Valve spring decision. STEP IN!
Thread Starter
Instructor
Joined: Oct 2005
Posts: 198
Likes: 0
From: Seattle Wa
Valve spring decision. STEP IN!
Background: Ported LS1 heads comp 921 dual springs and a shaft about .600 lift 230ish duration ( vette Dr H/C so they wont give definate specs) stock rockers.
Ok well i am about to order the crane roller rocker kit so that i will have adjustable rockers, and poisibly get rid of some valvetrain noise associated with the cam/stock nonadj. rockers. my question for you is VALVE SPRINGS. Im trying to decide to replace them while im at it or leave them alone.
Does anyone have any complaints about the comp 921's?
Does anyone have any praise from the patriot performance golds?
I will run a dual spring but if anyone has any other input my ears are open.
Ok well i am about to order the crane roller rocker kit so that i will have adjustable rockers, and poisibly get rid of some valvetrain noise associated with the cam/stock nonadj. rockers. my question for you is VALVE SPRINGS. Im trying to decide to replace them while im at it or leave them alone.
Does anyone have any complaints about the comp 921's?
Does anyone have any praise from the patriot performance golds?
I will run a dual spring but if anyone has any other input my ears are open.
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Well, I am running the Cranes and have run into an issue. After reading this post, not sure how to answer you!!!!!!!!
Read page 6 of this post
Read page 6 of this post
Drifting
Joined: May 2003
Posts: 1,715
Likes: 1
From: cAshburn VA
Never heard of a complaint with the 921s. I would stick with them!
I would not up the rocker ratio without knowing what my lift is.
I would at least pose your new setup to them and ask if there are any issues, if they wont tell you the lift outright.
Man, I still don't understand why someone would put a cam in their car without knowing the specs. UFB, un-F-believable!
Good Luck!
I would not up the rocker ratio without knowing what my lift is.
I would at least pose your new setup to them and ask if there are any issues, if they wont tell you the lift outright.
Man, I still don't understand why someone would put a cam in their car without knowing the specs. UFB, un-F-believable!
Good Luck!
Team Owner
Joined: Apr 2001
Posts: 26,795
Likes: 614
From: Elmhurst, IL (West Suburb of Chicago) & Home of MEGA Horsepower
St. Jude Donor '06
The 921 dual springs are just about the best dual springs that $ can buy for cammed up applications like yours (and the most pricey that fit stock heads w/out machining) 
. If it ain't broken don't fix it,unless they have 35,000 excess miles on them and if yes, replace them with new 921s as i have never heard of a single failure with these springs.
. If it ain't broken don't fix it,unless they have 35,000 excess miles on them and if yes, replace them with new 921s as i have never heard of a single failure with these springs.
Thread Starter
Instructor
Joined: Oct 2005
Posts: 198
Likes: 0
From: Seattle Wa
hmm
Originally Posted by vettenuts
Well, I am running the Cranes and have run into an issue. After reading this post, not sure how to answer you!!!!!!!!
Read page 6 of this post
Read page 6 of this post
Safety Car
Joined: Dec 2003
Posts: 4,040
Likes: 3
From: "Same as it always was"
Originally Posted by BLOWN ECS Z06
The 921 dual springs are just about the best dual springs that $ can buy for cammed up applications like yours (and the most pricey that fit stock heads w/out machining) . If it ain't broken don't fix it,unless they have 35,000 excess miles on them and if yes, replace them with new 921s as i have never heard of a single failure with these springs.
. If it ain't broken don't fix it,unless they have 35,000 excess miles on them and if yes, replace them with new 921s as i have never heard of a single failure with these springs. Mines in the shop now with a broken spring #5 cycl...I always let it warm up to at least 140 before even driving it! The 921 spring broke in two places on the ends. I also read on another forum that someone had one break on them too.
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Melting Slicks
Joined: Sep 2003
Posts: 2,911
Likes: 1
From: Augusta GA
St. Jude Donor '05-'06
Originally Posted by stano
Mines in the shop now with a broken spring #5 cycl...I always let it warm up to at least 140 before even driving it! The 921 spring broke in two places on the ends. I also read on another forum that someone had one break on them too.
Wow! That sucks! How many miles on them? I am on my 2nd set of 921s and love them. Bump!Dave
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Which Crane rockers, hope not 1.8's with 921's
Also, with ported 241's, careful of spring load as there have been a few cases of breaking through the weakened casting from porting.
Also, with ported 241's, careful of spring load as there have been a few cases of breaking through the weakened casting from porting.
Le Mans Master
Joined: Jun 2004
Posts: 7,156
Likes: 154
From: The Arid Sunny Desert
So far so good with the Springs. As for the exact setup, I know what you mean. Vette Doctors are a great shop but I'll be damn if I know exactly what the specs are on their proprietary packages. Ancient Chinese Secret?
Thread Starter
Instructor
Joined: Oct 2005
Posts: 198
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From: Seattle Wa
Originally Posted by ALLTHROTTLE&NOBOTTLE
You know I like the PP golds
Instructor
Joined: May 2011
Posts: 194
Likes: 47
Many of us are in the VIN range of potential valve spring issues. And, according to many, this should be an “early engine life failure” if it’s likely to occur. Do we know what the highest mileage reported with a broken spring?
Drifting
Joined: Mar 2015
Posts: 1,421
Likes: 302
From: CSRA, SC
This is a 15 year old thread and there are many many more recent posts on this topic. I replaced my springs around 55k miles as a proactive measure as the posts I read indicated that it's a random issue largely unrelated to miles.
