Ferrari Mailing List: Twin-Turbocharged 1983 Ferrari 308 GTS Quattrovalvole for sale on BaT Auctions - ending December 22 (Lot #62, 108) | Bring a Trailer

[Douglas Anderson (dnt]

Under piston oil cooling? – cool idea for a hot piston.

In 1970, Porsche did it with their 2.2 mag case flat six’s.

 

But wait – there’s more.  By the mid 1980’s Porsche develops their F1 TAG Turbo engine for McLaren.

1500 cc – twin turbo, 1,100 bhp at about 12,500 rpm.

Oil squirters for this engine too?  You bet, but, uh, a bit different.

Each piston had a circumferential trough end milled into the piston from the top. 

Then a donut ring plug was electron beam welded to close trough top.

If you look closely at the piston top two concentric grey weld rings are barely visible.

 

Two holes in the bottom of the piston. 

When the piston dropped to BDC one hole covered squinter that filled the piston with oil and the other hole exhausted the hot oil.

Preserved the rings.

Top secret.

 

Cheers

Doug

Attachment: TAG Piston 1.jpg
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Attachment: TAG Piston - under.JPG
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