The Ford Barn

Don Mills · 10-13-2022, 05:40 PM

My engine has valves with 11/32" (.340") stems
Does anyone make a valve guide or will I have to install an original size(.311) and bore it?

Don Mills · 10-13-2022, 05:45 PM

Clarify- engine is a B 4cyl

Bob C · 10-13-2022, 06:26 PM

The valves and guides I got at Bert's are 11/32".

Gene F · 10-13-2022, 06:48 PM

I have had engines witht he big valves. By far the IB-330 cam makes the diff

Jim Brierley · 10-14-2022, 11:18 AM

Quote:

Originally Posted by Gene F

I have had engines witht he big valves. By far the IB-330 cam makes the difference. The lift is almost 1/4" more.

1/4" more? NOT! The Stipe 330 has .330" of lobe lift, Most stock B cams have .305", the latest B has .339".

Theoretically big valves improve performance, and they do but are they worth the price??? I dynoed one of my B/C engines with stock size valves at 107 HP.

BRENT in 10-uh-C · 10-14-2022, 11:30 AM

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Quote:

Originally Posted by Gene F

I have had engines witht he big valves. By far the IB-330 cam makes the difference. The lift is almost 1/4" more.

Quote:

Originally Posted by Jim Brierley

1/4" more? NOT! The Stipe 330 has .330" of lobe lift, Most stock B cams have .305", the latest B has .339".

Theoretically big valves improve performance, and they do but are they worth the price??? I dynoed one of my B/C engines with stock size valves at 107 HP.

Yeah, Don Mills is talking something totally different than what Gene is. The Valve stem, -not the valve head is the size we are discussing.

Don, the issue you have is the stock Model-A valve uses a mushroom configuration on the end that requires a two-piece guide be used. A one-piece guide will need a valve that uses a straight stem of the 0.340" ID. Both Snyders and Brian at Antique Engine Rebuilding offer a 1.500" valve that uses a one-piece valve guide that presses into the stock Model-B lifter bore.

While AAR does offer a larger 1.750 headed valve (-that uses a 0.340" stem), unless you have a sonic checker to check deck thickness, I would not suggest you using the O/S valve on a B engine as deck cracks are possible.

Ohh, ...and welcome to Fordbarn Don!!

johnneilson · 10-14-2022, 12:27 PM

Quote:

Originally Posted by BRENT in 10-uh-C

Yeah, Don Mills is talking something totally different than what Gene is. The Valve stem, -not the valve head is the size we are discussing.

Don, the issue you have is the stock Model-A valve uses a mushroom configuration on the end that requires a two-piece guide be used. A one-piece guide will need a valve that uses a straight stem of the 0.340" ID. Both Snyders and Brian at Antique Engine Rebuilding offer a 1.500" valve that uses a one-piece valve guide that presses into the stock Model-B lifter bore.

While AAR does offer a larger 1.750 headed valve (-that uses a 0.340" stem), unless you have a sonic checker to check deck thickness, I would not suggest you using the O/S valve on a B engine as deck cracks are possible.

Ohh, ...and welcome to Fordbarn Don!!

Brett,

and to add to the conversation, be careful of adding seats to the motors, normal seats for "modern" motors are too thick, causing cracking.

There are solid guides available in the proper ~.590 dia with 11/32" bores

John

BRENT in 10-uh-C · 10-14-2022, 01:24 PM

Quote:

Originally Posted by johnneilson

Brett,

and to add to the conversation, be careful of adding seats to the motors, normal seats for "modern" motors are too thick, causing cracking.

There are solid guides available in the proper ~.590 dia with 11/32" bores

John

Good point John. I have good luck adding seats to B engines using SB Industries valve seat for a 1980 Chevrolet Chevette which has an OD of 1.625" and about 0.218" deep, however that is for the stock size 1.500" valve. If a deck has been milled some in the past, I typically will reduce the depth of counterbore by that much and then just grind the seat's protrusion by that much prior to cutting the seat. Seems to work ok.

Gene F · 10-14-2022, 05:32 PM

corrected. Thanks guys

Jim Brierley · 10-15-2022, 11:10 AM

There's not much need for seats in the intakes unless they have been ground WAY DOWN, if installing bigger intakes, there id no need whatsoever. Intakes run much cooler than exhausts. Exhausts are a different story!

10-13-2022, 05:40 PM	#1
Don Mills Junior Member Join Date: Sep 2022 Posts: 2	Valve size My engine has valves with 11/32" (.340") stems Does anyone make a valve guide or will I have to install an original size(.311) and bore it?

10-13-2022, 05:45 PM	#2
Don Mills Junior Member Join Date: Sep 2022 Posts: 2	Re: Valve size Clarify- engine is a B 4cyl

10-13-2022, 06:26 PM	#3
Bob C Senior Member Join Date: May 2010 Location: So Cal Posts: 8,757	Re: Valve size The valves and guides I got at Bert's are 11/32".

10-13-2022, 06:48 PM	#4
Gene F Senior Member Join Date: Mar 2012 Location: Ohio Posts: 1,978	Re: Valve size I have had engines witht he big valves. By far the IB-330 cam makes the diff Last edited by Gene F; 10-14-2022 at 05:32 PM.

10-14-2022, 05:32 PM	#9
Gene F Senior Member Join Date: Mar 2012 Location: Ohio Posts: 1,978	Re: Valve size corrected. Thanks guys

10-15-2022, 11:10 AM	#10
Jim Brierley Senior Member Join Date: Jun 2010 Location: Temecula, CA Posts: 4,093	Re: Valve size There's not much need for seats in the intakes unless they have been ground WAY DOWN, if installing bigger intakes, there id no need whatsoever. Intakes run much cooler than exhausts. Exhausts are a different story!