Go Back   The Ford Barn > General Discussion > Model A (1928-31)

Sponsored Links (Register now to hide all advertisements)

Reply
 
Thread Tools Display Modes
Old 09-11-2018, 10:35 PM   #1
tjw
Senior Member
 
tjw's Avatar
 
Join Date: Jun 2011
Location: Australia
Posts: 229
Default Model A head combustion chamber shape

An old Model A alloy head I came across with an interesting combustion chamber design. Good, bad, otherwise, any one got any comments on its design / performance.
Attached Images
File Type: jpg P1130264.jpg (34.0 KB, 138 views)
File Type: jpg P1130265.jpg (59.2 KB, 128 views)
File Type: jpg P1130267.jpg (63.3 KB, 101 views)
File Type: jpg P1130266.jpg (60.2 KB, 99 views)
File Type: jpg P1130268.jpg (67.9 KB, 108 views)
File Type: jpg P1130269.jpg (91.6 KB, 95 views)
tjw is offline   Reply With Quote
Old 09-11-2018, 11:20 PM   #2
Kahuna
Senior Member
 
Kahuna's Avatar
 
Join Date: May 2010
Location: NorCal
Posts: 2,617
Default Re: Model A head combustion chamber shape

I like it a lot.
Who made it?
Looks like an excellent way to get some reasonable flow & a bit of compression
Kahuna is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 09-11-2018, 11:48 PM   #3
tjw
Senior Member
 
tjw's Avatar
 
Join Date: Jun 2011
Location: Australia
Posts: 229
Default Re: Model A head combustion chamber shape

I know very little about it other that it may have been made in Australia and by whom I do not know as there is no brand name on it.

Last edited by tjw; 09-13-2018 at 12:43 AM.
tjw is offline   Reply With Quote
Old 09-12-2018, 09:47 AM   #4
P.S.
Senior Member
 
Join Date: Jul 2012
Location: State of Jefferson
Posts: 1,483
Default Re: Model A head combustion chamber shape

Looks homebrew to me.

It's missing some water passages if it is for a Model A block.
P.S. is offline   Reply With Quote
Old 09-12-2018, 10:35 AM   #5
Kahuna
Senior Member
 
Kahuna's Avatar
 
Join Date: May 2010
Location: NorCal
Posts: 2,617
Default Re: Model A head combustion chamber shape

To me,it appears that someone knew what he was doing.
I'd fix whatever needs to be fixed & run that thing. I think
it would out-perform any other Model A/B flathead.
What's the other side look like?
Jim
Kahuna is offline   Reply With Quote
Old 09-12-2018, 10:57 AM   #6
Jim Brierley
Senior Member
 
Join Date: Jun 2010
Location: Temecula, CA
Posts: 2,801
Default Re: Model A head combustion chamber shape

That is a good design as it allows good flow between the intake valve and the cyl. The late Harley-Davidson, as well as Indian and even Briggs & Stratton used a similar design, as well as my new heads. A guy named Jerry Silberstein also made a similar head here in CA, built as a replacement head for A's, it looked like a stock head on the outside and ran very well. Yours looks like it has been run, and I think has enough water passages to do the deed.
Jim Brierley is offline   Reply With Quote
Old 09-12-2018, 11:37 AM   #7
updraught
Senior Member
 
updraught's Avatar
 
Join Date: Feb 2015
Location: Australia
Posts: 1,133
Default Re: Model A head combustion chamber shape

Probably made for speedway.

I've got an alloy head with more standard chamber, and no water pump provision, just a hose pipe at the front. Local made.

I still have some parts I was given as a kid by a guy who speedway raced a Model A.

I've only been to the speedway once. It was in Broome, Western Australia (out in the sticks).
The camp ground was next to the speedway. It was so noisy in the camp ground we decided to join them.
We met up with the guys that had serviced our car that day. There was a lot of beer and noise involved, I remember that.
updraught is offline   Reply With Quote
Old 09-12-2018, 01:53 PM   #8
CHARLIE YAPP
Junior Member
 
CHARLIE YAPP's Avatar
 
Join Date: May 2011
Location: OUTSIDE CINCINNATI OH
Posts: 6
Default Re: Model A head combustion chamber shape

Could you please show the other side. Is this a two piece head?
It could be a Norm "Frick" or Robert "Roof" head if a 2 pc. . . .Or as you think made in Australia or New Zealand

A "R&R" (Robert Roof) 2 pc was sold on Ebay about 5 years ago for $4500.00. Go figure.

