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Hi gents,
 

I've done a lot of looking, I even posted on an old thread for clarification, but no dice. Yes there is bulk information on what gaps should be I'm all good with that, going with the manufacturers specs for my build. The one thing I have not seen clearly (Sorry if it has been sorted but I cannot find it) is the torque plate.

Now the right way to gap the rings is using a torque plate if the block was machined with a torque plate. and yes there will be an amount of inaccuracy gaping rings without one, but in all the ring gaping talk on here no-one really says if they were or were not using one at the time. It's my gut feel that most people who have gaped their own rings have not been using one. I don't have or have access to a torque plate, the one thread this was mentioned someone did ask if others were using one and there was 1 response saying that they hadn't so that's 2 people who ave gaped their rings without. That's not a big enough sample size. And if you are doing it without, is there a rule of thumb allowance for the gaping I have seen in other places where they discuss a 1 or 2 though increase in the gap to compensate for the torqued condition and having the rings close up a smidgen when the head is on. Or are the specs taking that into account. My gaps according to my use will be .007" per in dia with 86.5mm bores that's an ample gap of 23.8 rounded to 24 thou. (according to the total seal chart for medium boost 15-30PSI on E85). I feel like this gap if anything is a bit big and any shrinkage of that gap due to the distortion will never result in any sort of butting, my reasoning being many engines built for street and low boost application with much smaller gaps end up being turned up a long way eventually and n o-one bother to re gap their rings as a part of the big boost mods.

I do apologise if this is covered in detail somewhere, but the question on the torque plate for the guys building at home I just can't seem to find an answer for.

You are over thinking things.  There is a difference between out of round distortion and change in diameter.

Ring these people

http://pacificengineparts.biz/

Talk to Trevor about end gaps and more importantly blowby.

Or atleast leave a message for him and he will get back to you.

Thanks for your feedback, I know the difference, I'm just after confirmation as to what others have done and are doing. If it is out of round though it will affect how the ring sit, when gaping and affect that measurement, but like I said It's probably negligible.

4 hours ago, KiwiRS4T said:

I have only built about 4 or 5 engines with specified ring gaps and have never used a torque plate...not aware of any consequent problems...

I have built many engines in my lifetime, never used a torque plate when gapping rings, never had a failure. I'm careful but that sounds over the top.

There is absolutely no call for using a torque plate when gapping rings, unless you're talking Indycar/F1 level builds.

The distortion that happens in the bore walls when the head/plate is torqued up is in all 3 dimensions, and the most important ones, when boring or honing the bore, are the distortions that push or pull the bore material up & down, causing bulges.  But these are tiny tiny bulges, and I'm pretty sure there are few people and few feeler gauges accurate enough to measure them.  Your own measurement error and the acceptable tolerance on the measurement will be larger than the difference caused by the lack of distortions.  And that's not even taking into consideration what Bob said above.

5 hours ago, GTSBoy said:

There is absolutely no call for using a torque plate when gapping rings, unless you're talking Indycar/F1 level builds.

The distortion that happens in the bore walls when the head/plate is torqued up is in all 3 dimensions, and the most important ones, when boring or honing the bore, are the distortions that push or pull the bore material up & down, causing bulges.  But these are tiny tiny bulges, and I'm pretty sure there are few people and few feeler gauges accurate enough to measure them.  Your own measurement error and the acceptable tolerance on the measurement will be larger than the difference caused by the lack of distortions.  And that's not even taking into consideration what Bob said above.

That's what I thought thanks I'm off to gap my rings and continue building. Thanks guys for confirming it.

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