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rod to piston side clearance #1565616 01/19/14 09:30 PM 01/19/14 09:30 PM
Joined: Jan 2014 Posts: 6 Pennsylvania S smallblockarrow OP member
smallblockarrow OP member S Joined: Jan 2014 Posts: 6 Pennsylvania	I have a problem with my 340 build.Diamond pistons do not fit the stock rod. Rod small end width 1.202 piston pin tower width 1.201 Has anyone had this problem with diamonds before??

Re: rod to piston side clearance [Re: smallblockarrow] #1565617 01/19/14 09:48 PM 01/19/14 09:48 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Quote: I have a problem with my 340 build.Diamond pistons do not fit the stock rod. Rod small end width 1.202 piston pin tower width 1.201 Has anyone had this problem with diamonds before?? Nope never had that issue.. are they made for a chevy rod(whats the pin size) but you might want to call Diamond tomorrow... should be a TON of side movement

Re: rod to piston side clearance [Re: MR_P_BODY] #1565618 01/19/14 10:37 PM 01/19/14 10:37 PM
Joined: Jan 2014 Posts: 6 Pennsylvania S smallblockarrow OP member
smallblockarrow OP member S Joined: Jan 2014 Posts: 6 Pennsylvania	Stock 340 pin.I believe I should have .050" on each side minimum.

Re: rod to piston side clearance [Re: smallblockarrow] #1565619 01/19/14 10:39 PM 01/19/14 10:39 PM
Joined: Jul 2013 Posts: 561 USA B B3RE mopar
B3RE mopar B Joined: Jul 2013 Posts: 561 USA	Quote: I have a problem with my 340 build.Diamond pistons do not fit the stock rod. Rod small end width 1.202 piston pin tower width 1.201 Has anyone had this problem with diamonds before?? They are probably designed for the magnum rods which are narrower on the pin end. Mike Beachel I didn't write the rules of math nor create the laws of physics, I am just bound by them.

Re: rod to piston side clearance [Re: B3RE] #1565620 01/19/14 11:16 PM 01/19/14 11:16 PM
Joined: Jan 2014 Posts: 6 Pennsylvania S smallblockarrow OP member
smallblockarrow OP member S Joined: Jan 2014 Posts: 6 Pennsylvania	I just noticed the the job # on the bottom of the pin tower doesn't match # on the box or the card that was in the box.Maybe that has something to do with it.the last digit is wrong,9 instead of a 6.Calling Diamond tomorrow.We already sent these pistons back once because they came with the wrong compression height.Yes they could be for a magnum or a chevy. I don't know width of a chevy rod.

Re: rod to piston side clearance [Re: smallblockarrow] #1565621 01/19/14 11:29 PM 01/19/14 11:29 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Quote: I just noticed the the job # on the bottom of the pin tower doesn't match # on the box or the card that was in the box.Maybe that has something to do with it.the last digit is wrong,9 instead of a 6.Calling Diamond tomorrow.We already sent these pistons back once because they came with the wrong compression height.Yes they could be for a magnum or a chevy. I don't know width of a chevy rod. Damn your having a rough way to go with those Diamond pistons... lucky for me they are only 10 miles from me... sounds like you got someone elses pistons.. so there might be 2 pissed off people out there

Re: rod to piston side clearance [Re: MR_P_BODY] #1565622 01/19/14 11:52 PM 01/19/14 11:52 PM
Joined: Jan 2014 Posts: 6 Pennsylvania S smallblockarrow OP member
smallblockarrow OP member S Joined: Jan 2014 Posts: 6 Pennsylvania	I don't know. Maybe there is somebody out there building one just like mine but with a different width rod.Maybe I can trade with the other guy. Bore 4.073 C.H. 1.81

Re: rod to piston side clearance [Re: smallblockarrow] #1565623 01/20/14 12:02 AM 01/20/14 12:02 AM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Quote: I don't know. Maybe there is somebody out there building one just like mine but with a different width rod.Maybe I can trade with the other guy. Bore 4.073 C.H. 1.81 Thats a odd ball diameter

