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Old 09-24-2011, 08:33 PM   #1
Team Scream
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Default ARP vs OEM case bolts - The real story.

I decided to prove this out myself, and do back to back tests using stock and ARP case bolts on the same set of case halves.

First a little test/set up data.

All of my mics are Mitutoyo, I keep them clean, and have never dropped them. My bore gauge is a Fowler and is accurate to .0001, and indicates to .00005

I live in California, near the beach and it is almost always right around 70*f
Today is is 67*f, overcast, and "June Gloomy" (even though it is September).

2006 STi short block that had 43K on it when I got it for parts. No spun bearing, but did have a broken ring land on cyl.#3

I took the crank to my local machine shop and had them use a brand new polishing belt to get me a nice clean finish on all journals after I checked them for roundness and size, I did not have them polish to any particular size, I just wanted a nice finish for this test.

The case halves were cleaned, bolted together with ARP case bolts, using the ARP lube which is supplied with them. ACL race bearings, cleaned, deburred edges etc. were installed. The cases were torqued in the order outlined in the FSM, in 3 equal steps to 70 ft/lbs as indicated by ARP TECH SUPPORT.

OK MAJOR EDIT/Update HERE !!!! Because I misplaced the sheet that came with these bolts when I bought them, I had to call ARP to get the torque VALUE and SEQUENCE. The rep on the phone specifically told me 70 ft/lbs on the 10mm bolts, and 22 ft/lbs on the 8mm bolts, and DO NOT DEVIATE from the FSM as far as torque sequence goes.

This was based on OLD information that ARP used to publish with their case bolt kit. The new published value is 60 ft/lbs. It should also be noted that the SAME tech support guy told me to torque the ARP head studs to 80 ft/lbs. which was proven to be incorrect by ASF Machine as you will see below, based on his scan and posting of the sheet that comes with the 260-4701 head stud kit that indicates 90 ft/lbs.

The 260-5401 CASE BOLT KIT comes with a sheet and has published torque values of 60 ft/lbs for the 10mm bolts and 25 ft/lbs for the 8mm bolts, and states to reuse the 6mm bolt on the bottom of case (which gets covered by the oil pan) and torque that bolt to 5 ft/lbs.

This sheet also describes a specific method/sequence for installing the 10mm bolts.

The ONLY thing the guy did NOT get wrong was torquing the bolts in 3 equal steps to final torque.


Lets get back on topic here.

I mic'd the crank journals (post polish) and here are the measurements:

#5- 2.36170
#4- 2.36195
#3- 2.36210
#2- 2.36210
#1- 2.36100

This is my work bench for "dirty" work (small and convenient):




I set the mic against each crank journal and then used it (the mic) to set zero on my bore gauge. I then measured each bearing in 3 places, 90* from the split line (center) and 1" (approx.) either side of the 90*.

The results are the oil clearance that I would have:

#5
@ center.- .00045
@ 1" top - .00180
@1" bot - .00240

#4
@ center- .00215
@ 1" top- .00220
@ 1" bot- .00235

#3
@ center- .00130
@ 1" top- .00170
@1" bot- .00080

#2
@ center- .00142
@ 1" top- .00135
@1" bot- .00225

#1
@ center- .00087
@ 1" top- .00080
@1" bot- .00045

The bearings are not round, and the clearances vary significantly.

Next, I carefully un-torqued the case bolts, and then installed clean, oiled, OEM case bolts and washers, and torqued the case bolts using the method described in the 2006 FSM.

Here are the results of that operation (again, oil clearances are given):

#5
@ center- .00080 (difference = (+) .00035)
@ 1" top- .00150 (difference = (-) .00030)
@1" bot- .00180 (difference = (-) .00060)

#4
@ center- .00240 (difference = (+) .00025)
@ 1" top- .00215 (difference = (-) .00005)
@1" bot- .00280 (difference = (+) .00045)

#3
@ center- .00190 (difference = (+) .00006)
@ 1" top- .00200 (difference = (+) .00030)
@1" bot- .00180 (difference = (+) .00010)

#2
@ center- .00180 (difference = (+) .00038)
@ 1" top- .00220 (difference = (+) .00085)
@1" bot- .00240 (difference = (+) .00015)

#1
@ center- .00100 (difference = (+) .00013)
@ 1" top- .00160 (difference = (+) .00008)
@1" bot- .00155 (difference = (+) .00110)


Here is a another picture showing my method(s) Basically I mic the crank (3 places per journal) and lock the mic.



