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Discussion Starter #1
we just got a 390 ford back from a local engine builder.
it was already .03 over and we went to .04 over and one of the cyls needed a sleeve.
the cyl that needed a sleeve is in the front.
I noticed that the sleeve is down about .01 from the top .is that ok?
he said the gasket would take care of it and that's no problem.
the sleeve is epoxied in with a press fit and it wont move he said.
does this sound normal?
also we checked all of the bores with a good boregage and they are all exactly .040 to .0405 over except one that is .042.
how does this sound?
this will be a 445 stroker motor and driven just on the street.
 

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I have never seen a sleeve below deck. The two questions I would consider

1 - Are you running a Felpro 1020? If you are, bore size is 4.40, if the fire ring is outside the sleeve, it should seal

2 - If yes, does the epoxied sleeve need to be supported from the top? I can't answer that question, but I think they should be trapped, but whether they need to is a different story

I personally don't like it and wouldn't accept it, but the question is will it last?

As far as the bore size, an extra .002 of clearance generally won't hurt anything and unless a ridiculous amount, with a forged piston you'll get a little cold temp piston slap, but it depends how loose they are. CnC piston machining is much better now, so pistons are more consistent, but I still like to finish hone to the specific piston that is going in the hole. I'd say measure every piston and if you can find one with a thou or so bigger OD, stick it in that hole.

Which pistons are you running?
 

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If I am reading this right and the top edge of the sleeve is .010 inches below the deck, you will have a very strange quench area that might encourage pre-ignition. Generally, you want to keep the quench area as small as possible in high compression engines for this reason.

When a sleeve is installed they generally leave it sticking out of the bore slightly and then cut the deck flat.
 

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Discussion Starter #4
after a bit of haggling he said to bring it by and he would deck it to the surface of the sleeve and then take the same from the other side.
he said he thought we would be back to have it decked after we put the pistons in and measured if they were even at the top.
he said he went too far with facing the sleeve down because it was hard for him to see and even though it was below the surface .012,he thought we were going to have it decked later.
ill drop it back off next week and report back here!
also check out this huge chamfer at the top of the sleeve.it is 3 times the size of the chamfers on the other cyls.this leads me to believe that possibly the sleeve was brought to length before it was pressed in and there was a miscalculation.


 

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Sounds like a CYA story, but as long as he is willing to fix it, sounds like it'll be OK

If you know all this stuff, forgive me for the book, but trying to give some options

The reason I don't like his story is because measuring the pistons in the block is a bit goofy. He should have squared decked it to the mains and met a spec, measuring a rocking piston in a crooked deck is not precise, but CnC machining of parts today is generally a bit closer. Not all machinists do that, but that's what we do to blueprint something and make all corners the same. Most FEs tend to be all over the place.

Now doing BOTH (calculating and checking) isn't bad, as it makes sure your new components are what you think they are, but I haven't seen any in modern parts.

I'd recommend you calculate yourself before you go any further. Barry's custom Mahles are designed for a 10.160 deck, regular Mahles are designed for a 10.155, Probes are 10.155, and if he cuts too far, you'll be fighting deck clearance. Most 445 pistons are designed for 10.155 decks.

To calculate your required deck height, first calculate the stack height of the reciprocating pieces, piston, rod, stroke. 1/2 of stroke (2.125) + rod length (6.70) + compression height (depends on brand and design, get off the piston box)

That number is likely better than measuring it in the bore if your machinist can hit a target, and in a perfect world, that number = the number he square decks to

If he cannot square deck to that number, or has to cut more, then see how far above deck the pistons are, and pick a head gasket that gets you to no less than .037 and preferably no more than .050.

That being said, IF it ends up too short, Felpro 1020s are .041 and could handle pistons that are up to .004 above deck, and a Felpro 8554 (blue gasket) can handle pistons up to .014 above deck.

