Ok, I know this topic has been discussed to death, but with 20+ years of forums I cant find any clear information, let alone up to date information. I need a few things explained, for context, I'm building a d16z6 for 250-300whp, I'm going with eagle rods and cp .0020" over 10.5:1 pistons. I bought an engine off fb marketplace for the build, and took the head, block, and crank to the machine shop. They bored the cylinders .0020" over, decked the block, cleaned it, resurfaced the head, did a valve job, replaced some valve guides and seals, cleaned it, and polished the crankshaft. I now need to know what bearings to buy. Heres the information I have that I need clarity on, from the factory, honda put different bearings in each section so that the clearances would be perfect on each. These are color coded. I've also heard you cant buy them anymore, is this true, and should I just not even be considering them? Assuming I shouldnt even be considering oem bearings, I see 3 real options, king, acl, and clevite. Between king and acl people tend to fight it seems as to which is better, and I havnt heard much about clevite. Heres where I'm confused. It does not seem like each brand has an equivalent sized bearing to the honda oems, they just have std size and an oversized? or maybe they have more options but I cant tell what they are? I also am pretty sure I dont want race, as this will be a street car and my goal is to not rebuild the engine for 100,000+ miles. Also real street performance (Where I'm building my rods, pistons, and bearings package) does not show king have non race main bearings. Am I just missing something? And I had my crank polished, does this mean I need oversized bearings? what about my cradle, do I need to do machine work to it? So I not only dont know what size bearings I should even want, I dont know what my options for bearings even are. And lets say that because I can no longer trust the oem size markings because I had my crank polished, How do I measure it? plastigauge requires that I already have the bearings so its a catch-22 thing. Also what clearnce should the plasticgauge read? Some people say .0015, some say less because looser is better? I'm super confused on the whole thing and could really use some advice, I dont just want to buy standard acls and throw them in just for the plastiguage to tell me I'm way off.

 

You are going to need rather expensive tools to get measurements of the crank journals, rods and mains. Reliable measurements to the 0.00001 of an inch are expensive. If you are aiming for clearance in the 0.0015 range that's the level of accuracy you need.

Orrrrrr take it back to the machine shop and pay them to document the sizes for you.

After you have measurements you can make educated purchasing decisions about your bearing sizes. Then you can install those bearings and crush them in their caps and then measure again to make sure the desired clearance is the actual clearance you have.

 

ok, but what do people normally do? I'm struggling to understand because its not buy the expensive tool, and I havnt seen anyone say that they payed a machine shop to measure. And did having my crank polished change the size or no? I know theoretically it would have had to, but does it change it to the point of needing different bearings? I'm also not confident saying that .0015 is what I want, I'm asking what I should be aiming for, what is normal

 

Most people are in one of two camps. Slap it together and hope it's good or pay a machine shop to put it together.

A happy medium here might be have the machine shop give you measurements and then order bearings and verifiy with plasti gauge.

 

The factory service manual shows a min/max range for oil clearances of the main and rod bearings. Obviously, the factory bearings have a special color code to allow one to alter (within some limitations) this oil clearance +/- one or two tenths at a time to your specific needs, whereas, any of the aftermarket brands that you mentioned above will be a single size, hopefully providing an oil clearance that falls within the min/max range of the factory specs. This is why I build with OE bearings... I just don't believe that the "One size fits all - go/no go mentality" is the answer.

As Ryanthegreat1 stated above... most people just slap the shortblock together and pray... or if they even bothered to measure or plastigauge, even if there was a journal that didn't fall within spec, they run it and don't bother with really solving the issue.

 

Do they still make the oe bearings? I thought they had stopped. and I'm just struggling a little because there are countless testimonials on this forum of people who have put together engines with acls or kings and had no problems. So i still have a few unanswered questions, and would polishing my crank change what bearings I would need, or can I go off what is stamped in the block and cradle?

 

Polishing removes material. Would need to measure to know how much material was removed and if you are still in spec for the stamped size.

I bought Honda bearings for my D16 build a few years back.

 

Only two main bearing shell colors currently show being discontinued... and all rod shells show available. The question is are they actually out there somewhere ? The thicker shells seem available, and since you have micro-polished your crankshaft, you will likely need thicker bearings... and they should be available.

 

I used ACL bearings on mine and just plasti-gauged to make sure I was in the range I wanted to be.

I agree with both gentlemen above. For peace of mind, pay the machine shop to measure and give you a report. Then you can do the math to calculate bearing sizes based on desired clearances.

Or...you can have the machine shop measure everything and then hone rod/main bores to size to achieve the clearances you want based on the standard off-the-shelf bearing size. With OEM bearings, this was less desirable as you can't go backwards and put material back on the rods/mains. But, as OEM bearing supplies dry up, this practice may become more commonplace.

 

Ok final question, What clearance should I be going for for rods and mains? like what should the plastigaugue come out to be?

 

honestly it depends and can vary based off your oil preference. Very general though, I would look for the upper limit of oem specs just shy of the service limit. Say .0018 +/- .0002 or so off the top of my head, but its been a while since I built a sohc...