Lower MFI Heat Exchanger Hose

Jandrews · 09-19-2006, 07:41 PM

After reading through john cramer's unfortunate circumstances, it got me thinking. Can someone post a picture of the CORRECT lower MFI heat exchanger hose? I ordered new ones from Pelican, but my upper and lower are the same, double-layered paper ones. Is the lower one supposed to be something different? Is a heater hose of the correct diameter a suitable replacement? What is the best?

Thanks,

JA

Zeke · 09-19-2006, 07:55 PM

The lower hose is a very thick affair. I figure that's to withstand the elements below the engine tin. I my mind the paper will not carry the heat as well all the way from the front of the HE.

sballard · 09-20-2006, 04:38 AM

I was having trouble locating this hose about a year an a half ago (before I found the forum). Stoddard first sent me the outer hose that fits directly to the thermostat and then on exchange, sent me a correct diameter hose that fits the heat exchanger and sheet metal connector properly but it is made out of the thin material similar to the hoses that connect the heat exchanger to the flapper boxes. The thermostat now gets hot to the touch and the engine seems to lean out with warmup, but I've often worried that it is not the thick rubber hose that is apparently the correct OE. Could someone give me the correct part# for this hose?

Steve B.
1972 911T

Jandrews · 09-20-2006, 02:02 PM

That's what I thought, Milt, and I agree with your assessment of the paper product for heat transfer.

Anyone have a picture of:

1) The "official" proper hose to be used for this purpose, or
2) A suitable, durable substitute that will perform as good or better than the official part?

Thanks,

JA

304065 · 09-20-2006, 02:33 PM

Pelican sells a replacement hose. It may not be exactly the same as the original, but "Vaporcord" is a German-made hose that appears to be identical. I'll let you know when I get it.

MFI Rubber Hose

Jandrews · 09-20-2006, 03:14 PM

Is it this one?

What confused me is that this says "for injection pump".

JA

eapcpa · 08:10 AM

That is not original but if it's a heavy rubber hose it should work fine and stand up to the elements under the car.

Grady Clay · 09-23-2006, 04:38 PM

Porsche put some thought into the thermostat system. One of the parameters is the rate of heating of the air hoses to the thermostat. Changing the type of hose changes the heat-up characteristic of the thermostat.

The best place to start is stock. Most changes involve getting the thermostat to turn off sooner. This can be done with an aluminum hose inside the stock rubber hose. There is a VW hose that can fit over the double concentric hoses from the tin to the thermostat.

Big issues are that there aren’t any air leaks at the heat exchanger or hose to the heater control box.

Best,
Grady