In the process of having my motor built but there is not alot of local knowledge here about the VQ's so I need to tell the engine builder as much info as I can.

I was wondering which ACL bearing is recomended for FI and typical clearances that are run.

http://www.aclperformance.com.au/Nis...DEBearings.htm

I'm a bit confused as part number #6B2640H shows 3 sizes STD, 0.25, 0.025 so does this come in 3 sizes? Then I would assume there should be 3 part numbers but the web site lists only 1.

Also any recomendations on using standard oil clearance or the + 0.001" Extra oil clearance bearings? if so why?

Michael

 

I'm in the same boat as you and have decided to just hold off and let the machine shop order the bearings once the gap (Clearance?) size is known.

 

That is the proper way to do it.

Yes there are different sizes due to diffrent machining tolerances, and engine use.

I'd assume, tighter gap would mean higher oil pressures.

tom

 

Well, you cant just pick a bearing. You have to measure the journals on your crank and see if they are still within factory specs as per the FSM. Is it a brand new crank? Depending on how your measurements are will depend on how much thicker you need them to be. I went with the Standard size ACL because my crank journals both main and rod were all within spec. my part numbers were (6B2640H, and 4M2633H)

 

sorry to high jack your thread but i thought id just let people know the ACL has been having some finacial troubles lately, they were placed into administration and now i think are being liquidated. They are currently still manufacturing though which is good news.
ACL is only a small company of about 180 located In Tasmania Australia.

So please people buy their bearings

Back on topic, yes what streetzlegend said you wont know what to get till the motor is pulled apart.

 

I understand that the journals need to linished to match the size requirement. But what i didn't understand as per my first post was that part number 6B2640H is listed in 3 sizes. Is this true or am I miss understanding the info on the website. Basically when I order I would say #6B2640H please in size 0.025 etc

It is a used crank since out of a used motor that I'm building so I should be able to measure them now to find out which would suit.

Also just a general consensus for the + 0.001" Extra oil clearance option

Michael

 

I think you are misinterpreting the website, there are two size's on there. the 6B2640H, and the 6B2640HX. The same goes for the main bearings 4M2633H vs. 4M2633HX. Out of the two options the ones ending with X are the + 0.001". The ones without the X are the standard size.

 

Yep thats right, normaly the bigger sizes are for when you grind the crankshaft

Going with the extra thou of oil clearance will mean more oil to cool the bearing and more of a buffer between the two surfaces, this will also casue lower oil pressure and would normally be backed up by a high performance oil pump.

I'm no expert with only a couple of engines (old fords) experience so please someone correct me if im not explaining this right

 

Actually the H and HX are same size. Just the HX have a bit larger bore for the oil passages. It allows for a bit more oil to reach the bearings. You always order standard sizes (H or HX) for a straight rebuild. and measure it out. I usually coat the ones that have a bit too much clearance to bring them all into perfect spec. Usually just the mains. The rods almost always turn out perfect with just a set of standards.