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Re: Possible 261 block with the mystery "M" casting mark Hotrod Lincoln #1286526 11/07/2018 11:16 PM
Joined: Jan 2001 Posts: 5,337 Snohomish,WA,USA P Pre '68 Dave 'Bolter
Pre '68 Dave 'Bolter P Joined: Jan 2001 Posts: 5,337 Snohomish,WA,USA	Originally Posted by Hotrod Lincoln They both have the same stroke but the 261 crankshaft is forged, not cast. Jerry Not sure what you are thinking here Jerry, I have never seen a cast crank in any 235. 1954-63 235 and 261 cranks are "forged" 3701488. See the USA in your vintage Chevrolet! My Blog

Entire Thread
Subject	Posted By	Posted
Possible 261 block with the mystery "M" casting mark	GMCanada9430	11/07/2018 4:50 AM
Re: Possible 261 block with the mystery "M" casting mark	sstock	11/07/2018 1:14 PM
Re: Possible 261 block with the mystery "M" casting mark	Grigg	11/07/2018 1:25 PM
Re: Possible 261 block with the mystery "M" casting mark	GMCanada9430	11/07/2018 3:37 PM
Re: Possible 261 block with the mystery "M" casting mark	Pre '68 Dave	11/07/2018 3:42 PM
Re: Possible 261 block with the mystery "M" casting mark	Hotrod Lincoln	11/07/2018 3:59 PM
Re: Possible 261 block with the mystery "M" casting mark	Pre '68 Dave	11/07/2018 11:16 PM
Re: Possible 261 block with the mystery "M" casting mark	Mike B	11/07/2018 4:08 PM
Re: Possible 261 block with the mystery "M" casting mark	Dragsix	11/07/2018 4:36 PM
Re: Possible 261 block with the mystery "M" casting mark	GMCanada9430	11/07/2018 7:13 PM
Re: Possible 261 block with the mystery "M" casting mark	Curt B.	11/07/2018 7:58 PM
Re: Possible 261 block with the mystery "M" casting mark	Hotrod Lincoln	11/07/2018 8:19 PM
Re: Possible 261 block with the mystery "M" casting mark	Curt B.	11/07/2018 10:42 PM
Re: Possible 261 block with the mystery "M" casting mark	Hotrod Lincoln	11/07/2018 10:54 PM
Re: Possible 261 block with the mystery "M" casting mark	Dragsix	11/08/2018 3:40 PM
Re: Possible 261 block with the mystery "M" casting mark	Fox	11/09/2018 4:38 AM
Re: Possible 261 block with the mystery "M" casting mark	Leo	11/11/2018 11:13 AM
Re: Possible 261 block with the mystery "M" casting mark	tclederman	11/11/2018 6:12 PM
Re: Possible 261 block with the mystery "M" casting mark	GMCanada9430	11/12/2018 4:23 AM
Re: Possible 261 block with the mystery "M" casting mark	Grant_Bowker	11/15/2018 1:46 AM
Re: Possible 261 block with the mystery "M" casting mark	GMCanada9430	11/19/2018 3:40 AM

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