[Gooserider]

Winewood was the only one who addressed my rattle question so far, he seems to think it isn't a big deal.

I sort of agree, if I could be sure the rattling bits would stay in the core. But I'm afraid that if they managed to get into the blocks they might stop something up, or possibly damage the pump if they made it that far.

A high volume flush might get them out if I combine it with a good shaking at the same time.

As to cutting the tubes, it's pretty essential on this core...

The 2-342 is about as close to the ideal WC rad as you get according to Cathar and some of the other technical experts. In one of the discussions, he described the ideal rad as having one pass, a 2 layer, 1.3" thick core, with lots of frontal area and ~16 fins/inch of brazed on folded fins.

The 2-342 is 9.5" X 6.125" X 2" thick. I think it's 2 layer, but it might be 3 (hard to tell without cutting it open...) The fins are folded and brazed, I didn't measure the fin/inch count, but it looks like around 16/inch plus or minus a bit, I know you can see through it if the angle is right. Most important, it is a SINGLE PASS core.

How important is a single pass? According to the spreadsheet developed by the folks in the simulator area, VERY important. The 2-274 dual pass core is 0.3" longer, but otherwise identical. The dual pass 2-274 has FOUR TIMES the flow resistance of the single pass 2-342!

This makes some sense actually. All cores of a given width will have about the same number of tubes, regardless of whether the core is single or double pass. In a single pass rad, the coolant flows in parallel through ALL the tubes; but in a dual pass, the coolant flows through just half the tubes in each direction. You could almost think of it as a single pass with half the thickness and twice the length. Remember that two of the most important factors in flow resistance are cross sectional area and length... A dual pass is worse both ways.

The problem with the 2-342 is that the I/O pipes are really strange and long, they come out of the tanks and one goes sort of up and out, while the second comes out, runs across the face of the core, then angles off to parallel the first. If you look at the picture in the heatercore database it's bad enough, reality is even worse. I would guess that the box for the core is 3-4 times as large as the core itself because of the pipes! It might be possible to get the rad into a case, but one wouldn't have room for anything else unless you cut the tubes.

BTW, I went through the entire photo collection on Leaky-car.com, and made a list of all the single pass rads (assuming a dual pass has the I/O pipes on the same end, and a single has them on opposite ends) . There are only about 22 of them, which makes them fairly rare. Most of these have I/O's that come out the sides or top and bottoms of the tanks rather than the face, which makes mounting a bit more of a challenge and need more room for plumbing hookups. The 2-342 is about the largest with I/O's on the tank faces.

So I guess I'll have to cut the pipes and solder some kind of fittings onto the ends....

Gooserider