Went

I have a 1989 with the L98. I've bought some self aligning 1.6 roller rockers...Scorpions. With the stock cam will I need to measure push rod length? It would be nice to use the stock push rods if possible till I'm ready to install my other new parts. I've a new LPE cam, intake & runners, valve springs etc., and headers to put in. I am going to put on new valve cover seals and thought why not the roller rockers while I'm there.

Thanks, Went

84Z51J

Always measure! The roller tips must be properly aligned with the center of the pushrod tip or your new parts will quickly become twice as expensive.

https://www.airflowresearch.com/car-craft-nov-2014-pushrods.php

cardo0

OK, I'll make u a list.

1-push rod slots in head. Need to be large enough for closer p-rod angle to head w/1.6 rockers.

2-guide plates need to allow p-rod to operate smoothly but not to tight or to floppy loose.

3-U need enough vlv spring retainer to vlv seal distance plus 0.060" for safety margin for your cams max lift.

4-U need to verify clearance of rocker arm to vlv spring retainer and the slot in rocker for the stud through entire range of cam lift. Thats for both intk and exh.

5- U have know how to adj vlvs/lifters not just assume u can because others can. Terms like "zero lash" and "base circle" cannot be assumed or the cam will eat itself.

Hope this helped.

BOOT77

I just used some stock length pushrods with 1.6 stamped rockers on a stock cam, but when changing to a completely diff style rocker like alum they can move things around from one brand to the next. It's safe to check and learn how so when you do upgrade more later you can check it again. Anytime you change heads, valves, use lash caps, cam, lifters, rocker brand/ratio/style, gasket thickness or have machine work done that reduces a surface you should check.

Go to the hardware store and get a couple lightweight springs, comp sells some test springs but they are too small diameter to fit over most valve seals. With the test spring you can hold up the valve but not compress the lifter. There are three ways to measure a pushrod and I like to use the comp hi-tech tool(not magnum that is another method), it seems to be the more popular spec. Either way you have to check with the new pushrods(with test springs) to make sure they used the same method as you did.

I'm sure you can find the info on the rest GL!

edit: There is some room for error so it don't have to be perfect and sometimes the ideal size is not available unless you wanna custom order so you just gotta get the closest. If you wanna get picky you can have diff length for the intake & exhaust.