The Ford Barn

Richard Lorenz · 08-02-2018, 07:35 AM

Does anyone know what compression pressure to expect with a Model B 4-cylinder engine?

Mike V. Florida · 08-02-2018, 09:17 AM

100 lbs.

ursus · 08-02-2018, 10:08 AM

The Model-B has only a 4.6 compression ratio, which is slightly higher than the Model A. Mine was never higher than 75-80 pounds, with an 0.060 overbore.

emf · 08-02-2018, 11:48 AM

I have not checked my Model B in the roadster, but my Model A engine with a 5.5 Snyder head gets 95 lbs on all four...

Frank

Bob Bidonde · 08-02-2018, 12:37 PM

Ballpark is 14.7 x 4.6 = 67.6 psig. Dynamic head from piston motion will make the pressure higher, so psig of 70 or more seems reasonable.

larry loyd · 08-03-2018, 06:59 AM

Sponsored Links (Register now to hide all advertisements)

Mine is around 75 psi on all four. It is a 39 diamond block in great running condition.

08-02-2018, 07:35 AM	#1
Richard Lorenz Senior Member Join Date: May 2010 Posts: 447	Compression pressure Model B Ford Does anyone know what compression pressure to expect with a Model B 4-cylinder engine?

08-02-2018, 09:17 AM	#2
Mike V. Florida Senior Member Join Date: May 2010 Location: South Florida Posts: 14,054	Re: Compression pressure Model B Ford 100 lbs. __________________ What's right about America is that although we have a mess of problems, we have great capacity - intellect and resources - to do some thing about them. - Henry Ford II

08-02-2018, 10:08 AM	#3
ursus Senior Member Join Date: May 2010 Location: Oregon Posts: 1,375	Re: Compression pressure Model B Ford The Model-B has only a 4.6 compression ratio, which is slightly higher than the Model A. Mine was never higher than 75-80 pounds, with an 0.060 overbore.

08-02-2018, 11:48 AM	#4
emf Senior Member Join Date: Mar 2013 Location: Hudson, NY Posts: 511	Re: Compression pressure Model B Ford I have not checked my Model B in the roadster, but my Model A engine with a 5.5 Snyder head gets 95 lbs on all four... Frank

08-02-2018, 12:37 PM	#5
Bob Bidonde Senior Member Join Date: May 2010 Location: Long Island, NY Posts: 3,466	Re: Compression pressure Model B Ford Ballpark is 14.7 x 4.6 = 67.6 psig. Dynamic head from piston motion will make the pressure higher, so psig of 70 or more seems reasonable. __________________ Bob Bidonde

08-03-2018, 06:59 AM	#6
larry loyd Junior Member Join Date: Jan 2018 Location: Spring Hill, Florida Posts: 1	Re: Compression pressure Model B Ford Sponsored Links (Register now to hide all advertisements) Mine is around 75 psi on all four. It is a 39 diamond block in great running condition.