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Is a 360 manufactured in 1971 more desirable? #137839 10/16/08 10:28 PM 10/16/08 10:28 PM
Joined: Jul 2007 Posts: 85 Midland, Tx R rjones OP member
rjones OP member R Joined: Jul 2007 Posts: 85 Midland, Tx	I have heard they are due to thicker cylinder walls. Any truth in this? Thanks, Roger

Re: Is a 360 manufactured in 1971 more desirable? [Re: rjones] #137840 10/16/08 10:37 PM 10/16/08 10:37 PM
Joined: Feb 2004 Posts: 4,501 Gainesville,FL G goldmember master
goldmember master G Joined: Feb 2004 Posts: 4,501 Gainesville,FL	Urban myth.

Re: Is a 360 manufactured in 1971 more desirable? [Re: rjones] #137841 10/16/08 10:46 PM 10/16/08 10:46 PM
Joined: Jan 2006 Posts: 3,535 Canuckville 68Cbarge master
68Cbarge master Joined: Jan 2006 Posts: 3,535 Canuckville	Yes,it is true that the block is cast differently than later ones and do have thicker walls. Desirable? Well it depends on who you ask. If you plan on making a monster 406 C.I. stroker small block (4" crank,massive bore job & oversized pistons,Eddy heads) yes the 71 72 360's tend to hold up better in racing conditions. As a core ,the value is no different than any other 360 block,IMO. Hope this helps. '68 Newport Custom Barge on a Budget!! BOAB 1973 Satellite WAGON! 318- 3 on the tree!! 2008 Chrysler 300c HEMI!

Re: Is a 360 manufactured in 1971 more desirable? [Re: 68Cbarge] #137842 10/16/08 11:03 PM 10/16/08 11:03 PM
Joined: Mar 2003 Posts: 9,100 Rogue River, OR Jeremiah master
Jeremiah master Joined: Mar 2003 Posts: 9,100 Rogue River, OR	Quote: Yes,it is true that the block is cast differently than later ones and do have thicker walls. Desirable? Well it depends on who you ask. If you plan on making a monster 406 C.I. stroker small block (4" crank,massive bore job & oversized pistons,Eddy heads) yes the 71 72 360's tend to hold up better in racing conditions. As a core ,the value is no different than any other 360 block,IMO. Hope this helps. Our resident smallblock guru, as well as several others, have debunked this myth many times. No block cn be assumed better than another based on production/casting date until it is sonic checked. I went through several block before finding a good specimen for my 408. Also, one does not need to ovebore more than they would on any other (ie stock stroke) rebuild with a 4" stroke crank, hence the nomenclature "stroker motor"...

Re: Is a 360 manufactured in 1971 more desirable? [Re: 68Cbarge] #137843 10/16/08 11:03 PM 10/16/08 11:03 PM
Joined: Feb 2004 Posts: 4,501 Gainesville,FL G goldmember master
goldmember master G Joined: Feb 2004 Posts: 4,501 Gainesville,FL	My first thought is that the manufacturers try their best to cut cost and make everthing lighter therefore less material,iron,it makes sense the later blocks would always be thinner. From guys that sonic check and build them for a living it appears there is little merit to the old myth. If your building a engine to make good hp have it sonic checked first. We have cracked cylinder walls in the "supposed" thick wall early blocks in mild strip engines(500+hp).

Re: Is a 360 manufactured in 1971 more desirable? [Re: rjones] #137844 10/16/08 11:20 PM 10/16/08 11:20 PM
Joined: May 2008 Posts: 5,399 Aurora, Colorado 451Mopar master
451Mopar master Joined: May 2008 Posts: 5,399 Aurora, Colorado	Yes, the early blocks are a bit better. It is not the cylinder wall thickness, but the thickness if the webbing above the mains. On the early blocks the webbing is the full thickness of the main, but the later blocks the webbing is about 1/2 the thickness.

