Early 300 versus Late 300

Reply Subscribe

Thread Tools

Search this Thread

06-24-2011, 03:11 PM

Truckster17

Freshman User

Thread Starter

Join Date: Jun 2009

Posts: 42

Likes: 0

Received 0 Likes on 0 Posts

Early 300 versus Late 300

I need to find another motor for my 69 F250.

I was told by an older Ford mechanic that the early 300 (65-71 or 72) is different from the newer 300s (73-79 and also 80+) and they are not interchangeable.

Is this true? Or can I use any 65-79 300?

Reply Like

06-24-2011, 03:28 PM

Rogue_Wulff

Post Fiend

Join Date: Dec 2007

Location: Lost

Posts: 8,521

Likes: 0

Received 10 Likes on 10 Posts

There are some changes thru the years, but even the newest 300 could be adapted to use in your early model truck.
Up to 86 would be a direct swap, with a few minor parts needed to be changed. 87+ would be a bit more complex, but still doable.
This is assuming you are getting a complete engine, not just a reman short or long block.

Reply Like

06-24-2011, 04:12 PM

Truckster17

Freshman User

Thread Starter

Join Date: Jun 2009

Posts: 42

Likes: 0

Received 0 Likes on 0 Posts

I would like to retain all of my current accessories, so maybe just a short block.

Reply Like

06-24-2011, 07:34 PM

fordman75

Lead Driver

Join Date: Dec 2000

Location: South central, Minnesota

Posts: 5,824

Likes: 8

Received 27 Likes on 24 Posts

Your old Ford mechanic is mistaken!

The very early 300's ( 65-66 ) had a different thrust bearing on the crankshaft. Then in 68 they changed the piston pin diameter from .912" to .972". Which if you plan on using a whole different engine none of this matters.

Like Rogue said any 65-86 300 will be pretty much a direct bolt in. You may need to swap the oil pan and pick up tube off your current engine ( depending on what year your replacement is ) . And like you mentioned you'll want to swap the accessories off your engine onto your replacement. And you may also want to swap in your distributor if you want to keep the stock points set up.

A shortblock is just the block with the rotating assembly, no head. A long block is a shortblock with a cylinder head. If you are buying a reman'd engine you'll need all the bolt on parts/accessories from your current engine. So make sure to keep your current engine until you are positive you've got everything off it you need.

Reply Like

06-24-2011, 09:07 PM

F-250 restorer

Lead Driver

Join Date: Mar 2008

Location: Near Los Angeles

Posts: 6,571

Likes: 19

Received 133 Likes on 116 Posts

There are some differences. The quality of the alloy in the block is the first that comes to mind. Ford also changed the size of the cam journals around 84. About the same time the length of the valves changed too.

Reply Like

06-24-2011, 09:25 PM

fordman75

Lead Driver

Join Date: Dec 2000

Location: South central, Minnesota

Posts: 5,824

Likes: 8

Received 27 Likes on 24 Posts

You sure about the cams?

I've dealt with a lot of 300's and have never heard of that.

Reply Like

06-24-2011, 10:40 PM

F-250 restorer

Lead Driver

Join Date: Mar 2008

Location: Near Los Angeles

Posts: 6,571

Likes: 19

Received 133 Likes on 116 Posts

<!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:TrackMoves/> <w:TrackFormatting/> <w:PunctuationKerning/> <w:ValidateAgainstSchemas/> <w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid> <w:IgnoreMixedContent>false</w:IgnoreMixedContent> <w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText> <w

oNotPromoteQF/> <w:LidThemeOther>EN-US</w:LidThemeOther> <w:LidThemeAsian>X-NONE</w:LidThemeAsian> <w:LidThemeComplexScript>X-NONE</w:LidThemeComplexScript> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> <w

ontGrowAutofit/> <w:SplitPgBreakAndParaMark/> <w

ontVertAlignCellWithSp/> <w

ontBreakConstrainedForcedTables/> <w

ontVertAlignInTxbx/> <w:Word11KerningPairs/> <w:CachedColBalance/> </w:Compatibility> <m:mathPr> <m:mathFont m:val="Cambria Math"/> <m:brkBin m:val="before"/> <m:brkBinSub m:val="--"/> <m:smallFrac m:val="off"/> <m:dispDef/> <m:lMargin m:val="0"/> <m:rMargin m:val="0"/> <m:defJc m:val="centerGroup"/> <m:wrapIndent m:val="1440"/> <m:intLim m:val="subSup"/> <m:naryLim m:val="undOvr"/> </m:mathPr></w:WordDocument> </xml><![endif]--><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority

9; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;} </style> <![endif]--> 4.9L CAM BEARING HOUSING BORE CHANGE
Revised Cam Bearing housing Bore On
1985-87 Ford 300 CID (4.9L) Engines
The Form Motor Company has revised the cam bearing housing bore on
Ford 300 CID (4.9L) engines manufactured after June 4th, 1985.
Previously all four housing bores measured 2.1440. The late style
block with the casting number E1TE-6015AA, has the following cam
bearing housing bore dimensions:
Location Part # Bore Diameter
1 E5TZ-6261A 2.1590
2 E5TZ-6262A 2.1440
3 E5TZ-6262A 2.1440
4 E5TZ-6261A 2.1590

AERA members are cautioned to check each cylinder block's cam
bearing housing bore for positive identification.

Reply Like

Early 300 versus Late 300

Early 300 versus Late 300

Trending Topics