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  #21  
Old 12-20-2015, 08:28 PM
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Originally Posted by glidein wide
John said I need valve relief some why would he say if I bought new pistons with relief it wouldn't help ?
So it seems the trouble with John's posts is with his cell phone key pad use ... and there was me thinking he was TUI-ing (typing under the influence).

Sometimes you have to decipher the mystery in his utterances. He's like one of those Zen masters. You have to work out what the right question is, and ask it, to understand his answer.

What exactly is $75 for ... 2 x new OEM 'pistons and rings' sets?

If I were you'd I'd go bargain hunting. It's a good time to buy. For a little extra you might get some higher compression ones off some dusty shelf ... those would help performance. For a little patience and effort, you might get cheap NOS or stock takeoffs. Depending on the miles, it might be worth a hone to the next sized up as, strictly speaking, you should be careful to match your pistons to your cylinders.

If you are not going to hone - which is more expense - I'd just consider sticking with your old pistons, and having them cut, as they have worn to fit your cylinders and vice versa.

What do you think, John? Is there meat enough to cut a relief in them?
 
  #22  
Old 12-20-2015, 08:55 PM
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yes on the piston deck for cutting a valve pocket and any good shop has a bridgeport and can provide this service if you want to go that way

you said you have hastings rings and they are moly coated ( top ring only ) and its what all the real shops use
 
  #23  
Old 12-20-2015, 09:03 PM
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Well, there's your (cheap and efficient) answer, Glide.

Send your old pistons to John with some beer tokens attached. He has a good reputation for some fast turn around and decent treatment of forum members.

See note above about how to mark them.

Save your money for the *next* time you take your top end apart, and go for a first over size using 10.5:1 pistons.
 
  #24  
Old 12-20-2015, 09:05 PM
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for got - you cant just mike the cam and come up with the numbers

take the cam in 2 dead or live centers - from the bottom ( the base circle ) put a dial gague on it and rotate it around you want ( lobe lift ) then take that number lets say .305 and times it against the rocker arm ratio - 1.625 = 0.495625 < an ev 27 - now if you have the original pistons you valve installed height is probably 1,850 atthat standing height on the valve in the valve seat .305 lobe lift the piston will make contact at 15* BTDC with out a valve pocket
 
  #25  
Old 12-20-2015, 09:27 PM
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Originally Posted by neo-con-bigot
So it seems the trouble with John's posts is with his cell phone key pad use ... and there was me thinking he was TUI-ing (typing under the influence).

Sometimes you have to decipher the mystery in his utterances. He's like one of those Zen masters. You have to work out what the right question is, and ask it, to understand his answer.

What exactly is $75 for ... 2 x new OEM 'pistons and rings' sets?

If I were you'd I'd go bargain hunting. It's a good time to buy. For a little extra you might get some higher compression ones off some dusty shelf ... those would help performance. For a little patience and effort, you might get cheap NOS or stock takeoffs. Depending on the miles, it might be worth a hone to the next sized up as, strictly speaking, you should be careful to match your pistons to your cylinders.

If you are not going to hone - which is more expense - I'd just consider sticking with your old pistons, and having them cut, as they have worn to fit your cylinders and vice versa.

What do you think, John? Is there meat enough to cut a relief in them?
Yeah,$30. Each for stock replacement pistons without rings in my book(with relief)
And yes the jugs are being honed at my local Indy, he has the pistons also to properly size the rings and such,and a valve job on the heads.
 
  #26  
Old 12-20-2015, 09:31 PM
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Originally Posted by neo-con-bigot
Well, there's your (cheap and efficient) answer, Glide.

Send your old pistons to John with some beer tokens attached. He has a good reputation for some fast turn around and decent treatment of forum members.

See note above about how to mark them.

Save your money for the *next* time you take your top end apart, and go for a first over size using 10.5:1 pistons.
Not looking for big compression either, I still want to be able to kick start the thing.
I do have a three axis Bridgeport at my shop but can't be bothered with figuring out how and where to cut the relief, John may have something for me.
 

Last edited by glidein wide; 12-20-2015 at 09:35 PM.
  #27  
Old 12-20-2015, 09:32 PM
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Originally Posted by glidein wide
Yeah,$30. Each for stock replacement pistons without rings in my book(with relief)
And yes the jugs are being honed at my local Indy, he has the pistons also to properly size the rings and such,and a valve job on the heads.
I put my 27 in myself and about 30k later I found that the stock valve springs were hitting the inside of the rocker boxes.
I suggest you go with beehive valve springs to avoid this possibility.
 
  #28  
Old 12-20-2015, 09:41 PM
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Originally Posted by texashillcountry
I put my 27 in myself and about 30k later I found that the stock valve springs were hitting the inside of the rocker boxes.
I suggest you go with beehive valve springs to avoid this possibility.
Well that sucks, so much for being a bolt in cam,even Andrew site says bolt in cam.
 
  #29  
Old 12-20-2015, 09:48 PM
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Originally Posted by glidein wide
Well that sucks, so much for being a bolt in cam,even Andrew site says bolt in cam.
As I said I ran it for 30k with no known issues.
I didn't know or even suspect that the springs where hitting the inside of my rocker boxes until I took it apart to upgrade compression and have the heads ported and flowed.
I can't guarantee you that the cam was at fault but that is what I think caused it.
You would have to get someone smarter than me (very easy to do around here) to chime in.
 
  #30  
Old 12-20-2015, 10:11 PM
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Originally Posted by texashillcountry
As I said I ran it for 30k with no known issues.
I didn't know or even suspect that the springs where hitting the inside of my rocker boxes until I took it apart to upgrade compression and have the heads ported and flowed.
I can't guarantee you that the cam was at fault but that is what I think caused it.
You would have to get someone smarter than me (very easy to do around here) to chime in.
I hear what your saying Texas, a topic like this has to deal with absolute facts and not opinions so when someone tells me what they recommend, I hope it's from experience and not a guess or experiment.
Now I'm curious how many people were told "just slap it in and ride" and destroyed there engine at start up.....
 


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