Then I zero the bore gauge using the mic. It is extremely important to keep the mandrels of the gauge perfectly centered between the mandrels of the mic to get an accurate setting on the gauge. This is why I use a digital bore gauge and not a dial. Hitting the zero button on the bore gauge is way easier than rotating a dial while trying to keep the gauge centered on the mic.




Then I measure the bearing that corresponds to the journal I set the mic to, in 3 places. Because they are split bearings, the reading at the split is inconsequential unless there is too much crush and the bearing deforms so much that you end up with zero clearance. I always check at the split to confirm I am oversize but the reading is not documented here.








I do go through the trouble of measuring each journal individually, and then recalibrate the bore gauge to each journal, primarily because they are not ground identically to the same dimension. Obviously it would be way easier to mic all the journals, discover they were all within .00001, and go from there, but our cranks do not seem to be that close (at least the several I have measured anyway).

People in the Subaru community seem to do things a little differently than I am used to when it comes to bearings and cranks.

As an example, when we built 800hp twin turbo race motors for Nissan back in the 80's, the cranks were all custom, precision ground so that each journal was exact to .00005, and oil clearances were obtained by polishing the back sides of each bearing accordingly. Here (Subaru) the rule of thumb seems to make the crank the sacrificial lamb so to speak.

The "rule of thumb" procedure would never work in a full blown race environment where rebuilding an engine in a race trailer or hauler happens on a regular basis. In that scenario, you need to be able to pull a new crank off the shelf, know that it is to spec, and adjust bearings to get the required clearance. Cranks were also north of $10k back then, so grinding one after the fact was heresy.

I am reasonably certain that my attention to detail is far greater than any of the (automotive) machine shops in my immediate vicinity. And I am also very confident in my methods. I get good repeatable results the way I do it, so I have stuck to it for many years now.


Anyway, back on topic here.

It is obvious that the ARP bolts push the main webs around a bit when torqued to ARP spec. The bummer is, a standard align hone is not going to "solve" the problem. At least not make it "perfect" from what I can tell.

There is a lot of variation in both examples. The ARP bolt example puts me at minimum clearance on the #5 bearing @ the center point, and beyond acceptable limits off center. The #4 bearing is right at the edge of max tolerance, it is actually slightly over, but I would run that on a street engine.

Even with the stock case bolts, I am oversize on the #2 and #3 bearings, but again, on a street engine, it is not so big that it would cause any issues an extra shim in the oil pump could not manage as far as pressures go.

I am pretty new to Subaru engine building, and my old school, anal, worked in an ultra high end race shop mentality has me striving for perfection, but everywhere I turn, I find limitations imposed by the basic design of the platform.

At a certain point I just have to step back and realize that I am not going to get perfectly round mains, and that spending 20 hours polishing a crank or bearing shells is not really going to net me a whole lot.

My goal for this build was hit the loose end of the FSM tolerance for the mains, and .002 on the rods.

The crank is super close, so buying a new crank and starting from there does not make any sense. I think that mixing and matching bearings, combined with creative polishing of the crank can get me there.

Hope this helps someone else out when it comes to a home build.


EDIT for ARP @ 60 ft/lbs torque


Ok so got the new chair.... lol

Took the OEM case bolts out and installed the ARP bolts, then carefully torqued them to 60 ft/lbs in 3 equal steps (20/40/60 ft/lbs) like i have done throughout this process.

Here are the findings. As a side note it should be stated that it is actually 4*f hotter than it was yesterday when I started this test. As a precaution, I re-checked the crank on all 5 journals to confirm that it did not grow from yesterday to today's test. All 5 journals measured the same. The tools, crank, block and bearings were all left on the bench in the same environment as they were yesterday. This is as good as it gets in my opinion, when trying to do a reasonably controlled test.

If it were 10-15*f difference in temperature, then I would think there could be some discrepancies, but in this case, 4* does not appear to make a difference, and since ALL components have been in the same environment throughout the test procedure, I conclude the test is valid for all intents and purposes.

Results of the 60 ft/lb torque test (oil clearances given):

#5
@ center- .00040 (difference= (-).00005)
@ 1" top- .00130 (difference= (-).00005)
@ 1" bot.- .00120 (difference= (-).00120) <---- significant!!!!!!

