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Reply to "New exhaust to cure a hot-running engine"

WOLFGANG posted:

You need to post some pictures of your engine - top and bottom.  There may be an easily spotted issue - missing engine tin, unplugged heater tubes, missing air seals around the plugs, no Hoover bit, missing deflectors around cylinders, exhaust gases free to enter engine, missing tin/air leaks around dog house cooler (bottom piece is often missing), aftermarket shroud with no internal vanes, chrome cooling tins, etc.

Most VS engine bays I've seen have a round ~5" air inlet in the firewall (behind fan intake to right a couple inches) covered with a mesh screen - does your have it?  Note - VS in photo also has rubber seal completely around the engine lid - great for keeping rain water AND extra needed air out. Other have made a prop that keeps engine lid open a couple inches when driving to let in extra air.

Late 1975+ FI bugs and 356 Porsches (first used on the 4 cam 550 engine) added something called a Venturi ring to smooth/increase air flow into the engine cooling fan/shroud.  From AirCooled net -

Venturi Ring for Fan Shroud (Fan Inlet Velocity Stack), Black Powder Coated, All Doghouse Fan Shrouds
Venturi Ring for Fan Shroud [Fan Inlet Velocity Stack), Black Powder Coated, All Doghouse Fan Shrouds

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Venturi Ring for Fan Shroud, Stainless Steel Black Powder Coated, All Doghouse Fan Shrouds significantly improves airflow and cooling by reducing turbulence of air entering the fan. All stainless steel construction, with spot welded mounting tabs for an EZ install. Increase your cooling air by 10% with no other changes! The venturi shaped ring smooths air entry into the fan, and less turbulence means more airflow and better cooling! VW added these to the FI fan shrouds, since those engines had such a tough time keeping cool, and now these are available for you to add to your doghouse fan shroud! These operate on the same principle that a Velocity Stack does to increase airflow into a carburetor!

This can be either riveted or welded to the fan shroud, using the included mounting tabs.

Price: $59.95 

@WOLFGANG Thanks for the advice.  I will snap some photos when it stops raining.  That said, I actually believe the photo you used IS my engine bay (before I painted the air cleaner covers Porsche aluminum, and added the yellow valve clearance decal on my fan shroud) .  I'll have to check it out and compare....but I haven't found too many speedsters that have my Irish Green color--only have come across one other.