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

Quick PTV clearance question

Thread Tools
 
Search this Thread
 
Old 05-02-2010, 06:43 PM
  #1  
TECH Enthusiast
Thread Starter
iTrader: (21)
 
Zach79Z's Avatar
 
Join Date: Feb 2007
Location: Ringgold, GA
Posts: 614
Likes: 0
Received 0 Likes on 0 Posts

Default Quick PTV clearance question

curious to get everybodys opinion. we was puttin togethor my ls1 and we used the playdough meathod to check ptv clearance and it measured out to be 43 thousandths and 50 thousandths. would this be a safe to run? its a stock ls1 with portd 241s and custom grind cam.
Old 05-02-2010, 07:46 PM
  #2  
TECH Senior Member
iTrader: (4)
 
vettenuts's Avatar
 
Join Date: Jul 2004
Location: Little Rhody
Posts: 8,092
Likes: 0
Received 9 Likes on 9 Posts

Default

How big is the cam? I personally wouldn't run it that tight. The clay method is also very inaccurate and I would double check with a dial indicator.
Old 05-02-2010, 09:30 PM
  #3  
On The Tree
iTrader: (3)
 
Bad Notch's Avatar
 
Join Date: May 2007
Posts: 121
Likes: 0
Received 0 Likes on 0 Posts
Default

Im in the exact same boat, its too tight. Break out the fly cutting toolz
Old 05-02-2010, 10:04 PM
  #4  
TECH Enthusiast
Thread Starter
iTrader: (21)
 
Zach79Z's Avatar
 
Join Date: Feb 2007
Location: Ringgold, GA
Posts: 614
Likes: 0
Received 0 Likes on 0 Posts

Default

the cam is a 231 239 .617 .621 @ 111+4 on LSL lobes. I really dont wana flycut the pistons
Old 05-04-2010, 04:58 AM
  #5  
TECH Resident
iTrader: (14)
 
Squirts11's Avatar
 
Join Date: Sep 2009
Location: OKC, OK
Posts: 898
Received 4 Likes on 2 Posts

Default

Originally Posted by Zach79Z
the cam is a 231 239 .617 .621 @ 111+4 on LSL lobes. I really dont wana flycut the pistons
The recommended clearances are 080/.100 for the intake/exhaust. You seem to be quite a bit below that. If you were around .070/.090, you could prob just run a bit thicker gasket and be fine, but I doubt the clearances you measured (if accurate via the clay method) are safe gaps.
Old 05-04-2010, 06:53 AM
  #6  
TECH Enthusiast
Thread Starter
iTrader: (21)
 
Zach79Z's Avatar
 
Join Date: Feb 2007
Location: Ringgold, GA
Posts: 614
Likes: 0
Received 0 Likes on 0 Posts

Default

was re checking everything last night and actually swapped stock pushrods in and the clearanc was 63 thousadnths and 65 thousandths. Measured the 7.425 pushrods i had and they measured 7.445. Im thinking the extra lil 20 thousandths longer pushrod is whats throwing it off so bad.
Old 05-04-2010, 11:03 AM
  #7  
TECH Senior Member
iTrader: (4)
 
vettenuts's Avatar
 
Join Date: Jul 2004
Location: Little Rhody
Posts: 8,092
Likes: 0
Received 9 Likes on 9 Posts

Default

If the pushrod length makes a difference in the measurement, you are not measuring correctly. Exactly how are you doing this? Do you have solid lifters? Based on what you have found, my guess is all your numbers are inaccurate.




All times are GMT -5. The time now is 08:15 AM.