#4
@ center- .00020 (difference= (-).00015)
@ 1" top- .00150 (difference= (-).00005)
@ 1" bot.- .00250 (difference= (-).00015)

#3
@ center- .00080 (difference= (-).00050)
@ 1" top- .00080 (difference= (-).00090)
@ 1" bot.- .00010 (difference= (+).00020)

#2
@ center- .00100 (difference= (-).00042)
@ 1" top- .00120 (difference= (-).00015)
@ 1" bot.- .00170 (difference= (-).00055)

#1
@ center- .00100 (difference= (+).00023)
@ 1" top- .00170 (difference= (+).00090)
@ 1" bot.- .00140 (difference= (+).00095)

<EDITED FOR ACCURACY> My initial statement here was that torquing the ARP bolts to 60 ft/lbs did not improve the situation, Later findings show that to be incorrect!
See post #69 for my final results.


I also noticed something that I wanted to corroborate with yesterdays findings.

The #5 (thrust) bearing is unique in this engine design, in that half of the bearing shell is inbound from the center-line of the rear most 10mm bolt on the passenger side of the engine, and seems to suffer the most from the increased clamping load these ARP bolts induce on the case structure.

As a result, the #5 bearing actually gets twisted in it's bore from what I can tell.

The bearing itself has 2 bearing surfaces with a significant groove down the middle for oil flow. When I measure the front most portion of that bearing, I get a completely different reading than I do when measuring the rear portion.
The discrepancy is between 2 and 3 tenths depending on where I take the measurement from.


Let's discuss align honing for a minute.

My take on it is it needs to be done in VERY VERY fine steps, and it needs to be done from BOTH ends of the assembled engine case.

In other words, the machinist needs to run the bar from front to back for the initial pass, and then flip the engine and run the bar from back to front for the final pass.

I think this is the only way to get a perfectly straight/perpindicular to the cylinder bores finish.

That action of flipping the case should eliminate any taper, but the act of flipping means he has to be extremely precise on the set up for the final pass or he runs the risk of making an egg instead of a perfect circle.
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Last edited by Team Scream; 10-03-2011 at 03:08 PM.
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Old 09-24-2011, 11:09 PM   #2
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bump ..
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Old 09-25-2011, 04:54 AM   #3
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I have found the same problems as you mentioned and have therefor one set of casebolts on the shelf. I ended up not using them as the ARP distorts the journal holes way too much. Align honing isn't gonna solve the problems because the distortions are too large.

Good luck to you and let me know if you have found a "proper" solution

Jasper.
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Old 09-25-2011, 05:50 AM   #4
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That' s a nice bore gauge and mics. After my engine dies from my crap build (I'm learning), I think I'll pick those up.
I'm a bit nervous now as i didn't get quite the same distortion as you. I hope I measured correctly
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Old 09-25-2011, 12:08 PM   #5
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this investigation really goes above and beyond my friend.

i am building a new engine and cant wait to share this with my builder.

we decided to go with a new crank instead of cutting my used crank. i wonder what we will do now.

it seems to me subaru engines suffer from bearing failures quite often. some blame bad tune, some blame bad oiling...i think this excercise in precision opens up some blind eyes in engine building techniques.

i applaud you taking the time to share your discoveries with our community.
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Old 09-25-2011, 12:23 PM   #6
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This is basic blueprinting.
I don't know that it'll blow anyone's mind.

OP: I appreciate the time it took you to do this and share.

I have found that with bearings available from -.025mm (-.001") to standard up to +.050mm (+.002") one can get it "gnat's ass" right nine times out of ten. Without using a polishing belt to make a slightly smaller, less round main journal.

The ARP issue is a tricky one and it's tough to find someone who knows how to align hone an EJ block without ruining it.

Last edited by ASF Machine; 09-25-2011 at 12:42 PM.
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Old 09-25-2011, 01:14 PM   #7
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Quote:
Originally Posted by ASF Machine View Post
This is basic blueprinting.
I don't know that it'll blow anyone's mind.

OP: I appreciate the time it took you to do this and share.

I have found that with bearings available from -.025mm (-.001") to standard up to +.050mm (+.002") one can get it "gnat's ass" right nine times out of ten. Without using a polishing belt to make a slightly smaller, less round main journal.

