Notices
GM Engine & Exhaust Performance EFI | GEN I/GEN II/GEN III/GEN IV Engines |Small Block | Big Block |

vortec 5.7

Thread Tools
 
Search this Thread
 
Old 12-24-2008, 04:16 PM
  #11  
On The Tree
 
mds2004's Avatar
 
Join Date: Jul 2006
Location: Bakersfield, CA
Posts: 164
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by blueflamed03
just remeber with a cam over .440 lift, you'll need to have the heads re-done to accomodate the added lift.
I believe its .480 but with new locks and retainers that are +.50 you can use up to .530. But yes running that high would still be best to make room for more by pulling the heads. With doing so you you can pretty much run whatever. I know my cam is higher but i cant remember off the top of my head but I think its in my sig.
Old 12-25-2008, 01:52 AM
  #12  
Truck Sponsor
iTrader: (12)
 
Wheatley's Avatar
 
Join Date: Apr 2003
Location: Sealy/Katy TX
Posts: 3,286
Likes: 0
Received 2 Likes on 2 Posts
Default

That is false
With the correct springs,retainers and locks you can run lift most would think is not possible on the vortec 350
I had a cam in my 97 L31 that had a 493/502 lift and the heads never even came off the block
It can be done with the right setup
The thing is most do not even think it is possible on stock heads
a buddy told me it can be done
He was right
Originally Posted by blueflamed03
just remeber with a cam over .440 lift, you'll need to have the heads re-done to accomodate the added lift.
Old 12-25-2008, 02:03 AM
  #13  
On The Tree
 
mds2004's Avatar
 
Join Date: Jul 2006
Location: Bakersfield, CA
Posts: 164
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by Wheatley
That is false
With the correct springs,retainers and locks you can run lift most would think is not possible on the vortec 350
I had a cam in my 97 L31 that had a 493/502 lift and the heads never even came off the block
It can be done with the right setup
The thing is most do not even think it is possible on stock heads
a buddy told me it can be done
He was right
Yup its .530 max with the correct setup supposedly. I ran my old cam that was around there before I had the heads worked.
Old 12-25-2008, 11:58 AM
  #14  
TECH Fanatic
iTrader: (1)
 
1Bear's Avatar
 
Join Date: Aug 2006
Location: Jones Creek, Texas
Posts: 1,410
Likes: 0
Received 8 Likes on 8 Posts
Default

While it is possible to obtain the necessary clearance to run more lift if you use Comp 915 Beehives or equivalent, that are designed for LS1's at an installed height of 1.800", instead of the factory SBC height of 1.750" you can obviously run more lift without the retainer hitting the valve guide or seal, but you will need a few parts to make it work.

To run LS1 style Beehives in a SBC designed with 11/32" valve stems, you will need to use a hybrid retainer. Comp makes such a retainer Part # 787-16. Also to get the installed height of 1.800" you will need a +0.50" steel lock/keeper and Crane makes just a jewel: Part # 99095-1, coded Yellow.

What ever you do though, don't attempt to install the +0.50" keepers on valve springs designed for a stock installed height of 1.750" or you will loose the required spring pressure. Also don't assume that because we were able to get that much clearance on Charlie's motor that you can too. In each case clearance will need to be verified.

Note: Comp's 915 & 918 springs will fit the spring pocket in a SBC without machining to the head and will also have the necessary clearance around the large valve guide that the Vortec head uses. For people who will get the idea to just use LS6 springs as a cost saving measure, while they will fit the spring pocket, they may not fit around the valve guide. The LS6 spring has a slightly smaller I.D. than the Comp's.
Old 12-25-2008, 01:23 PM
  #15  
Truck Sponsor
iTrader: (12)
 
Wheatley's Avatar
 
Join Date: Apr 2003
Location: Sealy/Katy TX
Posts: 3,286
Likes: 0
Received 2 Likes on 2 Posts
Default

there he is
Originally Posted by 1Bear
While it is possible to obtain the necessary clearance to run more lift if you use Comp 915 Beehives or equivalent, that are designed for LS1's at an installed height of 1.800", instead of the factory SBC height of 1.750" you can obviously run more lift without the retainer hitting the valve guide or seal, but you will need a few parts to make it work.

To run LS1 style Beehives in a SBC designed with 11/32" valve stems, you will need to use a hybrid retainer. Comp makes such a retainer Part # 787-16. Also to get the installed height of 1.800" you will need a +0.50" steel lock/keeper and Crane makes just a jewel: Part # 99095-1, coded Yellow.

What ever you do though, don't attempt to install the +0.50" keepers on valve springs designed for a stock installed height of 1.750" or you will loose the required spring pressure. Also don't assume that because we were able to get that much clearance on Charlie's motor that you can too. In each case clearance will need to be verified.

Note: Comp's 915 & 918 springs will fit the spring pocket in a SBC without machining to the head and will also have the necessary clearance around the large valve guide that the Vortec head uses. For people who will get the idea to just use LS6 springs as a cost saving measure, while they will fit the spring pocket, they may not fit around the valve guide. The LS6 spring has a slightly smaller I.D. than the Comp's.
Old 12-25-2008, 02:31 PM
  #16  
9 Second Truck Club
iTrader: (16)
 
stock48's Avatar
 
Join Date: Sep 2006
Location: Colorado Springs, Co/ Central, Ca
Posts: 3,655
Received 5 Likes on 5 Posts
Default

Also something to look at is the pressed in rocker studs, they can pull out when open spring psi gets near 300lbs.
Old 12-29-2008, 10:17 AM
  #17  
TECH Enthusiast
iTrader: (1)
 
blueflamed03's Avatar
 
Join Date: Jul 2008
Location: Oklahoma
Posts: 647
Likes: 0
Received 1 Like on 1 Post
Default

dang good info on spring setup.....thanks!
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
gaps
GMT 800 & Older GM General Discussion
10
10-15-2015 02:53 PM
Big_pimie
New Members
0
09-22-2015 09:07 PM
FormulaZR
GM Engine & Exhaust Performance
1
09-14-2015 05:23 PM
2plus2
GMT 900 Trucks General Discussion
4
09-13-2015 07:17 PM



Quick Reply: vortec 5.7



All times are GMT -5. The time now is 02:28 AM.