Re: Is a 360 manufactured in 1971 more desirable? [Re: 451Mopar] #137845 10/16/08 11:22 PM 10/16/08 11:22 PM
Joined: Jan 2006 Posts: 3,535 Canuckville 68Cbarge master
68Cbarge master Joined: Jan 2006 Posts: 3,535 Canuckville	Quote: Yes, the early blocks are a bit better. It is not the cylinder wall thickness, but the thickness if the webbing above the mains. On the early blocks the webbing is the full thickness of the main, but the later blocks the webbing is about 1/2 the thickness. Thanks for the correction!! '68 Newport Custom Barge on a Budget!! BOAB 1973 Satellite WAGON! 318- 3 on the tree!! 2008 Chrysler 300c HEMI!

Re: Is a 360 manufactured in 1971 more desirable? [Re: 451Mopar] #137846 10/16/08 11:32 PM 10/16/08 11:32 PM
Joined: Feb 2004 Posts: 4,501 Gainesville,FL G goldmember master
goldmember master G Joined: Feb 2004 Posts: 4,501 Gainesville,FL	Got pics? In what year did this change? Last edited by goldmember; 10/16/08 11:33 PM.

Re: Is a 360 manufactured in 1971 more desirable? [Re: rjones] #137847 10/17/08 12:54 AM 10/17/08 12:54 AM
Joined: Dec 2003 Posts: 22,696 Bitopia J jcc If you can't dazzle em with diamonds..
jcc If you can't dazzle em with diamonds.. J Joined: Dec 2003 Posts: 22,696 Bitopia	I 've got an early 360 72?, and sonic tested it 12 places per cyl, and it was awesome, over .220 everywhere. I could dig up the test sheet, I tested later 3 more pre 74 blocks and none were as close everywhere. I say the myth is true about early blocks, just what defines early is the puzzle. Reality check, that half the population is smarter then 50% of the people and it's a constantly contested fact.

Re: Is a 360 manufactured in 1971 more desirable? [Re: jcc] #137848 10/17/08 01:06 AM 10/17/08 01:06 AM
Joined: Feb 2004 Posts: 4,501 Gainesville,FL G goldmember master
goldmember master G Joined: Feb 2004 Posts: 4,501 Gainesville,FL	That just states the case for testing ,but doesn't touch the original question.

Re: Is a 360 manufactured in 1971 more desirable? [Re: goldmember] #137849 10/17/08 01:26 AM 10/17/08 01:26 AM
Joined: Dec 2003 Posts: 22,696 Bitopia J jcc If you can't dazzle em with diamonds..
jcc If you can't dazzle em with diamonds.. J Joined: Dec 2003 Posts: 22,696 Bitopia	Quote: That just states the case for testing ,but doesn't touch the original question. Well, the earliest block of the batch did test the best. Reality check, that half the population is smarter then 50% of the people and it's a constantly contested fact.

Re: Is a 360 manufactured in 1971 more desirable? [Re: jcc] #137850 10/17/08 01:30 AM 10/17/08 01:30 AM
Joined: Feb 2004 Posts: 4,501 Gainesville,FL G goldmember master
goldmember master G Joined: Feb 2004 Posts: 4,501 Gainesville,FL	So each year gets thinner?

Re: Is a 360 manufactured in 1971 more desirable? [Re: goldmember] #137851 10/17/08 05:49 AM 10/17/08 05:49 AM
Joined: Nov 2006 Posts: 1,086 Baton Rouge, La. StandOnIt super stock
StandOnIt super stock Joined: Nov 2006 Posts: 1,086 Baton Rouge, La.	On a 360 with a 4" crank, you need to over bore only .020 to make a 406". To make a 408" you need a .030 overbore. You don't really need alot of cylinder thickness to make a stroker that small. If you are looking to make a huge small block stroker, then ya start checking them. I took a 97 5.9 to a 406" with no problem at all with high compression and lots of cylinder pressures. With good head gaskets, she takes care of buisiness. 76' Volare, 5.9 magnum w/Iron heads. New best 10.68 at 123 mph 1/4 mile.