The ARP issue is a tricky one and it's tough to find someone who knows how to align hone an EJ block without ruining it.
^+1^ After messin around on a few builds I bit the bullet and ended up with about six sets of bearings, under, STD and over for the rod and mains. With creative picking and patient e for doing the torque procedure a few times you really can get everything right on without messing up the round factory journals or compromising any surface treatment/ nitride that might be present.
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Old 09-25-2011, 01:16 PM   #8
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so what distortion do we typically see with using oem block bolts?

from my experiences most people opt for arp head studs but use oem block bolts...

an arp head stud write up in the same fashion would be tits.

although on a forum of this magnitude i am sure if i searched i would find...
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Old 09-25-2011, 02:07 PM   #9
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Quote:
Originally Posted by ASF Machine View Post
This is basic blueprinting.
I don't know that it'll blow anyone's mind.

OP: I appreciate the time it took you to do this and share.

I have found that with bearings available from -.025mm (-.001") to standard up to +.050mm (+.002") one can get it "gnat's ass" right nine times out of ten. Without using a polishing belt to make a slightly smaller, less round main journal.

The ARP issue is a tricky one and it's tough to find someone who knows how to align hone an EJ block without ruining it.

/\ that is my biggest fear right now. I have my own torque plate for post machining validation, and in fact I even require my machine shop to use my torque plate when honing the bores to keep things constant. Right now my bores are exactly where I wanted them with regards to p/w clearance with the pistons I am using.

Now if I take the case halves back and ask them to align hone it, and they ruin it, I am screwed.

I spent a lot of time de-burring and removing casting flash, chasing threaded holes, and having the deck resurfaced. I figure I have about 14 hours of my own time into block prep at this point. It would be a real bummer to have it screwed by a poor align hone.

I have had bad experiences at 2 (supposedly) reputable machine shops/builders and both times when I checked the work they tried to charge me for, they were not even in the ballpark, let alone within 1 or 2 tenths.

An example would be:

I drop off a crank, rods and bearings and ask to have it (the crank) polished to allow .002 oil clearance.

I give them a target of .0020" +.000/-.0003 .
That means they can make it .002, .0019, .0018 or .0017
A good machinist will mark the rods, assign each bearing to a rod (mark them), and do one at a time until they hit a mark within that range.

I go and pick up the parts, take them home and clean everything up nicely.
Break out my mic and bore gauge to find that 2 rods/journals will provide .0010 and 2 will provide .0016 clearance.

Needless to say, I got my money back and now use a different place.
I wont even give that place a 2nd chance to make it right, because when I walk in the door the first time, I make it crystal clear I know what I am doing, I am going to check their work, I have good tools and am capable of doing so. If they deliver anything less than what they told me they were capable of delivering, they are incompetent from my perspective and will not get my (future) business.

I am finding that my experiences are totally commonplace out here.
There are machine shops who assume nobody is capable of or will check the work they are being paid for, and therefore will deliver whatever they feel like doing at the time. Unsuspecting customers pay the invoice, attempt to build the engine without checking/confirming, and spin or lunch a bearing 1000 miles into the tuning process.

Lets talk about plastigage for a minute while we are at it.

I also took the time to plastigage the mains with the ARP bolts just as an exercise. I was not going to share that info because I thought it was a bit inconclusive.

Same crank, same case halves, same torque procedure.
I wanted to compare the plastigage results against conventional measurements. What I found was that plastigage is not a very good method for determining clearance when the holes are not totally round.

In the picture below, you can see that on the #4 journal where the actual measured clearance was .00215", the plastigage indicates LESS THAN .0015"

The rest of the plastigage samples were displaced beyond the marks available on the scale (provided on the package), even though they should have provided evidence or a reading near .0015 (#2 and #3 journals), which is one of the marks on the plastigage scale.



My conclusion (for this example) is that plastigage would have you chasing your tail around in circles.
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Old 09-25-2011, 02:18 PM   #10
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Old 09-25-2011, 02:28 PM   #11
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"I drop off a crank, rods and bearings and ask to have it (the crank) polished to allow .002 oil clearance."

a reputable engine builder near me using this same clearance. the oem spec clearance range is a joke.

i am also diving deep into this investigation because frankly a plasigauge seems like the "good enough" method of assembling engines.

any work performed by you on the oem block bolt tolerances?

is the bearing manufacturer a variable to consider? i know ACL is reputable but they are not the only brand. only brand with trimetal finish?
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Old 09-25-2011, 02:35 PM   #12
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Quote:
Originally Posted by maxpowr View Post
a reputable engine builder near me using this same clearance. the oem spec clearance range is a joke.
i am also diving deep into this investigation because frankly a plasigauge seems like the "good enough" method of assembling engines.

any work performed by you on the oem block bolt tolerances?

is the bearing manufacturer a variable to consider? i know ACL is reputable but they are not the only brand. only brand with trimetal finish?
Im not sure I understand the question brother, sorry?


