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Old 03-27-2014, 10:33 PM   #226
Paul
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and the other alternative is a block guard/closed deck like outfront motorsports and a few others do.

Don't over think this man.. all you need is pistons and good rods....Hell JR went 10.0 @ 142mph with a stock sleeved piston/rod motor w/ a 6466
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Old 03-28-2014, 01:45 AM   #227
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Yeah true... I'm thinking about just going for the gt35r lmao
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Old 03-31-2014, 08:02 PM   #228
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Hey guys, so my Brian Crower H-Beam rods w/ ARP2000 bolts, as well as my 99.75mm CP Pistons came in the mail! I'm starting to review the notes on assembling the piston rings, and there doesn't seem to be a niche on one of the rings that goes around the expander.

Are there any good references out there for showing piston ring installs on a WRX / STi? Oh, and there aren't any dots on the rings, but the 2 thick rings have "n25" on one side.

Does the plated thick ring be the most upper ring, relative to the top of the piston ( valve relief side ), or is it the other iron looking one with no shine?

OH - and is the expander ring supposed to overlap itself, or should the tips between the gap touch?

Thanks guys!
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Old 04-01-2014, 12:30 AM   #229
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Any mark on a compression ring indicates the "up" side. Yes the plated ring is the top ring, non plated is 2nd. No, the expander never overlaps, the ends butt up. It will be obvious when you get to installing them. Top ring grooves should be 180 apart, expander gap is typically located over the pin end, 2 rail gaps one inch either side of expander gap. I don't know what you mean by no "niche" on one ring.
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Old 04-01-2014, 01:06 AM   #230
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Quote:
Originally Posted by Motion Machine View Post
Any mark on a compression ring indicates the "up" side. Yes the plated ring is the top ring, non plated is 2nd. No, the expander never overlaps, the ends butt up. It will be obvious when you get to installing them. Top ring grooves should be 180 apart, expander gap is typically located over the pin end, 2 rail gaps one inch either side of expander gap. I don't know what you mean by no "niche" on one ring.
I just played with the pistons for a couple of hours, putting them on and off, and reading documentation. Seems pretty straight forward! I just had to find videos on how to do it, looks like. *Pause video* .... "Yeah that ring is shiny, that's the one!" hahaha.
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Old 04-01-2014, 01:07 AM   #231
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Should I be able to install the piston rings before bringing them to the machine shop, or would that make it a PITA for them?
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Old 04-01-2014, 07:18 AM   #232
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Should I be able to install the piston rings before bringing them to the machine shop, or would that make it a PITA for them?
Put them on last, between you and the shop handling them, one might get damaged. Plus you'll want to check the ring gap after the machine shop is done with the block.
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Old 04-01-2014, 01:16 PM   #233
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Just dropped the pistons and case bolts off at the machine shop. They're going to diamond hone torque plate the cylinders for the .003" ptwc, and measure the main clearances for me.
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Old 04-01-2014, 01:17 PM   #234
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you drop your heads studs off also??
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Old 04-01-2014, 01:21 PM   #235
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you drop your heads studs off also??

Oh, yes. They've had my case halves and head studs for about a week now. They measured the bores for me, and I've delivered the pistons to them finally

Really hoping I don't need a line bore on this block ... lol - already looking at an unexpected expense of $600 for the heads
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Old 04-02-2014, 09:32 AM   #236
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Hey guys,

If i'm planning on running up to 30lbs of boost, should I leave the PTWC at the .003" that CP puts on their spec sheet?
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Old 04-03-2014, 03:45 PM   #237
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Hey guys,

If i'm planning on running up to 30lbs of boost, should I leave the PTWC at the .003" that CP puts on their spec sheet?
.003" it is...

The King rod bearings (Standard size) came in the mail today! I'm going to measure each of them this weekend to make sure they're all in spec.

Hoping to get the block back from the machine shop tomorrow~
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Old 04-03-2014, 05:15 PM   #238
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Quote:
Originally Posted by BeastianSTI View Post
Hey guys, If i'm planning on running up to 30lbs of boost, should I leave the PTWC at the .003" that CP puts on their spec sheet?
You should contact CP on this. Typically 2618 alloy has PTW of 0.0035". To loose you promote ring wear and little noise. To tight you risk have piston swell and seize in the bore.
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Old 04-04-2014, 09:04 AM   #239
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Yar, the spec sheet said .003" pretty much. There were no provided ranges as part of the instructions :S
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Old 04-04-2014, 09:50 AM   #240
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Quote:
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You should contact CP on this. Typically 2618 alloy has PTW of 0.0035". To loose you promote ring wear and little noise. To tight you risk have piston swell and seize in the bore.
Although engine builders have ran them at 0.0025" and haven't seen scuffing. It all depends on how much power you want to push. 400whp and 0.0025 would more than likely be fine and the engine would last a good amount of time. 700whp it would seize in the bore due to more heat at that ptw.
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Old 04-04-2014, 10:08 AM   #241
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Although engine builders have ran them at 0.0025" and haven't seen scuffing. It all depends on how much power you want to push. 400whp and 0.0025 would more than likely be fine and the engine would last a good amount of time. 700whp it would seize in the bore due to more heat at that ptw.

