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Went to the local machine shop after work tonight to get some prices on engine machining.The owner is a former drag racer and gear head and has been building motors all his life,but it is a basic type of machine/engine rebuilding shop,nothing fancy.I asked about boring and honing,no problem,asked if he uses a head torque plate and he said that they have never used them.But they do put the main caps on and torque them,been doing it this way for 50 years and never had a problem.He said they use a 700 finish hone,is this good for a plasma ring?Also asked about align honing main caps after installing an ARP stud kit,he said he doesent have a machine to align hone,but can align bore,but that he would measure the main caps with the stud kit installed to check for roundness,and then proceed as necessary.I also asked about having new ARP rod bolts installed,and he said that much the same would apply,check measurements and proceed accordingly.His thinking is that ARP suggest you align hone main journals because if someone is putting a stud kit in chances are they were having problems somewhere.Does all this sound reasonable?This shop has an excellent reputation around here,they have been in business as long as I can remember!His prices seem pretty good,and its close,looking for some thoughts on this matter!!!
 

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He is correct on line boring the main saddles. Wholesale line boring just because the motor is using studs is not always good. Each block is different. Different blocks react to the clamping force of a stud. Check for alignment and total out of round.

Not much of a high perf shop tho. If he doesn't do t-plate honing. SBC's in general require it for round bores. Otherwise the top of the bore distorts to a Pentagon shape as the head bolts are tightened. Round rings-Pentagon bore=Lots of lost compression.
 

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For a shop that claims to high performance work and no torque plates and no line hone table WOW we deal with shops all over the U.S. and a couple of guys in Canada and they are doing what I call performance work.

We have had some engines on the dyno that other shops have built and it doesm't take long to fiqure out that is was not honed with plates by the amount of blowby at WOT where not the biggest shop in the country but we do have some of the best equipment going.

It's one thing to check the bores for roundness another to check to see if they are in line with each other as we have 2 line hone tables on at each shop and every block that goes through our shops is line honed and playe honed as well and squared and decked.

Here is a link we did a few years ago on what it takes to truely blue print a block.http://www.chevelles.com/forums/showthread.php?t=93124
 

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Anybody who doesn't realize or understand the benefits of torque-plate boring and honing is probably not up on other important building and machining processes.

tom
 

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Nearly everyone uses plates. I think most are not using them properly. They torque them on and start honing. Just my opinion, but I believe you should have the heads and bolts that are going on the block to determine the amount of bolt that will actually be in the block. If you use a plate with different length bolts it will distort the block different than when the heads are bolted on and might do more harm than good. I see guys using any bolts they have lying around. I watched an "engine builder" use a bolt that was too short on my new Merlin block. When he torqued it, he pulled out the top four threads :spank: :boxing: :mad:
Bob
 

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Agreed that the amount of thread in the block is important. Ford had a problem with the 302 back in the 1980s -- couldn't get oil usage to meet their standards -- and after chasing valve guides and seals for a couple of years they finally narrowed it down to distortion in the #8 cylinder bore related to head bolt distortion. I no longer recall the exact circumstances... I think one bolt was longer or shorter than the rest for some reason.....
 

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pmeisel said:
Agreed that the amount of thread in the block is important. Ford had a problem with the 302 back in the 1980s -- couldn't get oil usage to meet their standards -- and after chasing valve guides and seals for a couple of years they finally narrowed it down to distortion in the #8 cylinder bore related to head bolt distortion. I no longer recall the exact circumstances... I think one bolt was longer or shorter than the rest for some reason.....
There were a couple of problems that you are touching on for the 302. The # 8 cylinder problem you mention was caused by the PCV valve vacuum source being located right at the #8 intake runner, causing oil to be pulled into the #8 cylinder. Relocating the PCV vacuum source was the fix for that problem.

The other problem was that the intake manifold would pull the heads away from the deck on the intake manifold side of the block. The fix was (is) to torque the inner (upper) head bolts to 80 ft. lbs. and the outer (lower) bolts to 70.

tom
 

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Bob C said:
Nearly everyone uses plates. I think most are not using them properly. They torque them on and start honing. Just my opinion, but I believe you should have the heads and bolts that are going on the block to determine the amount of bolt that will actually be in the block. If you use a plate with different length bolts it will distort the block different than when the heads are bolted on and might do more harm than good. I see guys using any bolts they have lying around. I watched an "engine builder" use a bolt that was too short on my new Merlin block. When he torqued it, he pulled out the top four threads :spank: :boxing: :mad:
Bob
At our shop if we are torque plate honing a block for another shop or engine builder we have them fil out a spec sheet and we duplicate what they are using a s far as hardware and gaskets and the 010 blocks different head gaskets make a differance in cylinder distortion.

On the Darts and Bowtie blocks its hard to see a measurable differance plate honing unless you are out near max bore.

Even on the main caps we send torque specs and the lube we used as we have found there is a measurable differance there as well.
 

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Discussion Starter #9
I guess that I'll look into another machine shop,I definetly want my block bored and honed with torque plates.This shop is right here in town,but they are just a basic engine rebuild/machine shop.We have another top quality shop in the area,its just a little farther away and probably more expensive.Thanks for the help!
 
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