OEM vs ACL bearings


Any idea on the prices we are looking at?
Bearing(that pun again!) in mind there's a few of us needed these pretty much now lol
 
You guys know its the oil film that is in contact with the crank right?
The white metal is sacrificial to get the right clerance.

Ive spun two big ends and wrecked two engines. It was naff all to do with the bearing.

If they gave a clearance in tolerance I would happily have ACL ones.
 
This what some of us have been saying. It's all personal preference end of the day, I personally won't spend £400 on bearings.
 
JohnTurbo said:
You guys know its the oil film that is in contact with the crank right?
The white metal is sacrificial to get the right clerance.

Ive spun two big ends and wrecked two engines. It was naff all to do with the bearing.

If they gave a clearance in tolerance I would happily have ACL ones.
Click to expand...


Exactly.

As I mentioned that when a friends engine/oil pressure failed the ACL Bearings were scored but the crank was like new which wasn't a bad thing as the bearings were sacrificial

I would still think that there would be some sort of (lubricated) contact between the bearings and the crank on startup just before the oil pressure is high enough for the crank to wet float but what sort of difference different bearings would make here Im not sure
 
I would go for the ACL bearings a mate has them in his b18 turbo build with no problems, I think most engine builders recommend .002 thou clearance anyway.
 
Can't believe I missed this thread. OEM purely due to the variation of sizes to allow for precise tolerances and are not as harsh on the crank due to been softer.

My big end bearings were 3x brown and one black dispute the crank measuring spot on and markings calling for all green so please
make sure you check this out before going on what the machine shop says Nicole, just for peace of mind. I've ordered 3 batches of plati gauge for £11 to double tripple check my bottom end lol
 
Also in on a price for Oem bearings. Was going to message you Eternal.
 
His pricing on dura glide ACLs are very good.
All oem runs in very expensive, I know cost shouldn't come into an engine build but unfortunately it does lol
I'm going for the ACL dura glides from eternal and will check my clearances to be sure I'm happy with them. Checking using a dial bore gauge and a micrometer, then double check again with plasti-gauge, although plastic gauge isn't going to be as accurate as the bore gauge it will put it in the ball park and will help me double check I'm doing everything properly lol
 
Stick a stock b18c4 in there lol your power goals will be light work in a good one. :)
 
Too late now bud lol got 1k worth of parts sitting in the loft.
Also won't go with a c4 as I've explained before. If this build goes tits up then I may have to do that.
But it won't lol
 
could of done it other way round though and built the forge engine on the side while you put the c4 through its paces
 
Yeah could have done, doesn't matter if the cars off road though. Would also mean tuning it twice and buying another engine etc.
Shouldn't be long till the engine built anyway, well before Xmas lol
 
Back on topic, stumbled across some info whilst I was revising my own build that I think could be useful to this thread.
The OEM bearings max tolerance change between the whole colour chart is about 0.0008". That's 4 decimal places. Pretty small change IMO
The ACL race bearings come with an EXTRA 0.001" (3 decimal places) clearance over "standard size" built into them for whatever reason.
The ACL dura glides don't have the extra clearance that the RACE versions do but they are made of a softer material that cannot support as much load, whether our engines are anywhere near reaching that load is anyone's guess, one for @Kozy I suppose?
Anyway I'm less worried about that than I am the clearance.

Now for the RACE ACLs to have been successful in so many builds previous tells me that searching for the 4th decimal place on the clearance isn't CRITICAL to the engines longevity. As they are already 0.001" oversize and this is already over the max differential the OEM colour system gives at 0.0008" so going from a green bearing to a race ACL would yield a clearance over 0.0006" over the max OEM tolerance.
Some builds must have exceeded this clearance? Only good thing about the RACE bearings is you'll never be too tight? Taking price out of the equation obviously.
 
Anyone have anything to add to this? Worth making this the go to place when arguing about bearings lol
 
it appears the ACL race bearings come in two sizes for standard cranks, the size based on the oem greens and the oversize your talking about

The guff from the listing on inline four :

ACL's are made with the same manufacturing process as Honda, they just don't come in the .0001 adjustments by colors. They match the green color code in most instances. They are a one size fits all that on a STD size crankshaft within spec, will give you clearances right in the middle of the spectrum of which Honda specifies.



Also, ACL offers a bearing size that is .0005 thinner per half, allowing for .001 extra clearance for STD sized crankshafts. For street applications, we highly reccommend the STD size only. The .001 THINNER FOR STD SIZE CRANKS, should only be used in race/track applications or where you need to achieve more of a loose clearance.

Link to page
http://www.inlinefour.com/aclraenbe.html
 
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Ahh of course!
So would seem ACL recommend a looser clearance on race/track engines.
Wonder if it's just rev related or if power plays a part in the clearance required aswell?
 
jesse888 said:
Ahh of course!
So would seem ACL recommend a looser clearance on race/track engines.
Wonder if it's just rev related or if power plays a part in the clearance required aswell?
Click to expand...

I'd say it's Also because of higher temps and faster /greater expansion of components in track use,
 
Yeah, power playing a part in that obviously. Another variable then lol
 
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