The "turbulence" chamber stepping design has been tried since Bangers were invented. Whether it actually works (facts/tests) or not on a four banger Model A, B, T has not been published to my knowledge. It may have an effect but who knows? Some of these "shapes" do not hold up well on a dyno compared to the basic "Ricardo" one step chambers (think Winfield heads).
What I mean by that is all things compared, chamber volume (compression ratio) and flame front are really the deciding factors. Heavy thick walled castings also hold heat steady and help a lot toward smooth operation.

Dennis Piranio has run the Donovon Model "D" flathead (heavily modified) at Bonneville and I believe it has the two steps and he might be able to share his Dyno results and thoughts.

I have to add because J.B. did: My iron and aluminum Lion Speed Head have a single stepped Ricardo version and dyno at the upper ends of 113 HP and excellent torque at 7:1 CR at 3200 rpm and of course the spark plugs are over the pistons for a superior flame front.
CHARLIE YAPP is offline   Reply With Quote
Old 09-12-2018, 04:04 PM   #9
Kahuna
Senior Member
 
Kahuna's Avatar
 
Join Date: May 2010
Location: NorCal
Posts: 2,617
Default Re: Model A head combustion chamber shape

"My iron and aluminum Lion Speed Head have a single stepped Ricardo version and dyno at the upper ends of 113 HP and excellent torque at 7:1 CR at 3200 rpm".

Now that is impressive at only 3200 rpm. WOW. 113 HP @ 3200?
I'd love to know the rest of the engine combination?
Jim
Kahuna is offline   Reply With Quote
Old 09-12-2018, 04:31 PM   #10
tjw
Senior Member
 
tjw's Avatar
 
Join Date: Jun 2011
Location: Australia
Posts: 229
Default Re: Model A head combustion chamber shape

Quote:
Originally Posted by Kahuna View Post
To me,it appears that someone knew what he was doing.
I'd fix whatever needs to be fixed & run that thing. I think
it would out-perform any other Model A/B flathead.
What's the other side look like?
Jim
Jim
I will take some photos of the top and also the inside of the head for you. It is a two piece head.
tjw is offline   Reply With Quote
Old 09-12-2018, 10:38 PM   #11
Richard in Anaheim CA
Senior Member
 
Richard in Anaheim CA's Avatar
 
Join Date: May 2010
Location: Anaheim California
Posts: 390
Default Re: Model A head combustion chamber shape

I read that sentence to be excellent "torque" at 3200 RPM. If that is true the maximum horsepower reading is likely to be considerably higher.
Richard in Anaheim CA is offline   Reply With Quote
Old 09-13-2018, 10:27 AM   #12
Kahuna
Senior Member
 
Kahuna's Avatar
 
Join Date: May 2010
Location: NorCal
Posts: 2,617
Default Re: Model A head combustion chamber shape

Exactly why I questioned it.
Wonder if I'll see an answer?

And thanks, tjw
Jim
Kahuna is offline   Reply With Quote
Old 09-13-2018, 11:47 AM   #13
Jim Brierley
Senior Member
 
Join Date: Jun 2010
Location: Temecula, CA
Posts: 2,801
Default Re: Model A head combustion chamber shape

tjr, The Silberstein I spoke of was a 1-piece casting.
Jim Brierley is offline   Reply With Quote
Old 09-13-2018, 03:04 PM   #14
updraught
Senior Member
 
updraught's Avatar
 
Join Date: Feb 2015
Location: Australia
Posts: 1,133
Default Re: Model A head combustion chamber shape

Quote:
Originally Posted by Kahuna View Post
"My iron and aluminum Lion Speed Head have a single stepped Ricardo version and dyno at the upper ends of 113 HP and excellent torque at 7:1 CR at 3200 rpm".

Now that is impressive at only 3200 rpm. WOW. 113 HP @ 3200?
I'd love to know the rest of the engine combination?
Jim
It's on the web

http://www.modelaparts.net/dynosheets.htm/lionmod.htm
updraught is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Sponsored Links (Register now to hide all advertisements)


All times are GMT -5. The time now is 09:05 AM.