Quote:
Originally Posted by maxpowr View Post
so what distortion do we typically see with using oem block bolts?

from my experiences most people opt for arp head studs but use oem block bolts...

an arp head stud write up in the same fashion would be tits.

although on a forum of this magnitude i am sure if i searched i would find...
If you are going to use ARP head studs, you ABSOLUTELY must provide the head studs to your machine shop, and be reasonably certain they will follow the proper (as prescribed by ARP) torque procedure when honing the cylinders. It is also advisable to have them use the same type of head gasket you plan on using between the torque plate and the deck, to eliminate variables.

That procedure is 3 equal steps to a final torque of 90 ft/lbs using the ARP lube.

90 ft/lbs is more than twice the factory torque spec, so without question, there will be cylinder distortion as a result of the increased clamping load imposed by the ARP bolts, and the fact that to achieve proper stretch for those bolts, 90 ft/lbs is the mark with the ARP lube applied to the threads AND washers.

Then, you need to check the work using a torque plate. You cannot measure bores that were honed with a torque plate, unless you have the torque plate (and head gasket) installed.

As you can hopefully see, there would be no way to do a back to back test, because you will get completely different results if you try to use OEM head bolts on an engine case that was honed with ARP studs.

If however, you install ARP head studs on an empty case using a torque plate, you will definitely see more distortion with the ARP studs compared to OEM bolts.

Do NOT install ARP studs on an engine just because it sounds like a good idea. You must have it honed with the ARP studs and a torque plate.
I don't care what anyone else says, that is a definite no-no.

Last edited by Team Scream; 10-03-2011 at 02:54 PM.
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Old 09-25-2011, 02:38 PM   #13
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Quote:
Originally Posted by maxpowr
so what distortion do we typically see with using oem block bolts?

from my experiences most people opt for arp head studs but use oem block bolts...

an arp head stud write up in the same fashion would be tits.

although on a forum of this magnitude i am sure if i searched i would find...
The ony way to find the distortion with OEM bolts would be to buy a brand new case, and new bolts and tq them to spec. IMO you shouldnt see more than a few ten thousanths.

As for stock head bolts, even they distort the bore when torqued to spec unless you use a tq plate when honing. So measuring the distortion of arp head studs is sort of moot.
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Old 09-25-2011, 02:57 PM   #14
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these are the answers i am looking for...

i dont think i am alone in my curiosity, not being as versed in motor building as you guys.

i dont take anyones word as bible, but being in the process of rebuilding due to damamged bearings i am in search of information along these "lines"...or "bores" in this "case"...lol.

its been said that if you use new case, new oem 08 nitraded crank, acl hx bearings and manley turbo tuff rods, you will be within .0020 95% of the time.

i didnt see how that could be possible with the variances in mass produced oem and aftermarket parts.
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Old 09-25-2011, 03:25 PM   #15
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Quote:
Originally Posted by maxpowr View Post
its been said that if you use new case, new oem 08 nitraded crank, acl hx bearings and manley turbo tuff rods, you will be within .0020 95% of the time.

i didnt see how that could be possible with the variances in mass produced oem and aftermarket parts.
Well, (so far) it is my experience that you can never assume anything is close enough for sustained high rpm use in an opposed 4 cylinder engine with regards to buying parts and throwing a build together.

I think the forum is littered with people who have successfully proven that concept totally wrong and inadequate. Examples are everywhere, spun bearings, thrown rods etc. etc.

If you are building an engine yourself, and you do not have at least 3 things:
(1) Bore gauge, (2) 2-3" and (3) 3-4" mic, you are tossing the dice. Hopefully you don't crap out.

Furthermore, you can probably buy a new OEM crank, and a set of bearings and you might get close, but remember, Subaru manufactures the cases with different main journal bore sizes.

If you look at the service manual, they stamp each case with letters for bore size on each side, AND they stamp numbers for main journal size for each journal.



On my particular engine, here are the marks:



I admitted earlier that I am new to building Subaru engines, and I am still not certain if those marks denote crank journal size, or actual crank journal bore size on the case itself. I am assuming crank journal bore size.

So no matter what, unless you get one that is 22222, or 11111, there are going to be differences, and if you just try to piece an engine together without checking, you have no idea where you are at, and consequently when it fails, you have no idea why.

Then, you get demoralized, blame the platform and lose faith.

