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If a block has been torque plate honed, would it be normal for the block to exhibit a couple of thousandths of out of round and / or taper when measured without the torque plates installed. The specific block is an aluminum Teksid 4.6L modular Ford. Would one have to measure the bores with the torque plate installed to get accurate measurements?
Yes this is quite normal. For the torque plate to be able to do anything it would infer that the block is out of round when the torque plate is fitted. Naturally if the block is then bored and honed and the torque plate removed we can expect the block to move slightly and the bores will no longer be perfectly round. To get accurate measurements you will need to install the torque plate if that's how the block was bored/honed.
Thank you. That’s what I thought. I had it honed with torque plates at the machine shop; I think I will need to trust that the bores are correctly sized. I can’t justify spending $500 on torque plates to check the work. They measure a maximum of .004” out of round without the torque plates installed.
For the main bearing clearance I bolted the heads on and torqued them to spec and I did notice about a .002” difference compared to not having the heads bolted on. They were much closer to perfectly round with the heads bolted on.
An alternative to the torque plate is to bolt the heads to the block and measure the bores from underneath.