Re: Is a 360 manufactured in 1971 more desirable? [Re: StandOnIt] #137852 10/17/08 11:06 AM 10/17/08 11:06 AM
Joined: Feb 2004 Posts: 4,501 Gainesville,FL G goldmember master
goldmember master G Joined: Feb 2004 Posts: 4,501 Gainesville,FL	No one said you can't bore a block blindly and run it,did you have the block sonic checked,have any info. Whats huge HP? 400-450-500-550-600-650-700-750-800???

Re: Is a 360 manufactured in 1971 more desirable? [Re: rjones] #137853 10/17/08 01:39 PM 10/17/08 01:39 PM
Joined: Jan 2007 Posts: 169 arizona V VPrace member
VPrace member V Joined: Jan 2007 Posts: 169 arizona	Quote: I have heard they are due to thicker cylinder walls. Any truth in this? Thanks, Roger wasn't the original story that early 360 blocks were cast with the 340 molds and therefore were only bored to 4 ? that was supposed to be why the walls were thicker?

Re: Is a 360 manufactured in 1971 more desirable? [Re: goldmember] #137854 10/17/08 01:45 PM 10/17/08 01:45 PM
Joined: Oct 2006 Posts: 4,765 Q quick77rt Parts Problem
quick77rt Parts Problem Q Joined: Oct 2006 Posts: 4,765	So each year gets thinner? Yes they do, my friends 2006 was running bad, pulled a head and BAM it was so new of a block there were only pistons and anti-freeze, no sign of cylinder walls. Now we dont know what to do? Sorry...had to. Quote: So each year gets thinner?

Re: Is a 360 manufactured in 1971 more desirable? [Re: VPrace] #137855 10/17/08 01:48 PM 10/17/08 01:48 PM
Joined: Jan 2005 Posts: 4,441 Michigan MarkZ Worthy
MarkZ Worthy Joined: Jan 2005 Posts: 4,441 Michigan	Differences in early vs later 360 are probably so minute it's not even worth the headache of trying to find one. The only real desirable LA 360 blocks were built from 89'-91'. They had provisions for roller cam shafts. If you're not concerned about that, just find one and build it. 1987 Fifth Avenue - 512/518/D60

Re: Is a 360 manufactured in 1971 more desirable? [Re: VPrace] #137856 10/17/08 02:53 PM 10/17/08 02:53 PM
Joined: Dec 2003 Posts: 5,314 Carstairs, Alberta, Canada dave571 master
dave571 master Joined: Dec 2003 Posts: 5,314 Carstairs, Alberta, Canada	Quote: wasn't the original story that early 360 blocks were cast with the 340 molds and therefore were only bored to 4 ? that was supposed to be why the walls were thicker? That's what I heard also. That these were desireable, because they could be bored out, and made into a 340 if need be. IIRC you could even by some sort of spacers for the main bearings to work (use the 340/318 crank) That was pre stroker fad days of course. These days, use a 4.0 crank and go nuts

Re: Is a 360 manufactured in 1971 more desirable? [Re: rjones] #137857 10/17/08 06:30 PM 10/17/08 06:30 PM
Joined: Jan 2003 Posts: 5,894 Florida Locomotion master
Locomotion master Joined: Jan 2003 Posts: 5,894 Florida	With casting variances and potential core shift, there are no guarantees in any year. You can always add a little hard-block, perhaps 1/2 way up, if cylinder wall stability is a concern.

Re: Is a 360 manufactured in 1971 more desirable? [Re: rjones] #137858 10/17/08 07:45 PM 10/17/08 07:45 PM
Joined: Jan 2003 Posts: 1,359 Buzzard County, FL IronWolf pro stock
IronWolf pro stock Joined: Jan 2003 Posts: 1,359 Buzzard County, FL	The consensus is that all blocks should be sonic checked. After studying block casting, etc, I am amazed (and doubt) that any two cast blocks would be exactly the same. That statement is documented by looking at the foundry problems the first race hemis had in '64. They had to be manually massaged by engineers to produce a workable block. After looking at the manufacturing techniques (sand casting), it's a miracle that any engine blocks can be produced somewhat close in spec... Kind of scary, unless you got one of the good blocks.

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