Thermostat with cool tin and 1 5/8 merged exhaust

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Yes.

With a blower-cooled air cooled engine the cooling-air outlet is as important as the inlet since the pressure of the outlet plenum as seen by the cooling air largely determines the distribution or balance of the cooling air. Running without the lower tin-ware not only exposes the push-rods to hazards they were not designed to face, the air pressure under the vehicle -- a product of your forward speed -- can screw-up not only the function of the thermostat but the distribution of cooling air down thru the fins of the heads.

-Bob Hoover

You're on the right track. The thermostat has to be surrounded by sheetmetal etc. and in direct hot air flow. Else you will cook the engine. The draft from air passing from under the car when driving will cool off a thermostat that isn't "boxed in" like that.

Jan

Cool Tin ain't.

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It is when properly installed. See the Type IV. Or the Corvair. Or a Lycoming or Continental installed in a helicopter (ie, blower-cooling).

The after-market stuff is notorious for being blown out of position, causing it to perform even worse than the original deflector plates. Proper installation involves adding local re-enforcement to the center and welding attachment plates to the ends.

-Bob Hoover

We were talking about a T1

I don't know why so many people skip over these parts. Not only are they necessary for the thermostat and cooling, but they also direct the hot air flow straight back, away from the engine.

Finding the lower tin isn't hard. A few of the mail-order places carry it.

As far as block-off plates to fill in where the heater boxes were, Gene Berg was the only place. They used to sell OEM versions intended for stationary engines but then made their own for a while. I bought a set from them - a little pricey but worth it.

VWB126-119-461 which has been replaced by their GB 7400R and VWB126-119-462 which has been replaced by their GB 7400L.

?products_id=1263

RT

this compromise the proper functioning of the

So to sumarise what Bob, Jan and Raym If you intend using cool tins which cup the undersides of the cylinders, then

1. They must be properly mounted so they don't bend away from the cylinders and spill air...additional mounting will probably be required. An additional point here is that you must also leave the under-head small flat deflector plates in place - only the under-cylinder flat plate deflectors are removed when fitting cool tins.
2. You must leave the original underside plenum pieces in place which turn the used cooling air out the back of the car. This will ensure that the thermostat continues to see only the hot used cooling air and not have it mixed with other air under the car. It will also ensure that the turbulent high pressure air which exists under any car will not disturb the smooth flow of cooling air through the finning. If you have fitted an exhaust system which leaves the outer ends of the plenums exposed then these areas need to be closed off - the heater boxes provide this function with the stock exhaust system.

Regards Rob Rob and Dave's aircooled VW pages Repairs and maintenance for the home mechanic

Wow guys.... what a wealth of information.... Thanks a lot! So it looks the hot setup is to lose the cool tin, get the stock underside sheet metal along with the Gene Berg side pieces to replicate the hot air flow function of the heater boxes when using the J-tube style merged headers.... Thanks again! ......Larry H

How about just holding the cool tin against the cylinders by encircling it with wire -- the stranded kind used to hang picture frames. The wire goes under the cool tin and on top of the cylinders; the two ends are twisted together. That's what I did after seeing the tip in a Hot VWs article.

Randall

That's what I'll be doing when my "Kool Tin" arrives in the mail. I'll be using solid core steel wire about 8 awg or so. solid core should stay in place given a few turns onto itself from a pair of pliers.

Larry,

You can keep the "Kool tin". Just use it with the underside tin, too.

Here's a tip.

Use a 1/16" drill and make two tiny holes in the deflector, one on each side of the stud above. Then you can wire the plate right to the stud neatly.

RT