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well im bout to pull the votec350 apart. n i want to kno some good cams to put in it by Lingenfelter. or any otehr cams. im puttin all new valves in my heads, and boiring it .30 and such i think. hopefully i wont have to broe much. but all info appreciated.
What year model is the 350?
Ok, your sig says it's a 96.
The stock vortec heads are only good for .470" to .475" lift unless you have machine work or after markert / GMPP aluminum heads.
If you try to use more lift than that you will pinch the oil seals and break the stock springs.
I went with a comp cam (I'll get you the numbers when I get out in the garage).
If you add 1.6 roller rockers like I did, the lift will be too much and you'll pinch and break like I did. This is why I'm installing the LS1 LOL!
The vortec motor will idle rough if you go over .214" on the duration so you would have to install a stall converter and some custom programming beyond a Hypertech or compatible programmer. If you look at the combo in my sig, I was putting out somewhere around 340 to 350 HP without the Nitrous.
whats stock cam lift?
This is the factory cam used in all 1996-2000 Chevy L30 & L31 Vortec truck engines.
Intake lift- .414"
Exhaust Lift- .428"
Intake duration @.050"- 191
Exhaust Duration @ .050" - 196
Lobe Centerline- 111
GM (General Motors) part # 10241264
I'm pretty sure this is the cam I went with since the box has a stock vortec cam in it now. The lift is to the max and the stock springs won't last. I added 1.6 roller rockers and drilled out the pushrod holes another 1/8" for clearance. This added close to .030" lift more. I made it 70,000 miles before one of the springs broke but seals were leaking before that. This cam sure loved the 150 shot of Nitrous! There is a tool made for machining the stock vortec heads to get more lift and get away from coil bind.
Here's the motor, I'm gonna miss her!! :cry:
http://i33.photobucket.com/albums/d7...7/b36d23a5.jpg
Part Number 08-500-8
Engine -9999 Chevrolet
305ci-350ci
8cyl.
Grind Number CS XR258HR-12
Description
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Intake Exhaust
Valve Adjustment 0 0
Gross Valve Lift 0.48 0.488
Duration At 0.006 Tappet Lift 258 264
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Valve Timing At 0.006
Open Close
Intake 21 57
Exhaust 68 16
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These Specs Are For The Cam Installed At 108 Intake CL
Intake Exhaust
Duration At 0.05 206 212
Lobe Lift 0.32 0.325
Lobe Separation 112
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Recommended Valve Springs 986-16
1fastsilverado, you might want to talk to vortec 350 also, I looked at his sig and his cam is pretty well at max lift also. He might be able to tell you if he had any head work done to compensate.
You wont miss it for long, you fall in love with the LS1 quickly.
Thats me and my heads did not have any work done to them with this cam!