Generation IV Internal Engine 2005-2014 LS2 | LS3 | LS7 | L92 | LS9

.631/.644" cam - PTV issues?

Thread Tools
 
Search this Thread
 
Old 03-07-2008 | 12:35 PM
  #1  
FastBlackTA's Avatar
Thread Starter
8 Second Club
iTrader: (7)
 
Joined: Dec 2002
Posts: 1,086
Likes: 0
From: Maryland
Default .631/.644" cam - PTV issues?

I am purchasing a cam for my LS2 motor with 4cc valve relief pistons. .631/.644 lift. Stock stroke.

I am definately going to check my PTV clearance, but anybody out there forsee any issues?
Old 03-07-2008 | 12:40 PM
  #2  
LSGunZ28's Avatar
11 Second Club

iTrader: (8)
 
Joined: Aug 2005
Posts: 2,451
Likes: 0
From: Pasadena, CA
Default

Originally Posted by FastBlackTA
I am purchasing a cam for my LS2 motor with 4cc valve relief pistons. .631/.644 lift. Stock stroke.

I am definately going to check my PTV clearance, but anybody out there forsee any issues?
Im pretty sure we wanna know your duration #s
Old 03-07-2008 | 12:43 PM
  #3  
FastBlackTA's Avatar
Thread Starter
8 Second Club
iTrader: (7)
 
Joined: Dec 2002
Posts: 1,086
Likes: 0
From: Maryland
Default

215/231 .631/.644 cam on a 118 LSA

sorry, forgot to post all specs
Old 03-07-2008 | 12:45 PM
  #4  
JPH's Avatar
JPH
TECH Junkie

iTrader: (2)
 
Joined: Jan 2006
Posts: 3,776
Likes: 0
From: Fort Wayne, IN
Default

Originally Posted by FastBlackTA
215/231 .631/.644 cam on a 118 LSA

sorry, forgot to post all specs
yeah, that will clear by a mile.
Old 03-07-2008 | 12:46 PM
  #5  
Patrick G's Avatar
LS1 Tech Administrator
iTrader: (14)
 
Joined: Nov 2001
Posts: 8,245
Likes: 32
From: Victoria, TX
Default

Your valve are a maximum lift when the piston is all the way down the cylinder bore. It's during the overlap cycle when you run into piston to valve clearance. Duration is what gets you, not lift. We'll need to know a lot more about your setup. What size heads, what size valves you're running, what size combustion chambers, how much the heads have been milled, and how thick of a head gasket. Give us those details and the duration, LSA and installed intake centerline and you'll get a more more educated answer.

Hey nobody said it was going to be an easy answer.
__________________

2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.

Old 03-07-2008 | 12:58 PM
  #6  
FastBlackTA's Avatar
Thread Starter
8 Second Club
iTrader: (7)
 
Joined: Dec 2002
Posts: 1,086
Likes: 0
From: Maryland
Default

215/231 .631/.644 cam on a 118 LSA

Thanks
Old 03-07-2008 | 12:59 PM
  #7  
FastBlackTA's Avatar
Thread Starter
8 Second Club
iTrader: (7)
 
Joined: Dec 2002
Posts: 1,086
Likes: 0
From: Maryland
Default

stock cubes, stock heads, stock valves, 4cc valve relief pistons
Old 03-07-2008 | 02:11 PM
  #8  
Jeff@TotalPerformanceEng's Avatar
FormerVendor
iTrader: (6)
 
Joined: Mar 2006
Posts: 520
Likes: 0
From: "Sin City" Las Vegas
Default

What springs? (No relation to PTV)
Old 03-07-2008 | 02:43 PM
  #9  
FastBlackTA's Avatar
Thread Starter
8 Second Club
iTrader: (7)
 
Joined: Dec 2002
Posts: 1,086
Likes: 0
From: Maryland
Default

patriot duals
Old 03-07-2008 | 08:16 PM
  #10  
Jeff@TotalPerformanceEng's Avatar
FormerVendor
iTrader: (6)
 
Joined: Mar 2006
Posts: 520
Likes: 0
From: "Sin City" Las Vegas
Default

Your leaving yourself NO room for error. If their the golds, then their max lift is .650?

If your running an aggressive lobe profile, and that little margin for error, your askin for problems.

Just my .02
Originally Posted by FastBlackTA
patriot duals
Old 03-07-2008 | 09:03 PM
  #11  
Alvin's Avatar
TECH Enthusiast
iTrader: (2)
 
Joined: Dec 2005
Posts: 718
Likes: 0
Default

You'll be fine. I ran a similar speced cam in a stock LS2 but with 2 degrees tigher LSA and I want to say I had something like .084 on the intake and .116 on the exhaust.
Old 03-07-2008 | 09:07 PM
  #12  
edcmat-l1's Avatar
Banned
iTrader: (10)
 
Joined: Jul 2006
Posts: 4,782
Likes: 4
From: Va Beach
Default

Originally Posted by Alvin
You'll be fine. I ran a similar speced cam in a stock LS2 but with 2 degrees tigher LSA and I want to say I had something like .084 on the intake and .116 on the exhaust.
yeah but hes cuttin it close on the spring clearance to coil bind.
Old 03-08-2008 | 09:14 AM
  #13  
FastBlackTA's Avatar
Thread Starter
8 Second Club
iTrader: (7)
 
Joined: Dec 2002
Posts: 1,086
Likes: 0
From: Maryland
Default

Lingenfelter claims that they work well with this application....I should be fine spring-wise, I just wanted to check to ensure I wouldn't have any PTV issues.
Old 03-08-2008 | 12:46 PM
  #14  
blackz93's Avatar
TECH Fanatic
iTrader: (2)
 
Joined: May 2003
Posts: 1,661
Likes: 1
From: nc
Default

Originally Posted by edcmat-l1
yeah but hes cuttin it close on the spring clearance to coil bind.

He asked about PTV clearance, not coil bind.
Old 03-08-2008 | 12:49 PM
  #15  
Tom@SpeedInc's Avatar
Banned
iTrader: (5)
 
Joined: Apr 2003
Posts: 1,890
Likes: 0
From: Chicago
Default

Originally Posted by FastBlackTA
Lingenfelter claims that they work well with this application....I should be fine spring-wise, I just wanted to check to ensure I wouldn't have any PTV issues.
They are right, we've had customers come in for dyno tune with this cam and made numbers we would expect of a cam with more duration.

I've seen a graph where someone swapped this cam for some godzilla cam spec'd by one of the people known for custom cams around the forums, which only lead to +5 peak hp and -10hp below peak in an LS2.



Quick Reply: .631/.644" cam - PTV issues?



All times are GMT -5. The time now is 09:09 AM.