My 4.6 Project engine

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akadeutsch
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Re: My 4.6 Project engine

Post by akadeutsch »

guilty. :smack: I see this has been a covered issue. :deadhorse: I am using the comp timing set. it is the perfect compliment for the cam and will need no machining to fit. I had a bad night thinking I might have to re order a cam. Thanks for setting me straight.
And now to the oil pan. I'll spend some time searching before I ask about that. Right now its not even close to fitting.
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SilverXJ
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Re: My 4.6 Project engine

Post by SilverXJ »

I had the same problem with one of my pans against the main gridle. Needed some clearancing with a BFH to get it to seat. Major hang up was at the front. Wear ear plugs. You could also try an earlier oil pan to see if it might fit any different. Do you have a HV oil pump?
akadeutsch
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Re: My 4.6 Project engine

Post by akadeutsch »

Regular volume oil pump.
akadeutsch
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Re: My 4.6 Project engine

Post by akadeutsch »

After beating on it all day it finally fit
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akadeutsch
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Re: My 4.6 Project engine

Post by akadeutsch »

The head in on. Now to check for push rod length.
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akadeutsch
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Re: My 4.6 Project engine

Post by akadeutsch »

Manifolds are on.
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akadeutsch
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Re: My 4.6 Project engine

Post by akadeutsch »

So I checked push rod length, but I dont really know what to shoot for. I think I like the ones I have. They could be a 1/16"th shorter but what would I gain? My stockers seem to fit with only about 1/16th" preload. Here is where I got that number. I took the rockers off their pedestals in pairs like you would expect; two rockers under one bridge. I then placed the push rods in their respective lifter making sure I could feel the travel in the lifter through the push rod. Then I placed the rockers back on the pedestal and started to turn down the rocker bridge cap bolts. When all of the play was gone from the push rod I looked to see how much space was left under the rocker bridge before the bolt was down all of the way. There was about 1/16 of an inch. I take that to mean that the push rod is engaging the lifter that same amount. That sounds perfect to me. How much preload do I want in my lifters?
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Re: My 4.6 Project engine

Post by SilverXJ »

1/16" is a little high. But you really don't have a precise measurement. When measuring like that the point where the rocker contacts the valve tip is the fulcrum. So, the true measurement will not be under the arm. I also see no mention of a measuring instrument.

To properly measure with minimal tools is to start as you just did. Tighten the rocker arm done until the play is removed from the pushrod. now, using the flat on the head where the valve cover sits and a straight edge make a mark on the push rod. The finer and thinner the mark the better. It might be easiest to color the pushrod with a black sharpie then just scored the pushrod with a straight edge. That will be mark #1. Not torque the rocker down the rest of the way. Make another mark, #2. Not remove the push rod and with a caliper measure between the two marks.
akadeutsch
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Re: My 4.6 Project engine

Post by akadeutsch »

That seems like a pretty good way to go about it. Although I dont like the idea of measuring a mark on a rod. I also forgot to mention that I also used an adjustable push rod to check length. After many many adjustments and a lot of double checking. I am certain that I can get zero lash using a push rod ~ 1/16th inch shorter than my stock push rods. I am sure of this because I made my adjustable push rod exactly 1/16" shorter than my stockers and when I tighten it down there is no play...any shorter and I start to feel play in the rocker arm. So I know that I am engaging the lifter ~ 1/16th". At a cost of 200 bucks do I NEED new push rods?
jsawduste
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Re: My 4.6 Project engine

Post by jsawduste »

That is a hack job on the oil pan. You can do better. 93 HO pan with the Melling HV pump fits on with no banging. That looks like shit.

Where is the tip of the rocker wiping on the valve stem ? Look and see.

Logic would suggest that if you whack 20-30 thou off the block and another few off the head then a shorter pushrod is in order. Screw your freeplay. What is the tip of the rocker arm doing on the tip of the valve stem ? Yes there is quite a bit of travel in a lifter but you really need to look at the bigger picture.

Take a step back, your running out of enthusiasm or have suddenly gotten in a hurry to finish this up. As a result your cutting corners. Don`t do that.
akadeutsch
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Re: My 4.6 Project engine

Post by akadeutsch »

I think what you are saying is that I do need shorter push rods. Why is it important where the rocker hits the valve head? I think you are right about me getting excited. I just want it to run already.
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Re: My 4.6 Project engine

Post by akadeutsch »

And as for the oil pan. It took what it took to get it to fit. I personally don't care what my oil pan looks like.
akadeutsch
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Re: My 4.6 Project engine

Post by akadeutsch »

I had to bring my pushrods to work to measure them using an inside mic. The stock length is 9.644". As for the adjustable, here is how I set the length. I adjusted it pretty short and installed and torqued the rockers and bridge over the adjustable. I then lengthened the adjustable pushrod to almost zero lash...as tight as I could get it with the pushrod installed. I then took the pushrod out and gave it a quarter turn to make it that much longer. I called this zero lash. I then reinstalled the pushrod and I did indeed have no play. I then took the pushrod back out and gave it one full turn (~.050) to make it longer. I reinstalled it one last time to triple check that I had no play and I did not. I believe that I should be engaging the lifter ~.050-.060 at this point. The final length of the adjustable pushrod after decking .025 from the block, .006 from the head, and having the valve seats replaced is 9.533";
now I just need to find them. :banana:
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Re: My 4.6 Project engine

Post by SilverXJ »

akadeutsch wrote: I then lengthened the adjustable pushrod to almost zero lash...as tight as I could get it with the pushrod installed. I then took the pushrod out and gave it a quarter turn to make it that much longer. I called this zero lash.
The lifters are pretty soft w/o out oil in them. You found 0-lash when you extended the pushrod when it was installed. A quarter turn past that point and you are applying preload, past the 0-lash point.
jsawduste wrote:Logic would suggest that if you whack 20-30 thou off the block and another few off the head then a shorter pushrod is in order. Screw your freeplay. What is the tip of the rocker arm doing on the tip of the valve stem ? Yes there is quite a bit of travel in a lifter but you really need to look at the bigger picture.
Keep in mind that our stock valve train is non adjustable. The pushrod doesn't set rocker sweep on stock rocker arms, which he is using. You also can't set the sweep with the pushrods with this configuration. Even on my HS adjustables (style where the adjuster is over the pushrod I still can't set sweep with the pushrod. That would have to be accomplished by either milling the rocker pedestal or using shims. In order to do so you would need stud mount rockers that adjust at the stud. Also, using stock arms the sweep pattern is going to be pretty large and hard to judge. I'm not 100% sure how sweep would look using a stock rocker as I haven't tried it. The only way a pushrod would effect sweep in this situation is simply by the small angle changes of having a longer rod. With the small lift amounts we are running (considered small in the wide range of performance engines) I don't even think that little bit of angle change would even be noticed in the sweep pattern.
akadeutsch
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Re: My 4.6 Project engine

Post by akadeutsch »

My rockers appear to be resting on the middle of the valve head. Silver, I guess you are right about finding zero lash, but that quarter turn was actually only ~.005. It was just hard to extend the pushrod as far as I wanted to with it installed. Also, I have double checked the adjustable and one turn gets you ~ .020 change in length. So my original 9.533 is actually only .030 preload. After much measuring and thinking I will order 9.540" pushrods making my lifter preload ~.040. Now to run off and triple check. 9.550 is the closest that I can order. Trend Part # T955805. Preload will be ~.050. Do I need 210° Clearance?
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