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Tr 3 head and pushrods

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Hydroglen

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In measuring the head on my Tr 3 it would seem that it has been milled .175.
I think .165 is max. Obviously this head is still working and may need another skimming. Since I plan to relieve the head a little more ( this is a 511695) I should be offsetting the increased compression from skimming. Make sense?
I also have several bent pushrods (ordered new ones). Some mushroomed at the bottom. Is this a weak area for these motors? The valves did not hit any pistons... so why?

Thanks,
Dorien
 
With that much already removed, I wouldn't plan on taking off any more unless absolutely necessary. IMO if it won't clean up with just a few .001" off, look for another head.

The bent pushrods sound like valve spring coil bind to me. Be sure to order new ones that are shortened to match the head.
 
If I recall correctly weren't earlier pushrods narrower and weaker? That possibly is an alternative reason you have some bent ones.
 
It wouldn't hurt to re-check your head. Measure from the gasket surface to the top of a machined surface (like where the 511695 is engraved). Initially when new it measured 3.330"

Just to be sure it's .175 milled off (which is huge)
 
Thanks guys....I am getting a spare motor with the same head in a week or so.
Hopefully it is more stock.
Will also look at the springs for coil binding, but did not notice anything when I compressed them to remove the valves.
Dorien
 
Peterk wrote []]It wouldn't hurt to re-check your head[/

Thanks...I had done that, but went and did it again with my old style calipers and the result was OK .75
Guess at my age I should not be fiddling with a digital unit and it's fancy screen LOL

Thanks for the suggestion....
Dorien
 
Hydroglen said:
Will also look at the springs for coil binding,
Click to expand...

Likely you know this, but JIC: if there was a problem with coil bind, it would be because it has a high lift cam and/or high ratio rockers.
 
If it is all as you imply, then I can assume that the extra "work" has worn out the pushrod?

Ok Just to be sure can you give me the "normal" lift?
I think 0.240 is gross lift.
So with a bit of improvising I should be able to set up my magnetic based dial indicators on the block, insert tappets and maybe a sawed off pushrod ( the broken ones)and spend some time.
Thanks,

Dorien
 
TR4nut said:
If I recall correctly weren't earlier pushrods narrower and weaker?
Click to expand...
They were. But I put somewhere in the range of 150,000 miles on them, and they were still fine. I only swapped them out because I needed shorter ones.
 
Read your post...did not realize there were different lenghts.
Moss never asked me for what lenght I needed.
Guess I will find out when I get them.

Dorien
 
Hydroglen said:
Read your post...did not realize there were different lenghts.
Moss never asked me for what lenght I needed.
Click to expand...

Moss only carries the standard length. For shorter ones, you'll have to go to someone that specializes in racing parts, like Racetorations or TSi. I got mine at BFE
 
TR3driver said:
... I got mine at BFE
Click to expand...

That's where I got mine from. Get the head skimmed flat before you call so you know what the final figure is. I cut 0.090" off to increase the compression ratio. You'll probably be close to that figure.
 
I should have added, you only need shorter pushrods if the head has been skimmed to increase compression. Normal "service" skimming shouldn't remove enough to worry about.

Larry Young gives the gross lift as .238", but remember that is at the camshaft. Stock rocker ratio is a bit under 1.5:1, so the springs should allow for .360" movement. (This leaves a bit extra, once you account for valve lash, flex in the valve train and so on. But a little safety margin is a Good Thing, IMO.)

But as you can see, "performance" cams may have as much as .390" gross lift and there are high ratio rockers available as high as 1.7:1. The combination of the two would give you gross lift over .660" ! (Which would be silly on the street IMO, but then so is removing .175".)
 
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