Cam experts within...........

[Blown WS6]

ok i just got my new Comp Cam and before I put my engine back together I want to know if I'm going to need aftermarket valve springs for a cam with these specs.
Lift- Intake: .500 Exhaust: .510
Duration @ .050- Intake: 210 Exhaust: 220
And its got a lobe seperation of 114

Or can I use stock valve springs till I get the new heads?

------------------
91 Firebird Formula
L98 w/ATI P600B ProCharger, 2 core intercooler, 9psi (new L98 coming soon)
Pro-Built Stage 3 700-R4 w/ Continental 2400 stall TC
C5 wheels and tires
http://www.suempresaenlinea.com/drowned/images/transam-front-gray.gif

92 Firebird Convertible- L03, 700R-4
Bone Stock
http://www.suempresaenlinea.com/drowned/images/transam-front-green.gif
"Those people that tell you not to take chances, they are missing what life is about."-Metallica
Crazy street racing idiot member of the All-Powerful Nor-Cal crew


Member- Trans Am Club of America (TACA)
Founder- Nor-Cal F-bodies

ASE Certified- Parts Pro, Engine Repair, Engine Performance L1

[Bad406Z]

Trevor I will talk to my buddy at performance auto swap and see what he says. I will get back to you tommorow or post.

[MATEOZ28]

Post this over at thirdgen bro they are the techsters.

------------------
Part of the notorious
*GEARED FOR LIFE*
Super chevy crew
http://www.IROC-Z.org
ALL POWERFUL NOR-CAL
http://www.virtue.nu/mateoz28/mateo.gif

"Never underestimate the idiocy of stupid people in large groups"
MATEOZ28

Proud hater of *Have your name here* the village idiot.

[MATEOZ28]

Post this over at thirdgen bro they are the techsters.

------------------
Part of the notorious
*GEARED FOR LIFE*
Super chevy crew
http://www.IROC-Z.org
ALL POWERFUL NOR-CAL
http://www.virtue.nu/mateoz28/mateo.gif

"Never underestimate the idiocy of stupid people in large groups"
MATEOZ28

Proud hater of *Have your name here* the village idiot.

[Wardo]

For the cost of a set of springs don't even fuck around. First off the stock srings wont handle it, secondly why even think of risking a broken spring with a brand new motor?

------------------
88 Iroc, L98, SLP headers, Edelbrock cat back, K&N's, ported plenum, FPR, all the free shit, Lakewood LCA....

67 Camaro bracket car, .030 427, Dynamic 400, narrowed Dana 60, 5.13's, ladder bars, 3200lbs and 10.60's all day long.

[Blown WS6]

Because I will only be running these springs for a few months before I get my new heads.

[Conv389drv]

What I've read and what I've seen in spec guides says that if you run that much lift (I think anything over .450 ?) you can't use stock springs. Go ahead and upgrade to springs that are rated for that much lift.

[Wardo]

Even only for a few months it not worth it, thats how long it has taken to save the cash for this short block. Plus be real with yourself. You know thast your not going to pussy foot around when the new motor is in. Even if you did take it easy you have to figure the wear on the stock springs along with having to support more lift AND duration.

[Bad406Z]

Why don't you ditch your cam and valve spring and step it up to computer controlled valves and then you can program cam specs into a computer and customize how your car runs!- Ok back to reality is was only kidding

[Ponchojoe]

The stock L98 springs can only take around 470-490 lift if I remember correctly.

For the cost of a set of springs vs the cost of redoing your engine, I would get the proper/correct springs.

Ponchojoe

[nichoulas]

yeah, joes right... ive heard that .488 would be the max lift youd wanna go... however i have heard of people going a little higher, but not as high as .510, with no problems... so i dunno its your vehicle... but you can get some high performance z28 springs for like $50... theyre good up to .510 i believe, look in a chevy magazine... theres a lot of shops that sell these springs that advertise...

[This message has been edited by nichoulas (edited 01-29-2001).]

[Newsance]

Springs are cheap. If you REALLY feel the need to convince yourself, go and install everything, and watch the springs bind.

[IROCKZ4me]

You will need a much stronger spring than stock. On top of that your stock springs are surely tired and not up to the task that they where designed for originaly when new.
Max lift is only part of the story. Cams that have short duration numbers with big lift numbers accellerate the lifter, pushrod, and valve assembly at a much faster rate than cams with both big duration and lift numbers. The valves with a cam like yours open and close extremely fast and it takes a very good spring to control them.
Another problem you can have in your application is manifold boost.
Forced air apps are harder on intake valve springs than natural asperated engines.
Naturaly fed engines have no more than atmospheric pressure(14.5PSI) pushing on the intake valve at wide open throttle. On a boosted app you have atmospheric pressure plus boost pressure trying to shove/hold open the valve. An engine running 9 PSI boost has over 60% more pressure pushing on the valve head.
You will need excellent springs.

------------------
Tracy irockz4me@yahoo.com

'86 IROC-Z Camaro (http://www.geocities.com/irockz4me)

355 CID SBC
Paxton supercharger
NX nitrous oxide
AFR heads
AS&M rollercam
TRW forged slugs
Edelbrock headers
SLP catback
Art Carr Th700r4
lots of other mods
lots of tunes

My other page (http://community.webtv.net/IROCKZ4me/IROCKZ)
Club IROC-Z (http://clubs.yahoo.com/clubs/iroczz28)
Domestic fuel injected performance car club (http://clubs.yahoo.com/clubs/efihightechperformance)

[BEER]

Use the stock ones and see how long it takes the cam and lifters to eat each other.

------------------
Clean 85 Z28 w/TPI, rare black contour interior( 1 of 2,510), almost every option except for a posi rear, go figure.
79 malibu demolition derby car (still have movies to post)
87 parts car, which previously was a high 13 second Lg4 car (broken frame and all twisted up)

[Blown WS6]

ok I am going to get a set of double valve springs from comp cams for $100 here are the specs on them.
part #- 987-16
1.430 2 spring
I.D.- .700
seat load- 138 @ 1.750
open load- 325 @ 1.25
coil bind- 1.150

This is the springs that are recommeded for this cam so I think I'll have to go with these. http://www.3rdgen.org/ubb/biggrin.gif