new engine build. yella terras?
new engine build. yella terras? hello, I have some concerns in my choice of rockers (that i already own) for this engine build. i have a set of the old style yella terras that are known to be a bit heavy on the valve side. this car will see some slightly unusual situations, being that it is a daily driver in colder conditions ( think 0 degrees during the harder months) and it will also see some auto-x track time. will the higher /sustained rpms around 4-6 grand and the temperature fluctations cause enough of a detrimental effect to make these a poor choice? ive heard conflicting reports about these rockers, mainly with the high rpm ranges. the rockers are well built in my opinion, however again i am concerned of the usage of this motor killing the reliability of the valvetrain under the higher than normal rpm loads that it will under no doubt see. ive included the engine build-to-be for any additional information that you could use. anyone who is familliar with these kind of stresses on the motor, point out the weak links if any in this system.
specs are
stock ls1 short block. plan on around 11:1 compression.
ported ls1 heads, mild to medium port job. 2.02/ 1.6 valves, possible titanium on the intake side.
tr224 224/224 cam with .567 lift @ 1.7 rocker ratio, 112 lsa (1500rpm-6600)
chrome moly hardened pushrods
comp cams 918 beehive valvesprings good to .600 lift
titanium 10 degree retainers and steel locks
ls6 intake, polished TB
headers, some kind of new timing chain and ls6 oil pump to come....
nine-eight
specs are
stock ls1 short block. plan on around 11:1 compression.
ported ls1 heads, mild to medium port job. 2.02/ 1.6 valves, possible titanium on the intake side.
tr224 224/224 cam with .567 lift @ 1.7 rocker ratio, 112 lsa (1500rpm-6600)
chrome moly hardened pushrods
comp cams 918 beehive valvesprings good to .600 lift
titanium 10 degree retainers and steel locks
ls6 intake, polished TB
headers, some kind of new timing chain and ls6 oil pump to come....
nine-eight
Last edited by nine-eight; Mar 10, 2007 at 03:14 PM.
Your build sounds fine. The only problem with the Yella Terra's is the weight. With the combo your running, you are not putting alot of strain on the rockers, so my suggestion would be to stick with the stockers. The YT's could cause unwanted valve float, and usaully needs a healthy spring. They would probablly test the limits of your 918's. Stock rockers have been proven in much more radical combo's, so sell the YT's and make you some money back. 
beast- great, ive had those thoughts in the back of my head. even with the auto-x, the stockers are sufficient? and what is your opinion on the bearing issues with the stockers? i remember something about a nasty-nate on this forum awhile back that was known for doing some work to the stockers to help hold the bearings more securely in the rocker... any opinions on that?