I think there is only one way to do it, and that engine builders like Micah, Dom, ASF etc. who actually spend the time to truly blueprint their engine builds deserve the money they charge.

This crap takes a LOT of time to do it right.

Us mere mortals out here in the real world have to rely on machine shops to hit the mark for us, and if we do not check their work, we cannot whine and cry when we toss a rod, spin a bearing or stick a piston.
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Old 09-25-2011, 03:26 PM   #16
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I have a block we just had sleeved from darton east here. We also had it align honed. I'll have to post up my results from our measurements for everyone.
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Old 09-25-2011, 03:43 PM   #17
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this is why this thread has me so excited. i am a mere mortal myself and do not have the tools to properly measure the work performed by a shop i paid and trust to do it right the first time. i will be sharing this thread with my new builder fo sho.

i did know about the ABAB piston bore deal but did not know what the number stamp represented...

still dont know the reason why subaru doesnt just do AAAA OR BBBB all the time. although i have seen some cut like that...
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Old 09-25-2011, 03:55 PM   #18
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Quote:
Originally Posted by maxpowr
this is why this thread has me so excited. i am a mere mortal myself and do not have the tools to properly measure the work performed by a shop i paid and trust to do it right the first time. i will be sharing this thread with my new builder fo sho.

i did know about the ABAB piston bore deal but did not know what the number stamp represented...

still dont know the reason why subaru doesnt just do AAAA OR BBBB all the time. although i have seen some cut like that...
Its to make our lives complicated ;-). J/k I kinda am curious as to why as well. Anyone know?
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Old 09-25-2011, 04:01 PM   #19
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You might change that arp head stud torque from 80 to the current 90 ft lbs with moly.
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Old 09-25-2011, 04:04 PM   #20
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i assume it saves money for subaru somehow...
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Old 09-25-2011, 04:13 PM   #21
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I know Maxwell Power has been using a lot of ARP case bolts on builds and would like to hear what they have found. They were talking about it last time I was there, but I can't remeber exactly what was said .

This is the kind of threads I love in this forum. There hasn't been any good reading on here for a while.

OP, Could you post the part numbers of your bore gauge and mic set, and what they cost roughly? I have been wanting to start learning and put together my own motor for a while, so these tools have been on my wish list for a while.
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Old 09-25-2011, 04:15 PM   #22
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Quote:
Originally Posted by ASF Machine View Post
You might change that arp head stud torque from 80 to the current 90 ft lbs with moly.
Called ARP directly on Friday to confirm a couple of things:

(1) I wanted to know the torque value using the supplied lube
(2) I wanted to confirm that no deviation from the FSM torque sequence was required.

The tech told me 80 ft/lbs in 3 equal steps.
He also told me to use the FSM sequence as published.
I outlined the steps in the FSM to him on the phone and he confirmed that was the way they needed to be done.

Why do you suggest increasing the torque to 90 ft/lbs ?

Quote:
Originally Posted by morrocco88 View Post
I know Maxwell Power has been using a lot of ARP case bolts on builds and would like to hear what they have found. They were talking about it last time I was there, but I can't remeber exactly what was said .

This is the kind of threads I love in this forum. There hasn't been any good reading on here for a while.

OP, Could you post the part numbers of your bore gauge and mic set, and what they cost roughly? I have been wanting to start learning and put together my own motor for a while, so these tools have been on my wish list for a while.
I spoke to Dom twice on teh phone before i decided to buy the case bolts.
In his defense, he is not that willing to share specifics because he is in business to sell engines HE builds. I respect that.

However, he did tell me to install the bolts, torque the 10mm bolts to 60 ft/lbs and the 8mm bolts to 22 ft/lbs.

As soon as I get back from OfficeMax buying the wife a new office chair, I am going to re-install the case bolts and torque them to 60 ft/lbs and see where I end up.

I do not have high hopes that reducing the torque by 10 ft/lbs is going to significantly change the distortion, but I am willing to try for the good of the community.

Plus it has been a little cold in the garage this morning and now it has been 70*f for a couple of hours so I think everything should be up to temp for an accurate measurement.

Last edited by Team Scream; 09-25-2011 at 04:22 PM.
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Old 09-25-2011, 05:57 PM   #23
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Lots and lots of good info, thanks scream!
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Old 09-25-2011, 05:59 PM   #24
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subscribed!
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Old 09-25-2011, 08:26 PM   #25
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first post updated with 60 ft/lbs torque test
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