know what you're thinking, but it is a good match to original. Make sure you get the 1" x .5" one and run the .5" vertically. The 1" part will squish to fit. While you're at it, check the condition of the foam on the sides of the radiator.

There is also a piece between the bottom of the radiator and the condenser.

This is to prevent air getting into the engine compartment, drawing it only through the radiator. They went to a bit of work to ensure that the low pressure caused by the flow under the car, produced the best flow through the coolers, when moving fast.

Harvey.

Huskymaniac
01-14-2011, 01:10 PM
My 84 rabbit had a piece of cardboard there from the factory and it did make a difference without it. I replaced the foam in the SVX last year with some stuff from Lowe's. I know what you're thinking, but it is a good match to original. Make sure you get the 1" x .5" one and run the .5" vertically. The 1" part will squish to fit. While you're at it, check the condition of the foam on the sides of the radiator.

I looked at it today and there weren't pieces of foam on the sides. I'm not sure there even could be because the radiator is slightly wider than the condenser. There is a piece on the bottom, as Harvey said. That one seems to be in good enough shape to hold all the dead bugs and little pieces of leaves and crap.

Huskymaniac
01-14-2011, 07:40 PM
Can anyone else comment on whether they have foam on the sides? When I look at my car, I don't even think I can put foam on the sides as there are items crossing in between the radiator and the condenser and they come in from the sides. I think one is the cable for the hood latch and one is the power steering "cooler".

North Ursalia
01-14-2011, 07:47 PM
Checking on Subaruparts.com, I come up with "seal radiator side" in the attached image. Looks like there should be one- I'm going to check my '92 tomorrow when there's daylight.

Huskymaniac
01-14-2011, 08:22 PM
Checking on Subaruparts.com, I come up with "seal radiator side" in the attached image. Looks like there should be one- I'm going to check my '92 tomorrow when there's daylight.

It doesn't look like that part seals the gap between the radiator and the condenser. I will look for that tomorrow too.

kwren
01-14-2011, 08:29 PM
It doesn't look like that part seals the gap between the radiator and the condenser. I will look for that tomorrow too.

Great idea Tony, check it out and let us know!!!

Keith:cool:

North Ursalia
01-14-2011, 09:26 PM
If it wasn't 3 degrees out right now, I'd probably go check mine now :lol:!

kwren
01-14-2011, 11:16 PM
Checking on Subaruparts.com, I come up with "seal radiator side" in the attached image. Looks like there should be one- I'm going to check my '92 tomorrow when there's daylight.

This is the attached image...
http://www.subaruparts.com/diag/?model=2&year=1992&style=4WD&body=&scn=4&category=450-B

#15 is the side seal and there are 2 of those... one for each side.
#16 is the lower seal and there is one of those.
the top seal comes with the radiator and I don't think it can be ordered separately but it could be replaced as has been previously suggested with weatherstripping from a hardware store... Home depot or equivalent.

Keith:cool:

Huskymaniac
01-15-2011, 11:49 AM
If it wasn't 3 degrees out right now, I'd probably go check mine now :lol:!

We hit 3F too. I checked it out this morning. There "was" foam on the sides at one point. But, it wasn't between the radiator and the condenser. It was just the sides of the radiator. And it didn't fill the entire distance. It was only about half to 2/3rds up. The reason is that there are items which come in from the sides between the radiator and the condenser. Those pieces of foam don't seem to serve much of a purpose other than maybe keeping stuff off the sides of the radiator. I would say that the top and bottom foam pieces do much of the air isolation. However, air will sneak around the sides due to the incomplete filling of the gap between the condenser and radiator.

SVX33
01-15-2011, 02:00 PM
That piece of foam on the bottom can become a real problem if it is not removed periodically to clean the crap that collects there. It holds moisture which rots the power steering cooler loop. I replaced mine after removing the leaky loop with an oil cooler from a motorcycle but the fine dirt still gets in there and clogs the lower fins of the radiator. There was no foam on the sides so I added some to keep the big stuff out.

North Ursalia
01-15-2011, 04:39 PM
I checked it out this morning. There "was" foam on the sides at one point. But, it wasn't between the radiator and the condenser. It was just the sides of the radiator. And it didn't fill the entire distance. It was only about half to 2/3rds up.

I found much the same- surprising, since the radiator has been replaced, and one or more of the previous owners didn't care about fine details like undoing screws and being careful with the foam around the radiator :lol:.