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Gus Carlheim engines

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Post Sat Apr 04, 2020 5:48 am

Posts: 3
Newbie here on this forum with limited knowledge of Gus Carlheim and have seen the Koslow-45Brit +others thread and wanted to know if there is an official history or historian with definitive knowledge of GC, where he came from how he got started modifying then manufacturing his unique engines. One has ended up in a 1949 Cooper Mk IV FIII car (sorry) that I am researching. I believe it was fitted in the late 90s-early 2000s and is now needing some TLC to revive and run again. Am checking archives for previous history and more info. I have scoured the net finding conflicting info and lots of stories. Any assistance much appreciated.

Post Sun Apr 05, 2020 9:25 pm

Posts: 1350
Location: Ojo Caliente,NM,USA
Maybe these will help. Sure looks like a JAP.

Post Mon Apr 06, 2020 6:56 am

Posts: 3
Thanks Dusty Dave, yes those are the pics thanks for posting.
I just found this in The Bulletin June 2012 Morgan 3 Wheeler Club Ltd

p4 From the Editor Brian Clutterbuck:

"Chris Towner was over for the Opening Run and
reckoned the week was the wettest drought he had
ever experienced. He was also reminded, by the
picture of Mike Guess’s air cooled 60” JAP in the
April Bulletin, of an article he read in ‘Vintage
Oval Racing’ published in 2009. The article was
about Gus Carlheim from Stanford, Connecticut
who imported JAP engines for use in Midget
racing cars in 1939. He found that Harley 60 cu in
motors from 1936 to 1945 had a stronger bottom
end and the same stud spacing allowed him to use
JAP air cooled barrels and heads. His engines
were producing 100 bhp and still competing in the

I have seen the thread with Koslow and Brit45 where the former states:
"G C stands for Gus Carlheim ! He was a famous ( in midget race car circles anyway!) tuner of engines from the Bronx! He first started modifying JAP 8/80 engines and gradually ended up remaking just about the complete engine to a much more robust specification as parts of the JAP blew up."

Post Mon Apr 06, 2020 6:58 am

Posts: 3
I'm also trying to track down these various bikes that have GC engines:

like the old JAP : ... -bike.html

or the BTTW Justin Walls Petrali Carlheim project ... er_13.html

Post Mon Apr 06, 2020 2:28 pm

Posts: 21
Location: Santa Fe,NM
Dats some interestin info there, thanx!

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