Use a minimal adjustment parameter eliminating the flex and loss of valve train-stability problems associated with most adjustable pushrods Tapered 7/16 4130 chrome moly adjustable pushrods, use a minimal adjustment parameter eliminating flex and loss of valve train-stability problems associated with most adjustable pushrods. Designed to exceed the needs of performance engines using larger lift camshafts and high spring pressures Individual length intake & exhaust pushrods keep the adjustment extension to a minimum CNC-machined Can be used with hydraulic or solid lifters and street or race engines