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Re: Valve relief pockets as gas ports??? [Re: 540dust] #189578 01/11/09 11:16 PM 01/11/09 11:16 PM
Joined: Mar 2006 Posts: 9,910 Eighty Four, PA B G Racing master
B G Racing master Joined: Mar 2006 Posts: 9,910 Eighty Four, PA	Quote: I know a guy that welded the notches before too, but the hole was thru the bottom not to the ring groove. The ring groove can be re-dressed [IMG]http://i430.photobucket.com/albums/qq21/ajcasini/max_zpsdppwd9km.jpg[/IMG]

Re: Valve relief pockets as gas ports??? [Re: B G Racing] #189579 01/11/09 11:28 PM 01/11/09 11:28 PM
Joined: Jan 2005 Posts: 3,635 Oakland, MI D dizuster master
dizuster master D Joined: Jan 2005 Posts: 3,635 Oakland, MI	Quote: Quote: I know a guy that welded the notches before too, but the hole was thru the bottom not to the ring groove. The ring groove can be re-dressed Really? I called Diamond getting ring grooves re-cut and they told me no way.... I'd be worried about warping the ring land groove. Most good pistons today are so tight to start with, it wouldn't take much... I'd be getting a new set from whoever screwed them up when they cut them. I mean come on, cutting a hole in 1 is a mistake, cutting all 8 is a joke...

Re: Valve relief pockets as gas ports??? [Re: dizuster] #189580 01/11/09 11:58 PM 01/11/09 11:58 PM
Joined: Mar 2006 Posts: 9,910 Eighty Four, PA B G Racing master
B G Racing master Joined: Mar 2006 Posts: 9,910 Eighty Four, PA	What's so hard about cutting ring lands?We have re-cut them to go to a thicker ring and have also relocated the ring lands.The rings is what conforms to the bore.The top portion of the piston is smaller than the bore.Many pistons are cam ground with only the skirt or thrust sides conforming to the bore,with specific clearences. [IMG]http://i430.photobucket.com/albums/qq21/ajcasini/max_zpsdppwd9km.jpg[/IMG]

Re: Valve relief pockets as gas ports??? [Re: 1976 Aspen] #189581 01/12/09 12:09 AM 01/12/09 12:09 AM
A Anonymous Unregistered
Anonymous Unregistered A	i wouldn't run them. adding radial clearance is one thing, but milling .065 deeper should give you enough room for an .800 lift cam. they look a lot deeper than that. i know it's not what you want to hear but, i think you have 8 new paperweights.

Re: Valve relief pockets as gas ports??? #189582 01/12/09 12:19 AM 01/12/09 12:19 AM
Joined: Mar 2006 Posts: 9,910 Eighty Four, PA B G Racing master
B G Racing master Joined: Mar 2006 Posts: 9,910 Eighty Four, PA	If your going to toss them,send them to us,Curt Jr and Chaz can practice their barnyard techniques. [IMG]http://i430.photobucket.com/albums/qq21/ajcasini/max_zpsdppwd9km.jpg[/IMG]

Re: Valve relief pockets as gas ports??? [Re: B G Racing] #189583 01/12/09 09:12 AM 01/12/09 09:12 AM
Joined: Jan 2005 Posts: 3,635 Oakland, MI D dizuster master
dizuster master D Joined: Jan 2005 Posts: 3,635 Oakland, MI	Quote: What's so hard about cutting ring lands?We have re-cut them to go to a thicker ring and have also relocated the ring lands. That is exactly what Diamond said they would not do. I called them because I was thinking about buying a set of pistons a guy had, but they were metric rings, and I wanted standard 1/16" stuff. I told Diamond I already had the pistons and I wanted to send them back to get the rings re-cut. They said they absolutely would not do that? Should have bought them and sent them to you!

Re: Valve relief pockets as gas ports??? [Re: dizuster] #189584 01/12/09 09:39 AM 01/12/09 09:39 AM
Joined: Mar 2006 Posts: 9,910 Eighty Four, PA B G Racing master
B G Racing master Joined: Mar 2006 Posts: 9,910 Eighty Four, PA	Quote: Quote: What's so hard about cutting ring lands?We have re-cut them to go to a thicker ring and have also relocated the ring lands. That is exactly what Diamond said they would not do. I called them because I was thinking about buying a set of pistons a guy had, but they were metric rings, and I wanted standard 1/16" stuff. I told Diamond I already had the pistons and I wanted to send them back to get the rings re-cut. They said they absolutely would not do that? Should have bought them and sent them to you! Some pistons are not concentric enough to chuck up with out the centering plug left on the top of the piston,once the piston has been machined the stub is knocked off and the top is finished.To re-chuck it can be a pita on some but with a little effort anything can be done. [IMG]http://i430.photobucket.com/albums/qq21/ajcasini/max_zpsdppwd9km.jpg[/IMG]

Re: Valve relief pockets as gas ports??? [Re: B G Racing] #189585 01/12/09 07:18 PM 01/12/09 07:18 PM
Joined: Sep 2007 Posts: 238 Roseau, MN 1976 Aspen OP enthusiast
1976 Aspen OP enthusiast Joined: Sep 2007 Posts: 238 Roseau, MN	Well, despite everybody's advice and opinions, I've decided to run it the way they are. My machinist said he's done this many times with big block chevy's and we all know they're alot more prone to detonation than our stuff. Thanks for all the reply's and I'll keep you updated on when it makes a mess of things

Re: Valve relief pockets as gas ports??? [Re: 1976 Aspen] #189586 01/12/09 09:00 PM 01/12/09 09:00 PM
Joined: Jan 2004 Posts: 13,247 Mt. Vernon, Ohio dartman366 I Live Here
dartman366 I Live Here Joined: Jan 2004 Posts: 13,247 Mt. Vernon, Ohio	Sorry, I would have a serious problem with those slug's,,,,I just hope I am never in the other lane against you. Light travels faster than the speed of sound,,,this is why some people seem bright untill you hear them speak.

