Engine Engine rebuild suggestions

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I don't understand why sbc and rocker arm type matters. In fact, if I recall, in the video, he says it works for all types of pushrod engines with hydraulic lifters. That's why I liked the way he explained it. If I understand correctly, there's like two hundred thousands room for error in the hydraulic lifters, so I think I should be ok regardless :)
 

I don't understand why sbc and rocker arm type matters. In fact, if I recall, in the video, he says it works for all types of pushrod engines with hydraulic lifters. That's why I liked the way he explained it. If I understand correctly, there's like two hundred thousands room for error in the hydraulic lifters, so I think I should be ok regardless :)
Well darn, sounds like you and Youtube have it all figured out....
 
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Here's where I'm currently at. The comp cam 6.300 pushrod arrived. It actually measures 6.320". The original pushrods that were in the engine measure 6.240" and the long one I bought from local autozone is 6.395"

Currently, I"m fighting 2 things at the same time-- finding the right pushrod length and getting the lifter preload correct. If I understand it right, both are related-- if the pushrod is the right length, the preload will be at the correct torque within a 1/4-1 revolution of the torque wrench between like 18-22 ft lbs.

The lifters have no oil in them. Just the spring as they came from the factory. Rockers are OEM stamped rockers.

With cylinder number 1, both intake and exhaust valves closed and the lifters at their bottom, I tried different pushrods again. One thing that is still subjective is 0 lash. Some say move the rod up/down and tighten rocker until it stops moving, that's zero lash. Some say tighten until the pushrod stops spinning.

What I discovered is, since I have my lower intake off, I can see the lifters. In fact, since they don't have the oil, I can easily press on them and see the spring within them move up and down. So, to get to 0 lash, I just tighten the rocker until I can see the lifter cup that holds the pushrod go down. Once it goes, I bring it back to the top-- which is zero lash, correct?

Given the above way of finding zero lash, with OEM pushrod at torque, I can still move the rod up/down-- so that one is out.

With the long one from autozone, the 6.395", it takes me like 2 revolutions of the torque wrench to get to 19 ft lbs, so that one is out.

With the Comp Cam one, I seem to be reaching 19 ft lbs consistently at about 3/4 turn. I've tried it on 3 cylinders, on both intake and exhaust on each one. 3/4 turns is within spec, so I should be good ordering those pushrods, correct?

Here's how the lifter looks at 0 lash:
1713844539551.png


Here's how it looks after 3/4 turn preload of 19 ft lbs:
1713844606658.png


Sorry, it's late and those are the best photos my phone would take.

Thoughts on getting to zero lash with my method? Seems more repeatable then feeling the pushrod.
 
I don't do that dry. Euuuuw...... That's a catchy CT ..... hope the janitor ain't watch'n :leaving:
I just did my rockers on the Junk Pyle, while they are 'top secret ' racecar crap they go on just like stock pedestal mount rockers, and the engine is pre-run but that lifter and the area around it look dry on yours. I soak new lifters in oil over night (if I can) before I install them. I used the 'timing order/intake exhaust closed method, torqued at 15ft lbs, per rocker arm manufacturer, and they all got it between 3\4 1 full turn after 0 lash. Now the jury is still out 'cause the engine will not be started anytime soon but everything checks so far.
If you're having an issue with push rod length you should use a solid lifter, a hydraulic lifter can be converted, an adjustable pushrod, there prolly is a tool for that, there is a procedure that uses a lite spring on the valve, my point is not to spend money on guessing push rod length, I'm also suspect on assembling dry.
 
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For others like me, who are reading this thread. I called Trick Flow Specialties, talked to a person for 20 minutes. Very helpful folks, btw. Wasn't the first time I asked them technical questions. I described what heads I have and what's not working. The person told me that pushrods are sold in 0.050 increments. Stock one is 6.250, next one up is 6.300. Doesn't matter what you measure in between, you need to pick one of the two. If you want, they can produce a custom pushrod to your exact size for an extra fee :) He also said that hydraulic lifters are very forgiving. They have a check valve and fill with oil, so they compensate any mistakes people make on the preload/pushrod size. He explained that lifter preload, is the distance the spring-loaded plunger in the lifter travels down. He confirmed what I was talking about in my post with photos. He said getting to 0 lash with moving the pushrod is different for everyone. Some move it with more force some with less, thus the lifter compensates the preload they set. He did confirm the lifters should not be filled with oil when setting preload.

I just ordered a set of their 6.300" TFS pushrods and I should be on my way.
 
Guess a lot of us have been doing it the wrong way for years. I’ll stick with my oil filled lifters as I know how to do it that way. May be different with stud mount rockers.
I am not sure why everyone is ganging up on me there was no attempt from me to say your method is wrong. I am simply gathering information from different people/sources and making my own opinion. What i find i post here for feedback. There are different ways of doing this and I'm looking for the way that makes sense to me. Did not mean to offend.
 
Naw, you have to work harder than that to offend most all of us 'regulars' here. It's just the first time I've heard about dry lifter rocker adjustments, the tech guy is correct about hydraulic lifters being forgiving.
Prolly why I have not had any issues with rocker arm adjustments, they feel sorry for me :doh:
 
The Ford service manuals have you soak the lifters in oil (course they are not checking for pushrod length)
You are supposed to disassemble the lifter and take the spring out or better yet use a solid lifter
The lifter plungers travel ,200 IIRR
You will find reduced travel lifters with plungers that move only .109", considered anti-pump up lifters, made to eliminate valve float
 
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My post was not directed at you just a general statement of what most of us do works so they way the guy from TFS described it is just uncommon. My biggest issue with his statement is how do you get the lifters dry if you are swapping rockers on an already ran motor? I am not pulling the intake, removing the lifters (some require the cylinder heads to be removed to get them out), drying them out, reinstalling them, and then adjusting the preload on my new rockers.

Lots of ways to approach doing things and hopefully this works for you as it's always nice to have more tools in the tool bag than you need vs. not having enough.
 
My post was not directed at you just a general statement of what most of us do works so they way the guy from TFS described it is just uncommon. My biggest issue with his statement is how do you get the lifters dry if you are swapping rockers on an already ran motor? I am not pulling the intake, removing the lifters (some require the cylinder heads to be removed to get them out), drying them out, reinstalling them, and then adjusting the preload on my new rockers.

Lots of ways to approach doing things and hopefully this works for you as it's always nice to have more tools in the tool bag than you need vs. not having enough.
Yea, I got new lifters when I bought the new cam, so for me, it's easy to have them dry. Also, since my engine is on an engine stand and I'm slowly assembling it, the intake is already off so again, that approach works best for me and clearest to understand.

Now, while I'm waiting for the pushrods to come, I need to tackle drilling the ACT hole in the GT40 intake and cleaning. Will post more as I go. Thanks! Julian
 
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