today i got finaly took my cam out of my 355 to find the lift and duration, the numbers where scratched off so i brought it to a friend at a machine shop to see what he thought it was, he said its definitly a lot bigger than stock cam hes taking a 350 apart now and will find the exact lift and duration of my cam in a few days. Im almost positive the lift will be more than .450 so i will have to get these heads right??http://www.sdpc2000.com/cart.asp?action=prod_detail&catid=277&pid=782
There the same as stock vortec heads but with better springs? and better valves?

 

http://www.sdpc2000.com/cart.asp?act...id=277&pid=782

 

You don't necessarily need the better heads to get lift of over .450", the OEM springs limit the lift beyond that. You'll need new/better springs and to make sure that the spring retainers don't hit/get close to your valve seals. Vortec heads are good for about .480"-.485" before interference, I believe. The HP Vortec heads from SDPC are worth the money, but just may not be necessary in your case, that's all. Also, performance camshafts obviously need better/stronger springs than the ones they give you even if the lift is .450" or less. The high ramp speeds of XE Comp cams, for instance, require a stiffer spring to prevent valve float at high rpms.

 

FYI my set's retainers hit the seals at .468 and the set of modded heads from SDPC are rebuilt and not new from the last time that I checked. The springs are not hard to change and you can use Crane .050 offset keys and .050 shims to gain more lift clearance without machining.

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91 RS L31 350..... Vortec heads..... Holley 670..... Edel. intake .... Lt4 cam 1.6 rollers ..... Edel. TES headers .. 3" exhaust ..... 5spd 3.08

 

For a little more money you can now get the Edelbrock 170cc E-Tec aluminum vortec heads, $999 at Summit for the pair, and they come set up guide plates and springs that will go up to .575 lift. I've been thinking about getting some.

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92 Camaro RS 5.0 5-Speed (Quasar Blue)
T-Tops
14" Open Air Cleaner
3.08 Posi-trac
Edelbrock TBI Intake
Crane cam
Ported & polished stock heads 3 angle valve job
HyperTech Chip
SLP Headers (Ceramic Coated)
UltraFlo cat-back exhaust

74 Dodge Dart Sport 360 (11.2 1/4 mile)

2000 Dodge 1500 Ram Sport

[This message has been edited by DartByU (edited August 04, 2001).]