If your heads are not milled for guide plates, then the pushrods are guided by the heads themselves. The hole where the pushrod comes through the head acts as the guide. If you use self aligning rockers with that head, you could cause the parts to bind up, because they are trying to be guided by two different spots. Use regular rockers.
Self aligning rockers are intended to be used with hydraulic cams and on GM factory heads made from 87-99, and some aftermarket heads designed to use factory parts. These heads do not have integral pushrod guides, the pushrod holes are enlarged. Earlier heads have smaller pushrod holes, usually with straight sides, that are designed to be an integrated pushrod guide in the head.
Self aligning rockers are not a good choice for performance applications. By design, if the engine ever experienced valve float, the rocker could jump off the end of the valve, sending the valvetrain parts out of alignment, and cause extra mechanical damage. Guideplates, and heads with integral pushrod guides, do not have this problem.
Bottom line is, your heads have integral pushrod guides. You don't need guide plates or self aligning rockers. Just use regular style rockers. If you use a cam with higher lift, check pushrod clearance where it comes through the head. Sometimes those holes need to be elongated (kept the same width, but milled a longer length) when using higher lift cams.
If you plan on running a high lift cam, at high rpm, with higher spring pressures, then you might want to then have the heads milled for guide plates and screw in studs, and have the pushrod holes enlarged. This is the best solution for performance use, short of a shaft rocker system.
Hope this makes sense.
Self aligning rockers are intended to be used with hydraulic cams and on GM factory heads made from 87-99, and some aftermarket heads designed to use factory parts. These heads do not have integral pushrod guides, the pushrod holes are enlarged. Earlier heads have smaller pushrod holes, usually with straight sides, that are designed to be an integrated pushrod guide in the head.
Self aligning rockers are not a good choice for performance applications. By design, if the engine ever experienced valve float, the rocker could jump off the end of the valve, sending the valvetrain parts out of alignment, and cause extra mechanical damage. Guideplates, and heads with integral pushrod guides, do not have this problem.
Bottom line is, your heads have integral pushrod guides. You don't need guide plates or self aligning rockers. Just use regular style rockers. If you use a cam with higher lift, check pushrod clearance where it comes through the head. Sometimes those holes need to be elongated (kept the same width, but milled a longer length) when using higher lift cams.
If you plan on running a high lift cam, at high rpm, with higher spring pressures, then you might want to then have the heads milled for guide plates and screw in studs, and have the pushrod holes enlarged. This is the best solution for performance use, short of a shaft rocker system.
Hope this makes sense.
