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

PTV clearance question...

Thread Tools
 
Search this Thread
 
Old 05-14-2006, 08:12 PM
  #1  
TECH Addict
Thread Starter
iTrader: (10)
 
SSpdDmon's Avatar
 
Join Date: Jun 2004
Location: Commerce Twp, MI
Posts: 2,918
Likes: 0
Received 0 Likes on 0 Posts

Default PTV clearance question...

Didn't know if anyone on here has some good knowledge about PTV on an LS1. Friend of mine has a '99 and just bought a TSP Torquer cam (232/234 .595/.598 112LSA) along with a set of Stage 2 LS6 heads milled slightly so that they have 63cc chambers. He's been running a set of Comp Cams Pro-Magnum 1.75 rocker arms. If he transfers those rockers to the new heads, his new cam specs will be more like 232/234 .613/.616. Does anyone know if he'll be able to run those rockers with his new setup or will he have to go back to a 1.7 ratio?

Last edited by SSpdDmon; 05-14-2006 at 10:04 PM.
Old 05-14-2006, 08:16 PM
  #2  
TECH Resident
iTrader: (11)
 
ThirdGenLS1's Avatar
 
Join Date: Jul 2004
Location: Boston
Posts: 987
Likes: 0
Received 0 Likes on 0 Posts

Default

lift has little to do with PTV, its mostly about valve events and duration. His best bet is to just get a checker spring, dial indicator, and measure it him self.

Justin
Old 05-14-2006, 08:19 PM
  #3  
TECH Senior Member
iTrader: (23)
 
brad8266's Avatar
 
Join Date: Aug 2005
Location: Watertown, NY
Posts: 8,797
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by ThirdGenLS1
lift has little to do with PTV, its mostly about valve events and duration. His best bet is to just get a checker spring, dial indicator, and measure it him self.

Justin
PTV issues are more coorelated to cam duration with lift combined. You could have .6 lift with no issue as long as this lift occurs when the piston is at the bottom of the bore, but if it has .5 lift when the piston is almost at top it could crash. Duration will determine the valve events.
Old 05-14-2006, 10:02 PM
  #4  
TECH Addict
Thread Starter
iTrader: (10)
 
SSpdDmon's Avatar
 
Join Date: Jun 2004
Location: Commerce Twp, MI
Posts: 2,918
Likes: 0
Received 0 Likes on 0 Posts

Default

Ok...so maybe I asked the question wrong. But, that still has nothing to do with whether or not the setup will work. Does anyone know if this setup will work with 1.75 rockers without having to go through the whole buying new tools or puddy to check clearance? If not, that's fine....but don't sit there and belittle someone for making a small mistake in his question.
Old 05-14-2006, 10:04 PM
  #5  
TECH Resident
iTrader: (11)
 
ThirdGenLS1's Avatar
 
Join Date: Jul 2004
Location: Boston
Posts: 987
Likes: 0
Received 0 Likes on 0 Posts

Default

the thing is i dont think anyone is going to be able to give you a 100% answere on this. It wil be tight, as to how tight you wont know unless you check it.
Old 05-14-2006, 10:31 PM
  #6  
TECH Senior Member
iTrader: (23)
 
brad8266's Avatar
 
Join Date: Aug 2005
Location: Watertown, NY
Posts: 8,797
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by SSpdDmon
Ok...so maybe I asked the question wrong. But, that still has nothing to do with whether or not the setup will work. Does anyone know if this setup will work with 1.75 rockers without having to go through the whole buying new tools or puddy to check clearance? If not, that's fine....but don't sit there and belittle someone for making a small mistake in his question.
Nobody belittled you man, what made you think that? We just told you how it is.
Old 05-15-2006, 01:52 AM
  #7  
Banned
iTrader: (7)
 
Quik's Avatar
 
Join Date: Oct 2003
Location: Pittsburgh!!!!!!!! Pa
Posts: 4,893
Likes: 0
Received 0 Likes on 0 Posts
Default

tv2 112 243 castings on a LQ9 which has flat top pistons, 6.0 MLS gasket and no PTV issues. motor runs fine

hopefully that gives an idea
Old 05-15-2006, 04:44 AM
  #8  
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 SSpdDmon
Didn't know if anyone on here has some good knowledge about PTV on an LS1. Friend of mine has a '99 and just bought a TSP Torquer cam (232/234 .595/.598 112LSA) along with a set of Stage 2 LS6 heads milled slightly so that they have 63cc chambers. He's been running a set of Comp Cams Pro-Magnum 1.75 rocker arms. If he transfers those rockers to the new heads, his new cam specs will be more like 232/234 .613/.616. Does anyone know if he'll be able to run those rockers with his new setup or will he have to go back to a 1.7 ratio?
If you run stock gasket, you should be fine. Just make sure that you preload the lifters right.
And checking should be mandatory.
Old 05-16-2006, 08:40 PM
  #9  
Teching In
iTrader: (4)
 
JS99Z's Avatar
 
Join Date: Sep 2005
Location: Dewitt, Michigan
Posts: 25
Likes: 0
Received 0 Likes on 0 Posts

Default

I was told since I have the comp r lifters if I want to go back to 1.7 ratio I can't use the stock rockers, they have to be adjustable rockers. Is this true?

By the way this is my never ending project SSpdDmon's
talking about in this post.
Old 06-16-2006, 03:10 PM
  #10  
On The Tree
iTrader: (2)
 
ls1z01's Avatar
 
Join Date: Mar 2002
Location: California, Monterey Park
Posts: 195
Received 0 Likes on 0 Posts

Default

Originally Posted by PREDATOR-Z
If you run stock gasket, you should be fine. Just make sure that you preload the lifters right.
And checking should be mandatory.
How thick is the stock head gasket?
Old 06-16-2006, 04:36 PM
  #11  
TECH Fanatic
iTrader: (8)
 
Xtnct00WS6's Avatar
 
Join Date: Jan 2005
Location: Sterling VA
Posts: 1,429
Likes: 0
Received 2 Likes on 2 Posts

Default

Originally Posted by ls1z01
How thick is the stock head gasket?
I've seen different numbers ranging from 55 thousands to 60 thousands
Old 06-16-2006, 04:42 PM
  #12  
TECH Resident
iTrader: (11)
 
ThirdGenLS1's Avatar
 
Join Date: Jul 2004
Location: Boston
Posts: 987
Likes: 0
Received 0 Likes on 0 Posts

Default

mine was 55 when i measusred it




All times are GMT -5. The time now is 01:03 AM.