Example of pistons above deck - calculated stack is 10.160, he cuts to 10.155. You are .005 high, Felpro 1020 gasket is .041, that's .036 clearance, that is right on the edge (but could be run with a low RPM engine). Felpro 8554 is .051 thick though, so subtract your .005 and you are at .046, which is right on the money for a street/strip motor

Example of pistons below deck - Stack is 10.155 and he cuts to 10.158, you are .003 low, add the Felpro 1020 (.041) and you get to .043, perfect. In this case, the 8554 would be .051 + .003 = .054. That is OK for a stocker but I'd go Felpro 1020.
 

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Discussion Starter #7
I actually am a machinist. just not an automotive one.
you said I can calculate the deck height.
I am buying the stroker kit from barry.
is there a way that I could measure somehow the deck height now?
does this come from the center of the crank journals to the top of the block at the piston holes?
this motor was already .03 over when we opened it so I cant say for sure if it was decked before.
 

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So you can measure the block through the bore using a 12 inch caliper, it'll get you very close if you are careful, and then you calculate the reciprocating assembly (stack) height as mentioned above.

10.170 is stock, but you have to measure to the main bearing saddle and then add 1/2 the main bearing bore size to get you to the number accounting for theoretical crank centerline.

If you were really fancy, you could make a slug that coult be bolted between two main caps and is drilled to exactly 1/2 depth and measure from deck to the bottom of that hole, but sorta overkill for what you need to know.

Be sure to measure at least all 4 corners, so you know which the shortest part of the deck is

Once you know what is possible, most modern shops nowadays can center their machine on crank centerline and hit the number you ask for. My last one I just told my machinist to make it 10.160, one deck got barely cut, you could still see staining, the other side got a decent cut

Good idea to measure ahead of time though, because Barry can easily get you pistons designed for a 10.160 or 10.155 deck, and if you were really in an odd place, Brent Lykins does a lot of work with Racetech and can get pretty affordable pistons in any dimension you want
 

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Discussion Starter #9
we picked it up last night and he said it was within the specs of the deck height we gave him.
I know he didn't go too far because it still has the large chamfer on the sleeve.
he actually seemed to have a bit of an attitude about it.
the block is now filled with grit again and he didn't even attept to clean or wash it at all.
the tops of the cylinders are razor sharp so I guess we will have to somehow chamfer these ourselves.
now our big problem is that when we took it to him we had to disassemble the engine quickly just before we brought it to him.we put the main caps back where we removed them from and we assumed they were stamped or numbered somehow.he gave us everything back in a box and we cant see any markings on the caps at all.
is this going to be a major problem?
it was noisy in our shop today and I planned on calling barry tomorrow to order the stroker kit.
 

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we picked it up last night and he said it was within the specs of the deck height we gave him.
I know he didn't go too far because it still has the large chamfer on the sleeve.
he actually seemed to have a bit of an attitude about it.
the block is now filled with grit again and he didn't even attept to clean or wash it at all.
the tops of the cylinders are razor sharp so I guess we will have to somehow chamfer these ourselves.
now our big problem is that when we took it to him we had to disassemble the engine quickly just before we brought it to him.we put the main caps back where we removed them from and we assumed they were stamped or numbered somehow.he gave us everything back in a box and we cant see any markings on the caps at all.
is this going to be a major problem?
it was noisy in our shop today and I planned on calling barry tomorrow to order the stroker kit.
It's an issue if you mix up main caps, but they should be marked.

That being said, rear main is unique, as is #3 (center) with the thrust bearing groove. FYI caps go together tang to tang (both bearing tangs up against each other for all bearing caps

After that, the diamond on the top of each cap should have a mark from a punch. One mark is the front cap, two punches is #2 and 4 punches is #4. Again, tang to tang on all bearing and rod caps

BTW, this guy sounds like a winner, my guess is he just lopped off the top, so my recommendation, buy either compression height piston. If it is above deck at mockup, buy an 8554 Felpro, if it is below deck, run a 1020 Felpro head gasket
 

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FYI not sure why I called it a diamond last light, it should be a small triangle in the center of the cap.
 
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