Engine threaded bosses

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Doppleganger

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Just wunnerin if anyone knew what these hole were for. I replaced my 85 5.7 with a 97 5.7.....just wondering if there should be plugs in unused holes or is there missing bosses with the newer block.

Left rear side
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Right rear. Is the smaller hole for a dipstick tube? Looks awfully small (thats what she said).
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Lugnut

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No o-ring that I have ever seen, I usually just put a little RTV around the dipstick tube where it bottoms out in the block and never had any problems.
 

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The small threaded hole is left over from the older ram horn style exhaust manifold set-up, it’s where the spark plug heat shields bolted on.
 

Doppleganger

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Whats funny is....I dont think I have a tube for it. I bought this motor as a short block and dont remember seeing a dipstick in it.

I see they have 'performance' dipstick tubes. Didn't realize such a thing could make the truck go faster.
 

Lugnut

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Make sure you get a pass side dipstick tube. The left hand ones are different length and dia.


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FYI, Here is a pic of the heat shields I was talking about.
 

Doppleganger

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Couple more on the left rear side of the block. I only ask about these because the guy that built the motor stripped it to hot tank it, so not sure if there is anything missing, like a plug, etc. Also, many times bosses this close to an oil filter will work for an oil pressure sensor, etc.

These holes are deep - I can put a longer screwdriver all the way in the back one.

THX

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AKguy

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Seems I have seen clutch pivot studs mounted in those holes, either fore or aft.
 

AuroraGirl

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Whats funny is....I dont think I have a tube for it. I bought this motor as a short block and dont remember seeing a dipstick in it.

I see they have 'performance' dipstick tubes. Didn't realize such a thing could make the truck go faster.
Apparently you havent ever painted a caliper red
 

AuroraGirl

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i think i circled the wrong thing. i think its the large bar above. thats the z bar connection to the threaded rod whoops
pivot

Satisfied....?
I didnt realize today was be a grouch day. If you wanna get about "the original question" then it applies straight back, performance enhancing dipsticks arent about that either. It was a light hearted comment about faux performance things. Like red calipers
 
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