Re: Valve relief pockets as gas ports??? [Re: 1976 Aspen] #189587 01/12/09 09:11 PM 01/12/09 09:11 PM
A Anonymous Unregistered
Anonymous Unregistered A	here's a silly question. it's clearly obvious that one of the holes connects with the ring land. where does the other one go??? it's too far inward to connect to the ring land. it looks like it would just go through the top and come out the bottom of the piston near the pin. in any case i do find it interesting that even with all the people telling you all the bad things that can happen, your still willing to chance trashing a motor.

Re: Valve relief pockets as gas ports??? [Re: dartman366] #189588 01/12/09 09:25 PM 01/12/09 09:25 PM
Joined: Oct 2004 Posts: 3,097 back in Georgia dthemi master
dthemi master Joined: Oct 2004 Posts: 3,097 back in Georgia	There are tons of motors out there running way worse than that, and they just don't know it yet. Obviously it would be the right thing to do to get new ones, and had we done that to a customers pistons, we'd buy you a new set along with an apology for delaying you. but if that were all that was between me and going to the track because of time, or budget constraints I'd pound'm in and head on out. Alright I'm ready for my beating now

Re: Valve relief pockets as gas ports??? [Re: dthemi] #189589 01/12/09 09:56 PM 01/12/09 09:56 PM
Joined: Sep 2007 Posts: 238 Roseau, MN 1976 Aspen OP enthusiast
1976 Aspen OP enthusiast Joined: Sep 2007 Posts: 238 Roseau, MN	Dartman- It's not like my motor is going to saw itself in half going down the track DRAM- There is only one little hole. I have .187 in the thinnest spot to make an actual hole in the top of the piston. And no offense to you or anybody else, I've learned to take most information, advice, and opinions with a grain of salt on this board. dthemi- I can understand where you're coming from. I'll keep everybody posted when, or if, it decides to break.

Re: Valve relief pockets as gas ports??? [Re: 1976 Aspen] #189590 01/12/09 10:12 PM 01/12/09 10:12 PM
A Anonymous Unregistered
Anonymous Unregistered A	maybe i'm just seeing a reflection or something. it looks like 3 different holes. 4943932-piston.jpg (68 downloads)

Re: Valve relief pockets as gas ports??? #189591 01/12/09 10:14 PM 01/12/09 10:14 PM
Joined: Sep 2007 Posts: 238 Roseau, MN 1976 Aspen OP enthusiast
1976 Aspen OP enthusiast Joined: Sep 2007 Posts: 238 Roseau, MN	DRAM, you're seeing a reflection. The only hole is on the intake relief furthest to the left. The others are just camera glare. Whatcha think about it now???

Re: Valve relief pockets as gas ports??? [Re: 1976 Aspen] #189592 01/12/09 10:22 PM 01/12/09 10:22 PM
A Anonymous Unregistered
Anonymous Unregistered A	Quote: DRAM, you're seeing a reflection. The only hole is on the intake relief furthest to the left. The others are just camera glare. Whatcha think about it now??? what's the depth of the valve pocket and were they shelf stock CP pistons you started with?

Re: Valve relief pockets as gas ports??? #189593 01/12/09 10:27 PM 01/12/09 10:27 PM
Joined: Sep 2007 Posts: 238 Roseau, MN 1976 Aspen OP enthusiast
1976 Aspen OP enthusiast Joined: Sep 2007 Posts: 238 Roseau, MN	The pocket depth from the top of the piston to the deepest part of the pocket??? No, they were custom CP's ordered from SDSS when he did my stroker kit last winter.

Re: Valve relief pockets as gas ports??? [Re: 1976 Aspen] #189594 01/12/09 10:29 PM 01/12/09 10:29 PM
A Anonymous Unregistered
Anonymous Unregistered A	Quote: The pocket depth from the top of the piston to the deepest part of the pocket??? yes, and if you know, how deep were they before they were cut?

Re: Valve relief pockets as gas ports??? #189595 01/12/09 11:15 PM 01/12/09 11:15 PM
Joined: Sep 2007 Posts: 238 Roseau, MN 1976 Aspen OP enthusiast
1976 Aspen OP enthusiast Joined: Sep 2007 Posts: 238 Roseau, MN	They're about .250 deep now and they were like .190 deep I think.

Re: Valve relief pockets as gas ports??? [Re: 1976 Aspen] #189596 01/13/09 12:43 AM 01/13/09 12:43 AM
A Anonymous Unregistered
Anonymous Unregistered A	i'm not 100% positive but i think their std. smallblock valve reliefs are something like .230 intake and .190 exhaust. being a custom set they might have been deeper than that already. to answer your other question, no, i still wouldn't run them. that's a very large hole. eventually the ring gap will line up with that hole and may actually get stuck there due to the pressure escaping. it's not anything like a normal gas port. good luck with them, i hope it doesn't cost you a motor down the road. no doubt it'll run, for how long is the question.

Re: Valve relief pockets as gas ports??? #189597 01/13/09 09:43 AM 01/13/09 09:43 AM
Joined: Jan 2003 Posts: 8,547 State College, PA RyanJ moparts member
RyanJ moparts member Joined: Jan 2003 Posts: 8,547 State College, PA	My CP spec sheet shows them being .280" intake .250" exhaust when I had them made

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