Generation III Internal Engine 1997-2006 LS1 | LS6
Sponsored by:
Sponsored by:

Push Rod Length

Thread Tools
 
Search this Thread
 
Old 04-19-2006, 10:24 PM
  #1  
Staging Lane
Thread Starter
iTrader: (2)
 
50chevy's Avatar
 
Join Date: Dec 2005
Location: San Antonio, Tx
Posts: 93
Likes: 0
Received 0 Likes on 0 Posts
Default Push Rod Length

I just installed a LPE-gt2-5 222/222 .566/.566" on a 112lsa and i do not know what the base circle is of the cam to see how it compares to a stock cam. I put the stock rockers and pushrods back in the engine and spun it over to make sure there were no piston to valve problems. The sweep of the rockers looks to be alright on the valve tip but i'm not sure if the stock pushrod length is acceptable and how relible it is?
Old 04-19-2006, 10:33 PM
  #2  
11 Second Club
iTrader: (14)
 
SUX2BU's Avatar
 
Join Date: Apr 2002
Location: DFW, TX
Posts: 3,267
Likes: 0
Received 1 Like on 1 Post

Default

Originally Posted by 50chevy
I just installed a LPE-gt2-5 222/222 .566/.566" on a 112lsa and i do not know what the base circle is of the cam to see how it compares to a stock cam. I put the stock rockers and pushrods back in the engine and spun it over to make sure there were no piston to valve problems. The sweep of the rockers looks to be alright on the valve tip but i'm not sure if the stock pushrod length is acceptable and how relible it is?
You should be fine. but if you want it to be exact get a pushrod checker. Stock heads?
Old 04-19-2006, 10:35 PM
  #3  
Staging Lane
Thread Starter
iTrader: (2)
 
50chevy's Avatar
 
Join Date: Dec 2005
Location: San Antonio, Tx
Posts: 93
Likes: 0
Received 0 Likes on 0 Posts
Default

Ya, they are the stock heads #706 on a 2001 5.3L
Old 04-19-2006, 10:46 PM
  #4  
11 Second Club
iTrader: (14)
 
SUX2BU's Avatar
 
Join Date: Apr 2002
Location: DFW, TX
Posts: 3,267
Likes: 0
Received 1 Like on 1 Post

Default

Originally Posted by 50chevy
Ya, they are the stock heads #706 on a 2001 5.3L
Yeah most aftermaret cams are .100 smaller on the base circle. so to keep the stock lifter preload you would need a .050 longer pushrod. but many people have run stock length pushrods with aftermarket cams for years with no problems. if you want it to be perfect get some 7.425 PR. they actually mic out to 7.440 so you would be .010 away from stock preload.
Old 04-20-2006, 01:36 AM
  #5  
ЯєŧąяĐ Єl¡m¡иąŧøя ™
iTrader: (18)
 
orangeapeel's Avatar
 
Join Date: Nov 2004
Location: Justin, TX
Posts: 16,083
Likes: 0
Received 4 Likes on 4 Posts

Default

Yeah, I would suggest the 7.425 for a quieter more precise setup.
Old 04-20-2006, 02:09 AM
  #6  
TECH Fanatic
iTrader: (1)
 
ssheets's Avatar
 
Join Date: Nov 2003
Location: Gardnerville, NV.
Posts: 1,037
Likes: 0
Received 0 Likes on 0 Posts

Default

So let's say you were running an F14 cam and milled the heads .007 and then dropped in a 43" head gasket...would 7.400 PRs work?

Looks like my base circles are 1.450. The above configuration would put the valvetrain .018" closer to the lobes.
Old 04-20-2006, 02:20 AM
  #7  
ЯєŧąяĐ Єl¡m¡иąŧøя ™
iTrader: (18)
 
orangeapeel's Avatar
 
Join Date: Nov 2004
Location: Justin, TX
Posts: 16,083
Likes: 0
Received 4 Likes on 4 Posts

Default

Would that be an MLS or cometic?
Old 04-20-2006, 02:23 AM
  #8  
TECH Fanatic
iTrader: (1)
 
ssheets's Avatar
 
Join Date: Nov 2003
Location: Gardnerville, NV.
Posts: 1,037
Likes: 0
Received 0 Likes on 0 Posts

Default

Originally Posted by orangeapeel
Would that be an MLS or cometic?
Don't have it yet...should I be asking you a different question?

I have an OEM MLS for measuring PtoV and I'm hoping I'll be able to get away with the .043. I was looking at SCE Titans as I can drive to Summit Racing and pick them up. I've heard Cometics have looooooooong lead times.
What about Fel-Pro or anyone else?

(Sorry to jack the push rod post)
Old 04-20-2006, 02:30 AM
  #9  
ЯєŧąяĐ Єl¡m¡иąŧøя ™
iTrader: (18)
 
orangeapeel's Avatar
 
Join Date: Nov 2004
Location: Justin, TX
Posts: 16,083
Likes: 0
Received 4 Likes on 4 Posts

Default

Im not a fan of the FEL Pro personally. I have used MLS gaskets everytime and they have worked great. I have seen some pansy setups blow head gaskets that were fel-pro'd...
Plus I believe that this thread is answered for the most part.
Old 04-20-2006, 10:50 AM
  #10  
TECH Fanatic
iTrader: (1)
 
ssheets's Avatar
 
Join Date: Nov 2003
Location: Gardnerville, NV.
Posts: 1,037
Likes: 0
Received 0 Likes on 0 Posts

Default

Originally Posted by orangeapeel
Im not a fan of the FEL Pro personally. I have used MLS gaskets everytime and they have worked great. I have seen some pansy setups blow head gaskets that were fel-pro'd...
Plus I believe that this thread is answered for the most part.
I'll ask on a seperate post about SCE Titans
Old 04-20-2006, 12:45 PM
  #11  
TECH Senior Member
 
PREDATOR-Z's Avatar
 
Join Date: Mar 2004
Location: BFE
Posts: 14,620
Likes: 0
Received 16 Likes on 16 Posts

Default

Originally Posted by SUX2BU
Yeah most aftermaret cams are .100 smaller on the base circle. so to keep the stock lifter preload you would need a .050 longer pushrod. but many people have run stock length pushrods with aftermarket cams for years with no problems. if you want it to be perfect get some 7.425 PR. they actually mic out to 7.440 so you would be .010 away from stock preload.
Not quite,
It all depends on the lobe used and the lifts.
Best way is to measure the Base Circle and go from there.



Quick Reply: Push Rod Length



All times are GMT -5. The time now is 08:21 AM.