NSA or SA rockers??
12-17-2006, 08:33 PM
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NSA or SA rockers?? I've got most bolt ons and am planning on doing a 1.6RR upgrade. My question is if I should go non-self aligning or self aligning? I've heard that with high lift cams you should go NSA. I do not plan on doing a cam for a long time and if I do, it probably won't be a very aggressive cam. Also, what is the significance of the different stud sizes and which is better? Thanks.
12-17-2006, 08:46 PM
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NSA rockers are cheaper, but require guideplates and hardened pushrods. I don't know if there are any actual functional advantages. As far as the studs, 3/8 will be fine if you stay near stock. If there is any chance that you will ever go to a big cam and heavy valve springs you should upgrade to 7/16 now. If not, you will have to replace the rockers later.
12-17-2006, 09:05 PM
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you are ok with the self aligning rockers for now unless you plan on going into the 6500 range on a high horsepower setup. even with a not so agressive cam, if you are putting out 400+ hp you want to go with non self aligning rockers for proper valvetrain geometry, the self aligning rockers will pop off the stud and break springs, studs, etc.
12-17-2006, 09:19 PM
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Originally Posted by 95FbFormula
To use guide plates at least the gm ones you have to upgrade to 7/16 studs.
12-17-2006, 10:06 PM
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SA also require -.050 locks on most aftermarket valves... for tip clearance. Most aftermarket valves (Manley for sure) have .250 tip, and with the SA rockers you'll need to use a -.050 lock to gain needed rocker to retainer clearance at the tip. This may affect geometry and choice of springs/amount of machining needed.
FWIW, with Crane Gold Pro Magnum 1.6 RRs SA, -.050 locks, Patriot Gold dual springs (yup, you can get them for LT1), Manley RaceFlo valves, and XFI 282 cam, I have about 170 seat and 310 open pressures (7/16 would be a good idea) and about .110 before coil bind. This is with seats NOT cut for clearance; another option was to cut seats and use a less serious spring. With the Manley RaceFlo valves, or any other valve with .250 tip, you still need the -.050 locks, but byy cutting seats you can reduce spring pressures.
FWIW, with Crane Gold Pro Magnum 1.6 RRs SA, -.050 locks, Patriot Gold dual springs (yup, you can get them for LT1), Manley RaceFlo valves, and XFI 282 cam, I have about 170 seat and 310 open pressures (7/16 would be a good idea) and about .110 before coil bind. This is with seats NOT cut for clearance; another option was to cut seats and use a less serious spring. With the Manley RaceFlo valves, or any other valve with .250 tip, you still need the -.050 locks, but byy cutting seats you can reduce spring pressures.
