Just how bad is..... ***updated***
#1130943
12/10/11 02:52 AM
12/10/11 02:52 AM
|
Joined: Nov 2004
Posts: 8,094 Sunnyvale, CA
Jeepmon
OP
master
|
OP
master
Joined: Nov 2004
Posts: 8,094
Sunnyvale, CA
|
.009 to .010 piston to wall clearance??
Is it bad enough to scrap the pistons and buy new ones? or will this just be an inconvenience, noisy build that wont last too long?
I just found out my piston to wall clearance is not very good on my 451 cid, 4.375 bore B1 build, which means if I need new pistons, it will push me over my budget as these are not some off the shelf pistons..
What do you think?
Last edited by Jeepmon; 12/13/11 08:20 PM.
|
|
|
Re: Just how bad is.....
[Re: Chris'sBarracuda]
#1130948
12/10/11 03:20 AM
12/10/11 03:20 AM
|
Joined: Nov 2004
Posts: 8,094 Sunnyvale, CA
Jeepmon
OP
master
|
OP
master
Joined: Nov 2004
Posts: 8,094
Sunnyvale, CA
|
Quote:
Do you have the piston job number.?
Chris..
The pistons are at the machine shop now, so a call on Monday might answer your question.. But I dont recall seeing a part number or job number on there.. The only number I saw was a forging number..
|
|
|
Re: Just how bad is.....
[Re: Thumperdart]
#1130949
12/10/11 03:23 AM
12/10/11 03:23 AM
|
Joined: Nov 2004
Posts: 8,094 Sunnyvale, CA
Jeepmon
OP
master
|
OP
master
Joined: Nov 2004
Posts: 8,094
Sunnyvale, CA
|
Quote:
Mine are only around .007 but Jason Pettis likes to run em a bit looser than manufacture recommendations but .010 on modern piston sounds a bit loose but what do I know............
There has been several that have recommended coating the pistons with a coating that will take up approx .002.. I do know thats an option..
(and from what I hear.. Pettis is the man!!)
|
|
|
Re: Just how bad is.....
[Re: Jeepmon]
#1130950
12/10/11 03:24 AM
12/10/11 03:24 AM
|
Joined: Jul 2004
Posts: 19,318 State of confusion
Thumperdart
I Live Here
|
I Live Here
Joined: Jul 2004
Posts: 19,318
State of confusion
|
That`s definately an option.............
72 Dart 470 n/a BB stroker street car `THUMPER`...Check me out on FB Dominic Thumper for videos and lots of carb pics......760-900-3895.....
|
|
|
Re: Just how bad is.....
[Re: Jeepmon]
#1130951
12/10/11 03:30 AM
12/10/11 03:30 AM
|
Joined: Dec 2006
Posts: 3,667 Arizona
Chris'sBarracuda
master
|
master
Joined: Dec 2006
Posts: 3,667
Arizona
|
Quote:
Quote:
Do you have the piston job number.?
Chris..
The pistons are at the machine shop now, so a call on Monday might answer your question.. But I dont recall seeing a part number or job number on there.. The only number I saw was a forging number..
If you know the manufacturer, call them and ask.
When I was assembling mine I thought there was too much clearance, (.010).. But when I talked to Tom Prock @ Venolia he said that with my piston that .0085-.011 was the tolerance..
So there you have it..
:EDIT: This is for a 4.505 bore B1 Venolia 1.29 CD .043 x.043 x 3/16
Chris..
|
|
|
Re: Just how bad is.....
[Re: Chris'sBarracuda]
#1130953
12/10/11 04:17 PM
12/10/11 04:17 PM
|
Joined: Nov 2004
Posts: 8,094 Sunnyvale, CA
Jeepmon
OP
master
|
OP
master
Joined: Nov 2004
Posts: 8,094
Sunnyvale, CA
|
Quote:
If you know the manufacturer, call them and ask.
When I was assembling mine I thought there was too much clearance, (.010).. But when I talked to Tom Prock @ Venolia he said that with my piston that .0085-.011 was the tolerance..
So there you have it..
:EDIT: This is for a 4.505 bore B1 Venolia 1.29 CD .043 x.043 x 3/16
Chris..
Thats interesting Chris.. I've done quite a bit of reading last night and it seems that the majority of the engine builders strive for no more than .007... This is why I posted my question..
BTW.. These are JE Pistons and I will be calling the machine shop on Monday to see if the pistons are engraved..
|
|
|
Re: Just how bad is.....
[Re: Jeepmon]
#1130957
12/11/11 03:23 PM
12/11/11 03:23 PM
|
Joined: Aug 2003
Posts: 43,218 Bend,OR USA
Cab_Burge
I Win
|
I Win
Joined: Aug 2003
Posts: 43,218
Bend,OR USA
|
Don, the piston clearances are determined by several things, the piston alloy being the main one Get the job number off of the pistons and call them(JE) to get thier recommendations If they need coating try calling Embee CO., 714-546-6907, to see if they will hard anadyse(SP?) your pistons. I had them do a set several years back to restore the skirts on a set of Ross pistons that where in a motor that the lifters tops failed and the debris hurt the clinder walls and piston skirts. That was a long time ago and the owner has squeezed(sprayed NOS) that motor a lot since then and beat the snout out of it on the street for close to 20,000 miles on pump gas and accoding to him the pistons look like new the last time he looked at them EDITED: I forgot to mention that Embee is a goverment certified aircraft parts maker and repair center, good stuff Make sure you tell them, if you decide to use them,that you want the hard anadising coating, just like the top fuelers use
Last edited by Cab_Burge; 12/12/11 12:30 AM.
|
|
|
Re: Just how bad is.....
[Re: 383man]
#1130960
12/11/11 09:20 PM
12/11/11 09:20 PM
|
Joined: Nov 2003
Posts: 6,293 Rock Springs
Bob_Coomer
master
|
master
Joined: Nov 2003
Posts: 6,293
Rock Springs
|
i didnt see anyone ask were it loose at.. is it taper? meaning the top of the cylinder has more wear/taper than the bottom.. Like engines with lots of miles? If its consistent, you could use little bigger bore ring, say .005 or so.. if it's taper it wont matter much... It will run sure... It might slobber and have excess blow by...
[color:"red"]65 Hemi Belvedere coming soon [/color] [color:"#00FF00"]557" Indy engine 1.07 60ft 144mph in the 8th 2100 lbs package [/color]
|
|
|
|
|