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Discussion Starter #1 (Edited)
Ok, my head gaskets are being delivered today, so tommorrow I'm finally bolting the heads on for good... so then I need to do my push rod check...

I've been reading and watching videos.... and seems there are some differances on the way this is done ect.... so....

1. Do I use my new (unpumped up of course) lifters, and then do the zero lash (just about when I can't spin push rod anymore or I read thats not right and you turn it until you can't rock the rocker anymore?), and then set the pre-load (set torque wrench to 20 ft lb) and then turn wrench 1/4 to 3/4 turn and I should hit the torque, if past 3/4 turn there too short, if under 1/4 too long? this right?

Or do I use the old lifters that I welded the top edge and made into solid lifters, and just set it to zero lash (nothing else) then move on to step 2?

Personally I think you would want to use the solid lifter if i'm understanding this all right... but my ?, is the normal lifters when running pumped up all the way to the top normally? becuase if not, then this will be off/different correct?

2. Once I get step 1. done, I then color in the tip of the valve with a black dry erase marker..., turn the engine over a couple times, and then take apart... I should then see the mark where it rubs the marker off in the middle, and the thickness of this line should be about .080"??? (.070"-.095" is accetable??? what I found listed on LMR site) do this on both intake and exhaust and on the 4 corners right?


Now, I'm using GT40P heads, with Scorpiion 1.6 Rollers (pedistal) , I cleaned up 2 of the old stock push rods that I will be using for my test... I also have the ford racing shim kit I bought just in case... so now, if the mark isn't were it needs to be and the thickness is greater or less then the .080" range( or .070-.095 range if that's whats allowable)... I will then need to order a adjustable push rod, and start over doing the same steps correct? (I can use the adjustable push rod with the springs on right, I don't need to use weaker (test) springs, I've seen it both ways so it's confusing

if the mark is off the center towerds the intake I can try just adding a shim right?

Now I also read, that shooting for the center is wrong... its the swipe (thikness) of the wear mark that you need to worry about first (you want the thinnest swipe), then you just need to make sure it's not riding to close to the edge, don't have to be dead center...

So...... what's right?????? LOL
 

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Discussion Starter #2
ok, I took my first stab at checking the push rod wear pattern... the dry erase marker I had is dried up, so I had to use a permenat black marker... which didn't appear to wear too much off, even though I turn the motor over to work each rocker more than twice... so I grabbed a dry erase marker from work today and will try again when I get home... but this is what I got so far... the exsuast one got messed up, guess I moved the rocker while adjusting, so it got all messed up... I used the solid lifters I made and just adjusted for zero lash.. thats it and turned it over... if I'm doing it right, I belive I got .08x" and it's pretty much center on the intake....

Then I took those solid lifters out and put in the new stock ones... and adjusted for zero lash and then torqued to 20ftlb... I got a 1/4 turn, I belive if under 1/4 turn I would need longer push rods... so I guess I'm on the edge of that... but I still need to make sure my wear pattern is right... so I'll try again today.... I'm kinda supprised though... I would of thought my push rods would of ended up being a little longer... since the reman gt40p heads look like they were shaved a little... my block deck is stock... and I'm using a gasket this is suppoe to be .042" compress... I'm using my stock push rods just for testing... I am still going to buy new ones... just need to know if stock size are fine or if I need a little longer ones..
 

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Discussion Starter #3
I didn't get to mess with it last night, I went ahead and orderd the trickflow push rod lenght checker so I'm waiting for that to come first...

but anyway.... I seen the stock push rod's listed as 6.250 and 6.272... so which is it? I mesuared one of my stock ones this morning and it is coming up as 6.253 (so looks like it's 6.250)????

The ford racing ones list theres as the 6.272... This is really driving me crazy... when I did my first test, I was able to get just a hair past 1/4 turn on the intake, but I belive the exhust I was right at 1/4 or just a hair before... so its close... I think it would be better if I could get closer to 1/2 turn just to be safe... so if I really do have 6.250 and Fordracing ones are 6.272 that might do it??? the next ones I can find are 6.300 from trickflow but now that would be double the money @ 99.xx.
 

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U want zero lash, meaning no preload on lifter plunger, and then 3/4 turn to torqued. 6.250 is stock length. Don't overthink this.
 

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Discussion Starter #5
U want zero lash, meaning no preload on lifter plunger, and then 3/4 turn to torqued. 6.250 is stock length. Don't overthink this.

Well here's what happened... after more testing/checking... I found out... the old stock lifter I made solid vs the new ford racing lifter... there was a .020 difference for zero lash.... for example, cyl #1 intake - if I put the adjustable push rod in and make it small, then put the rocker on and tighten down the bolt, then adjust the rod out until I have zero lash, then remove the rocker and measure... with the solid lifter I got 6.206 if I did the same with the new lifter I got 6.227.. the top part the push rod sets on does look a little difference... so looks like ford changed it a little....

also, I found I also have .020 difference between the drivers side head and pass side head... so the drivers side needs .020 more push rod then the pass side... I bought these remanufactured gt40p heads from LMR, the surface is smooth so it's been machined... but what was took off who knows... but before I put them on.. I did take the digital calibers and measure each head from the surface face to the top of the lower head bolt area where it's flat on the corner... (wasn't sure how else to do it that like the only to flat areas I can reach with the calibers) and I got 1.37xx on one and 1.38xx on the other.. so they were close... so maybe the valves are ground more on the one then the other? the pedestal perch area might be diff who knows.. heads from different production runs?

so what I figured.. I set the adjustable rod to 6.300, then added a .020 shim to the drivers side, and a .040 shim to the pass side (so this should make them the same, push rod length wise)... so know I get 1/2 turn pre-load hitting 20ftlb torque on both heads. If I used next size 6.350, then it would go a full turn (maybe just slightly past).. and I don't want to add any more shims... (I did this on all 4 corners)

So I ordered the trick flow 6.300 push rods (will be here tomorrow) and will use the .020 shim on the drivers side and the .040 shim on the pass side.
 
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