.003" at around 400-450 WHP probably, MAX. I agree though
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Old 04-04-2014, 10:48 AM   #242
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Quote:
Originally Posted by Delphi View Post
Although engine builders have ran them at 0.0025" and haven't seen scuffing. It all depends on how much power you want to push. 400whp and 0.0025 would more than likely be fine and the engine would last a good amount of time. 700whp it would seize in the bore due to more heat at that ptw.
Not sure if you miss read my post as I stated 0.0035" not the 0.0025" you speak of.

Me personally run it more in the looser side as it will last just as long and you run less risk of piston seizing. Also same goes for the ring gap. If you are playing with built motors and high boost you should expect to rebuild motor more often. Built motor isn't going to be same life as oem motor.
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Old 04-04-2014, 12:05 PM   #243
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Looks like the block is about ready to be picked up. Good news!! They said there weren't any issues with the main being out of round, etc!

I'll be receiving a granular list of the measurements that i'll post here once the time comes.

Hoping to be able to buy standard sized main bearings. Not sure if I should go with the King XPG Main bearings, Cosworth, or OEM. Anyone have input/experiences with these?
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Old 04-04-2014, 05:34 PM   #244
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SWEET! Got the short block back from the machine shop.

No decking was needed - surface was perfectly level.

No line bore needed - all main surfaces were right in spec; i'm going to pick up some STD main bearings


The shop is going to polish up my crank and do the heads for 400!
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Old 04-05-2014, 10:27 PM   #245
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After doing some reading, I'm considering if I should meticulously measure the rods bearing clearances or not. I've hear that it's better to run looser clearances than tighter, but I think since the crank is in good shape and will be polished, I can get away with all standard king bearings. What do you guys think ?
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Old 04-06-2014, 08:47 PM   #246
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Bumpppp
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Old 04-06-2014, 09:10 PM   #247
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Originally Posted by BeastianSTI View Post
After doing some reading, I'm considering if I should meticulously measure the rods bearing clearances or not. I've hear that it's better to run looser clearances than tighter, but I think since the crank is in good shape and will be polished, I can get away with all standard king bearings. What do you guys think ?
You can easily research this question on here as its been answer probably a thousand times, some reason people like to be spoon feed on here instead of looking for their answer (sorry not trying to sound like ass, but reality is reality). Yes you want to measure the bearings with real measuring tools, please don't use plastigage as its no where near as accurate as mic/bore gauge will be. For clearance you want to run around 0.0015"mains and 0.002" on rods. You can go slightly loose on these but not by much. I won't recommend polishing the crank as it removes the harding on it, if its needed don't skimp on it and just replace it as its roughly $320 for new one. Its rather pocket changed compared to the work you will have to do if it isn't done correctly. Also for bearing size, pick what you like and go with it, if it ain't right then buy another set whether it be same size or difference in direction you need to go. Its trial and error, nobody is going to be able to tell you exactly what you will need. I tried set of kings, I believe they was +1 IIRC, Im to lazy to go find them to look. They turned out to loose, I had set of OEM bearings and tried them, guess what they were almost exactly what I needed so I went with them (0.0017 mains and 0.0019" rods IIRC). The king bearings was consistent, but I personally like the OEM bearings as generally you don't see any problems with them, it seems ACLs are crap shoot. This was on stock style rebuild with stock rods and 4032 upgraded pistons. I perfer stock rods over the cheaper H-beam crap thats out there is reason for stock rods, next build will be Carrillo or something similar. If you have aftermarket rods, that will play into the equation and your results may vary from others.
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Old 04-08-2014, 10:46 AM   #248
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Ok - thanks..

Machine shop just called and let me know that two of the intake valves were out of spec, and ALL of the valve guides were well past spec. No wonder they sounded louder than most lol.
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Old 04-08-2014, 11:57 AM   #249
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Beastian,

I agree with bswilmington on not polishing the crank. As for the bearings just order both king std and +0.0001. It honestly isn't much more. That way you should be able to hit the clearances you want to hit.

If you haven't read this thread I suggest doing so.
http://forums.nasioc.com/forums/show....php?t=2265011
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Old 04-08-2014, 12:39 PM   #250
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Hmm ... i'm kind of torn because the machine shop saw the crank and said it definitely could use a polishing. You could feel tiny bumps / unevenness in a few of the surfaces. Should I call polishing the crank off and buy a brand new crank?
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