Torque plating cylinder block

[evopwr]

I'm finding conflicting information regarding torque plating requirements when machining cylinder bored for oversize application.

Some sources say: necessary.

However a machine shop I've recently visited state this is only a necessity where head stud/bolt holes are very close to the cylinder walls (e.g. V8s). On 4cylinder engines such as the 4g63, the stud holes are positioned far enough from the bores that torque plating will not significantly assist in tighter out-of-round tolerances.


Any comments on this? I understand it's a nice one to have but is there any comparisons out there?

 

[GeoKez]

It's a interesting question. Torque plating the cold bare block doesn't really replicate it's 'shape' when it's all bolted together at op temp and load does it. Surely the crank bolted in would effect the shape when all torqued up? Same with heat expansion when at temp opposed to cold? I think the theory is sound for all block types, but are the methods used by your average machine shops providing any practical benefits? Who knows....

 

[evopwr]

So many variables involved. I don't even think it's possible to measure cylinder bore warpage once everything is bolted up at cold start & operating temps...

 

[4piknup]

Mains caps are meant to be in and torqued.

better than not having it done. Worthwhile imo.

 

[bazeng]

Yes. A must. I've measured before and after is there is a significant difference.

If you need a torque plate you are welcome to borrow mine.

 

[DOUGMO]

yep, must do, and when done torqued to the torque you will use when bolting it down.

as George points out a warm block would be better but its better than not

 

[blackvr]

Have you felt the temperature of the blocks when they bore and hone them.....In fact, they have to slow things down in case the temperature of the block rises too much. And for the record, all of my builds are B&H'd with a torque plate. You can measure the difference

 

[evopwr]

Sweet thanks guys. Baz I may require your services in the not-too-distant future!

 

[GeoKez]

You see, the good thing about this forum is that when you say "Who Knows.....", plenty of people actually know shit. Good info.

 

[evopwr]

You see, the good thing about this forum is that when you say "Who Knows.....", plenty of people actually know shit. Good info.

Very difficult to find a forum with this type of knowledge/resource these days!

 

[4piknup]

I wish someone knew about nissans consult2....

 

[GeoKez]

All I know about nissans Jack, Is that they do a good job of keeping fuckwits out of evo's.
:hiding:
:bongs:

 

[evo-gsr]

Bongs?? ^

 

[4piknup]

I think he means boongs^

 

[BMGTZ]

boongs with Bongs....

 

[GeoKez]

It was supposed to be :ninja: but somehow iStupid gave me bongs on spell check.

 

[4piknup]

Fingers getting fatter geo

 

[GeoKez]

The fingers are just keeping up with the rest of me Hack

 

[4piknup]

At least h is next to j. And you did capitalise.

 

[evo-gsr]

Think he was referring to some of your custom work = Hack.
(Lol!)