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LOL about heating the block to hone/bore.

I do wonder about this subject a lot... I imagine heat would make less of a difference than bolt force btw.

As to getting a plate - how about acquiring some plate aluminum, have it waterjetted (pretty inexpensive process in itself, generally), then have one side shaved flat by a machine shop? Materials and machine time probably come out to $150 maybe, but I dont know...
 

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Discussion Starter · #23 ·
I had a 1.5" steel plate waterjet cut. It was $200 for design, materials and the cutting. Plus shorter bolts. it worked great.
I had spoken to a FA shop about using theirs, was going to cost me the same plus a trip out of state. They used to do hot honing, but stopped because they didn't see any gains with the 4ag.
 

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8ton said:
I had a 1.5" steel plate waterjet cut. It was $200 for design, materials and the cutting. Plus shorter bolts. it worked great.
I had spoken to a FA shop about using theirs, was going to cost me the same plus a trip out of state. They used to do hot honing, but stopped because they didn't see any gains with the 4ag.
You could prob. rent your plate out and recover most if not all of your investment, I'm sure it would help other's like yourself out in the future.
A $200 deposit could insure they didn't just run off with it.
 

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Discussion Starter · #26 · (Edited)
'60s V8s and '80s Japanese 4 cylinders are not necessarily comparable. The casting tech greatly improved in a lot of ways, but the old stuff had a lot more 'meat' in the blocks.
I also note that in that link, no one had measured and said 'it changes X much, not enough to bother with' Just 'I eyeballed it, and it looked fine'
Measuring your own block will tell you for for sure. Mine moved around a ton. Maybe yours wont. It only takes an extra 20 minutes to check it (with and without the head torqued down)
All of the shops that specialized in 4ag's that I spoke to recommended using one.

I looked into using a head. If you have free access to a mill it may be doable (but I worried that the casting may come apart after one use). I have to pay for my time with the machine, Large hole saws are crazy expensive, and it worked out easier and cheaper to have a 1.5" steel plate Cnc water cut.
 

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Yea, I hear you. I don't doubt a torque plate could make a measurable difference, even to output. Although, all that sort of gain is all anecdotal also - the nature of competitive racing I suppose. However I wonder how a torque plate compares to a head. I also think the differences between torque plate and not is of trivial benefit to a street engine. Questions like, did Toyota use one to build the block? Also, valid points like comparison to variations due to internal operating stresses, thermal and mechanical.

Now with my block out, I suppose I could easily bolt my head on to check for myself. Was your block a 7 rib or 3 rib? I remember seeing a thread around here where you described your experience, but I can't find it now. You saw like .0015 change somewhere, as I recall...
 

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Discussion Starter · #28 ·
Go to the beginning of this thread.
I have a '90 smallport block-7 ribs with squirters, stock bore. It moved enough that my machinist was worried about ring longevity. Any extra power is just a bonus.
In the manufacture process, Toyota likely used some other method to 'pre-stress' the blocks. A torque plate takes a lot of time to bolt down to each block, the right fixture in the boring machine could do the same thing in seconds, millions of times over.
 

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Silly me, the front end of this thread discusses exactly what i linked...

.0015 difference in "ellipticity" (if that's a word)... Well, not sure what to think about that. Net .003 does sound worrisome...

Really? Toyota has a machine that stresses the block the same way but isnt basically an automated torque plate? I'm sure only head bolt loads would sufficiently duplicate the stresses in question. I'd love to see information confirming Toyota used any system to basically "torque plate" their production run blocks...

In my current application, I have a low mile engine that can probably get away with a deglazing "ball" hone, so i'm thinking whatever Toyota did, is still basically built into the block, and I'll be ok without a torque plate. Of course, I do want to avoid cost and trouble of a torque plate, and I'd use one if it was readily available at little cost...
 

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8ton said:
Go to the beginning of this thread.
I have a '90 smallport block-7 ribs with squirters, stock bore. It moved enough that my machinist was worried about ring longevity. Any extra power is just a bonus.
In the manufacture process, Toyota likely used some other method to 'pre-stress' the blocks. A torque plate takes a lot of time to bolt down to each block, the right fixture in the boring machine could do the same thing in seconds, millions of times over.

Did you check deflection with the mains bolted down? Was the crankshaft in place? I may check my deflection with my cylinder head bolted on - a lot harder to do with the crank in place...
 
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