How a great deal on a throttle body spacer can destroy an engine.

[RichLo]

And that scar looks deeper than .060" Did the machine shop already bore it?

 

[Erik the Awful]

"And that scar looks deeper than .060" Did the machine shop already bore it?"

Agreed. https://www.summitracing.com/parts/sum-150100-30

That said, the rust in my TBI block didn't clear up with a .030" overbore, and the machinist and I decided it wasn't significant enough to worry about. Then again, if you're already at a .060" overbore and it doesn't clean up, you've introduced the most likely place the block is going to crack, and .060" overbores are sketchy at best.

 

[PlayingWithTBI]

Also, when they bore the cylinder walls 0.060" they're only taking out 0.030" from each side.

 

[dlindsey19]

So the bolt head snapped off and hopped down the #6 runner? What a dick move.

The bolt that snapped was one of the tbi mounting bolts right next to the throttle bores.

 

[dlindsey19]

I guess I dont understand how the bolt head got down through the air filter and into the throttle body .....are the bolts inside it?

The bolt was one of the tbi mounting bolts, right next to the throttle bores.

 

[dlindsey19]

"And that scar looks deeper than .060" Did the machine shop already bore it?"

Agreed. https://www.summitracing.com/parts/sum-150100-30

That said, the rust in my TBI block didn't clear up with a .030" overbore, and the machinist and I decided it wasn't significant enough to worry about. Then again, if you're already at a .060" overbore and it doesn't clean up, you've introduced the most likely place the block is going to crack, and .060" overbores are sketchy at best.

They bored it and sleeved it too. I got the engine back yesterday and it seems fine to me. They also had to replace the number 6 connecting rod (probably bent it).

 

[dlindsey19]

Also, when they bore the cylinder walls 0.060" they're only taking out 0.030" from each side.

Ok

 

[Trlrider]

Your rebuilding that block?
Interesting, all the boring in the world is not going to fix the crack in the cylinder wall. Unless they are sleeving it, and at that point would have been better to find a virgin salvage yard block to build on.
And I seriously doubt the head that was on that back can be salvage either.
Better have a discussion with your machine shop before you spend any more money on that block.

Another good reason to carefully inspect mounting hardware, not just used, but new as well. Have found new out of the box head bolts that did not measure the same as the rest.

 

[dlindsey19]

Your rebuilding that block?
Interesting, all the boring in the world is not going to fix the crack in the cylinder wall. Unless they are sleeving it, and at that point would have been better to find a virgin salvage yard block to build on.
And I seriously doubt the head that was on that back can be salvage either.
Better have a discussion with your machine shop before you spend any more money on that block.

Another good reason to carefully inspect mounting hardware, not just used, but new as well. Have found new out of the box head bolts that did not measure the same as the rest.

As much as I’d love to get a new block and heads, budget didn’t really allow for it unfortunately. They were able to bore it and rebuild the heads with slightly (I mean slightly) bigger valves and valve springs and it’s been perfectly fine so far. Haven’t been able to get the engine in the truck but within the next week or two it should be running. I also can’t really turn back now as the heads are on it and it’s almost ready to go in the truck. But if they built me a block that doesn’t last, it has a 2 year, 24,000 mile warranty. So we will see how well it holds up.

 

[RichLo]

Did they document the rebuild with pictures for you? That's good they gave you a warranty. Watch very closely for blowby and oil consumption once you get it on the road again.