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Green 97 OBS
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Discussion Starter · #1 ·
Ok after tearing into a built EJ22t shortblock assembled by an amateur, I found that the crank is grooved with brand new standard clearanced ACL bearings. Crank is now at the machine shop for assessment on whether it needs to be cut or can survive with a polish. Assuming the crank is out of spec (99% sure it will need new bearings), what are my options?

Here's the basic setup:

EJ22t shortblock with squirters
12mm oil pump
EJ25D crank with #3 thrust and 48mm rod journals
Outfront H-beam rods and Wiseco stroker pistons (+.020")
EJ251 Heads with delta 1500s
Killer B pickup, STI pan and STI windage tray

Car will be primarily DD with expected output of about 400 WHP. Rev limit of 7k. I need to keep longevity, which is why I upped the oil pump. Overkill? Probably. I'm looking to add a custom oil cooler (with t-stat) if temps go too high. What I need to know is what brand would work for me and what clearances I should run.

Note- Engine will be warmed up as much as possible (maybe have a block heater installed) before driving much, let alone hard.


Brands- I have read the reports of ACL having terrible tolerances as of late. So if I have to run new bearings, should I avoid them? I have called king bearings, they do NOT have bearings for me. They only have OEM replacement for the #3 thrust mains, and the 48mm rods don't yet exist. They assure me they are still in development, but that doesn't help me right now. How are clevites? Any brand I'm missing that will hold up for what I'm looking at?

Tolerances- I'm aware of the general rule of 1 thousandth oil clearance per inch diameter. However I want to keep a happy medium between load capacity and wear minimization, leaning toward the latter. I was thinking of 0.0015 would be a good medium. It's on the loose end of factory but isn't to the point that would wear much more. Since I'm not going to rev things out, is that a good number? Go a bit looser? Tighter?
 

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Green 97 OBS
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Discussion Starter · #5 ·
7000rpm at the most, 400whp. No tracking is planned, just a street setup.

Rods are outfront h-beams with 3/8" ARP 2000s, they should be fine at the levels I'm talking.

Think rod clearance should be any looser than mains?
 

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yep. you heard me.
‘18 E63s AMG wagon & 10 Subarus
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Discussion Starter · #7 · (Edited)
I know, I've been a big fan of ACL until I heard they had bearings that came with differences in over .001 between each other. I thought about getting a coated set so they could be honed to the proper spec if they were out.

Just seeing what everyone else is saying before i decided to get another set.
 

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opendeck251+stiInternals
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Oem bearings never crossed your mind? A bit more than ACL's, has anyone done a comparo between acl and oem?

<----off to search....


~Josh~
 

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needs more cowbell
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I have standard acl in my ej20k. I installed acl "race" in the ej257 shortblock. I measured them to have bad clearance initially but then took the case to a machine shop (shop 2) to find the shop (shop 1) that honed the cylinders damaged (and filed/sanded down) the oem alignment dowels and it was allowing the case halves to slightly offset (something everyone who works on an ej should be aware of) and put the crank/bearings in a bind. After making some new dowels and getting new acls it rechecked good. Now the sb is done.
 

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With a 12mm oil pump I'd suggest ACL hx's. Find out how much is being taken off your crank and buy accordingly.

If you were going to use a 10 or 11mm pump, I'd suggest OEM bearings or OEM clearanced ACL's.

Cosworth is another brand but I wouldn't bother unless you're building for BIG HP, which it sounds like you're not.
 

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Discussion Starter · #15 ·
Thanks for the replies. Most of the responses I got on NASIOC was ditch the 48mm crank setup. No, I'm not going to do that since all these parts are new and there is nothing wrong with the setup other than the crank needs to be resurfaced. Period.

The reason I've started this thread is because the machine shop was going to set EXACTLY the tolerances I wanted and I did not know what would be best with the setup I wanted. Obviously I've got the oil pump to carry the extra clearance but I don't want excess wear. I probably will run minimum 10w40 oil maybe 20W50.

Well then I'll have a set of ACLs lined up, you guys are thinking leaving the tolerances a little looser? like .0017? The full .002?
 

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Discussion Starter · #16 ·
Bump for factory clearances.

Factory specs for my EJ221:

Mains #1, #5: .0001" - .0012"
Mains #2, #3, #4: .0004" - .0013"
Rods: .0004" -.0018"

Mains are at 60mm journals which is 2.36"-which would be .0024" oil clearance under the rule of thumb
Rods are 48mm journals which is 1.89" - which would be .0019" oil clearance under the rule of thumb

I'm thinking of putting the mains at .0015 and the rods at .0020. These aren't too far from what the engine builder's rule of thumb, though I'd keep the mains a little tighter. For nothing else, it's to make sure volume is kept to the rods, which should run a little looser for greater load capacity.

Or should I stay within factory?
 

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Discussion Starter · #19 · (Edited)
Good to know, impressive that you scored a basically running engine for that cheap.

There are at least 20-30 visible streaks on each main journal and countless more can be felt. So its gonna be a major polish at minimum. I did not mic the journals though. I should be getting a call from the machinist this week and he'll get me a better idea of what the damage is. Bright side is it doesn't look like my other crank :lol:

(I would do all this measuring here but I don't have a stretch gauge to reassemble the rods nor do I have a way to do a major polish)
 

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Discussion Starter · #20 ·
Machinist finally got back to me and the crank is only going to need polished. Because I'm running more clearance than factory he can get the crappy surface fixed with just the polish and I'll be good to go with the bearings I have, provided they're in spec when they are bolted in the journals. The mains I've already checked with the bore gauge and the rods will be checked before they're assembled for the final time after the polish.
 
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