Back in the 70's and 80's I worked with Holbay Engineering in the UK at Martlesham near Ipswich.
They did all my machining work.

John and the crew built Hillman Hunter and Rapier engines and Lotus 7 motors...just to give you an idea of his expertize.

His full race motors where Anglia BDA and OHC Ford Pinto 2.0. He said that on the dyno, the Pinto motor produced most HP at 60C coolant temperature. Hotter or cooler lost power. He said something about the intake valves being too big, volumetric efficiency, blah blah blah....

Anyway...he used a restrictor in place of the thermostat because removing the 'stat caused localized overheating in the cylinder head. He had a bunch of them made so just popped one in for the dyno session. Apparently there where no 60C 'stats available.

He showed me a twin cam head he developed for Lotus..( Cosworth stole some of his stuff.). but the real business was the BDA on the dyno at 10,000 rpm....on the other hand he bought Cosworth stuff and put Holbay on it ! Now, the Chinese do that ! Wonder if they got that idea from John ?


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[http://languageandgrammar.com/2008/01/14/youve-got-problems-not-issues/ ]

"A liberal is someone who feels they owe a great debt to their fellow man, which debt he proposes to pay off with your money."

I removed the stat. It did not seem to help at all.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Tom,
Just a note on cooling--not related to your problem.
Too much cooling increases engine wear. I have a chart ( somewhere) produced by FoMoCo that shows engine wear versus temp. Below a certain temp the curve shows significant wear, but above that critical temp, wear nears ceases. It stuck in my mind because it seems so counter-intuitive.

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1982 300SD " Wotan" ..On the road as of Jan 8, 2007 with Historic Tags

yep.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.