Floorman279

iTrader: (11)

so measuring rod length, i have the 1.8 from YT that are 8 pieces, since the int and exhaust rockers are connected on 1 shaft. so i get what i think is my good measurement, and was told from there to add the .030 preload for the 2126s and do rocker bolt turn method to double check im right. so i should be ending up right at 5 o clock, 6 o clock max, 4 o clock min. so i finger tight both bolts, i turn the bolt and end up getting a little over 6 o clock, ok so maybe take off .005 right? so i check the other side and what do you know, i come up at 4 o clock or a little under......i then figured that they will influence each other, so i swapped and did the other one first and now my values are the same but on opposite valves. whichever one i turn first comes up long and whichever i do last comes up short........so i pulled the rod from one side and tried with no rod, and now im getting some really odd number.

so with rockers that are in pairs, how do i do this method properly and accurately to double check my measurements?

Floorman279

iTrader: (11)

found out that for me personally it worked better to have the opposite one i wanted to measure at 0 lash before i ratcheted the other, so one should always be at 0 lash of the pair.

blackdak318

iTrader: (3)

The rocker bolt turn method is not super accurate and should only be used as a very rough double check. I just went thru this same thing (measuring pushrods) and tried using the bolt turn method to determine my actual pushrod length. Luckily I was talked into redoing it by both Johnson and Manton. Do the zero lash plus your .030 method then use the bolt turn just to make sure you're not turning like 1 full revolution when you only need 6/10 turn (.030/.050 = 60% or 6/10th of a turn). I came up with totally different and I'm sure more accurate numbers using the zero lash then add .030 method.

Floorman279

iTrader: (11)

such a debatable thing, but honestly to me it seems pretty darn accurate.

blackdak318

iTrader: (3)

In theory it is, but my experiences in real life tell me it isn't. The zero lash, measure with a caliper then add your preload is MUCH better. If you're using a normal lifter with a big preload window the bolt turn is probably ok, but any ST lifter where they only want a + - .005 there is no way the bolt turn method would get you close enough.

Floorman279

iTrader: (11)

i gave a full length response in the other thread.