Re: rod to piston side clearance [Re: MR_P_BODY] #1565624 01/20/14 08:16 PM 01/20/14 08:16 PM
Joined: Jan 2014 Posts: 6 Pennsylvania S smallblockarrow OP member
smallblockarrow OP member S Joined: Jan 2014 Posts: 6 Pennsylvania	yes it is an odd size. That is where the cylinders honed up nice, straight and round.so I decided to change bore size and C.H. for close to 10 to1 comp.Diamond allowed us to change any two things on piston no extra charge.I am freshening up motor since rebuild 27 years ago.I have removed the forged speed pro low compression pistons,8 to 1 comp., in favor of the diamonds.On another note, Diamond responded by Email to myself and talked to my machinist on the phone today.They told me it is common on aluminum rods and extra wide OEM rods.That is why they ask for that info on customs and they would take a cut on the pin towers.But my argument is the rods are factory width 1.2",some are up to +.002",and some down to -.0005" My machinist is still working on them to see if they will help out.I guess maybe I was confused,I thought we started with a 340 piston and made changes from there.They said the job number on the build sheet was a mistake and that was a LS1 number. The number on the piston is right and the one traced to my machinist.So I guess these 700.00$ pistons are going to cost me a little bit more.Yes well, its only money, I'll make more tomorrow.

Re: rod to piston side clearance [Re: smallblockarrow] #1565625 01/20/14 10:07 PM 01/20/14 10:07 PM
Joined: Aug 2003 Posts: 1,313 Charlotte, NC L LSP pro stock
LSP pro stock L Joined: Aug 2003 Posts: 1,313 Charlotte, NC	The small end of the rods can be narrowed up .050" per side, easy way out.

Re: rod to piston side clearance [Re: smallblockarrow] #1565626 01/20/14 10:22 PM 01/20/14 10:22 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Quote: yes it is an odd size. That is where the cylinders honed up nice, straight and round.so I decided to change bore size and C.H. for close to 10 to1 comp.Diamond allowed us to change any two things on piston no extra charge.I am freshening up motor since rebuild 27 years ago.I have removed the forged speed pro low compression pistons,8 to 1 comp., in favor of the diamonds.On another note, Diamond responded by Email to myself and talked to my machinist on the phone today.They told me it is common on aluminum rods and extra wide OEM rods.That is why they ask for that info on customs and they would take a cut on the pin towers.But my argument is the rods are factory width 1.2",some are up to +.002",and some down to -.0005" My machinist is still working on them to see if they will help out.I guess maybe I was confused,I thought we started with a 340 piston and made changes from there.They said the job number on the build sheet was a mistake and that was a LS1 number. The number on the piston is right and the one traced to my machinist.So I guess these 700.00$ pistons are going to cost me a little bit more.Yes well, its only money, I'll make more tomorrow. Well based on this I assume your machinist called in the order so its not on you.. either he can/will correct the issue OR he will send them back for correction which HE should cover(if its his fault on the order)

Re: rod to piston side clearance [Re: MR_P_BODY] #1565627 01/23/14 08:03 PM 01/23/14 08:03 PM
Joined: Jan 2014 Posts: 6 Pennsylvania S smallblockarrow OP member
smallblockarrow OP member S Joined: Jan 2014 Posts: 6 Pennsylvania	Talked to my machinist last night. I was right, he did order 340 part number with alterations.He is working on sending them back for modification.Here is the best part, not only was the job # on the build sheet and on the box an LS1 #, the one on the pistons is a hemi #.So it seems as though my pistons don't exist!!

Re: rod to piston side clearance [Re: smallblockarrow] #1565628 01/23/14 08:30 PM 01/23/14 08:30 PM
Joined: Nov 2004 Posts: 6,890 North Alabama M Monte_Smith master
Monte_Smith master M Joined: Nov 2004 Posts: 6,890 North Alabama	Cut the rods......problem solved. No way I would have them machine the inside of the pin bosses Monte

Re: rod to piston side clearance [Re: smallblockarrow] #1565629 01/23/14 11:03 PM 01/23/14 11:03 PM
Joined: Jun 2006 Posts: 916 MB,CAN PC-CHARGER super stock
PC-CHARGER super stock Joined: Jun 2006 Posts: 916 MB,CAN	I had a similar issue with my Diamond pistons and Eagle rods but in a big block build. My machinist just narrowed the pin end of the rod. No problems with the engine assembly and his been running since.

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