Rb30 Bearings In Rb26

[Mik]

I have heard of a lot of people using RB30 main bearings in RB26 engines.

I know you have to drill 5 holes in each upper shell, but also the RB30 bearings are 19mm wide and the RB26 are 20mm.

Does this cause any issues?

[Duncan]

I was going to say this causes no issues but then again I spun an rb30 bearing in my 2000klm old rb26. On the other hand exactly the same bearings in the other race car are going strong after 2 seasons including 2 targas.

[Mik]

I was going to say this causes no issues but then again I spun an rb30 bearing in my 2000klm old rb26.  On the other hand exactly the same bearings in the other race car are going strong after 2 seasons including 2 targas.

<{POST_SNAPBACK}>

Did you spin a big end or a main?

What sort of bearings were they?

The reason I ask is that I have a set of ACL race bearings supposedly for an RB26, but the main shells are only 19mm.

[Duncan]

not sure yet I am just guessing, it is still in the car. I also used the ACL race series ones

[WetGTR]

I was going to say this causes no issues but then again I spun an rb30 bearing in my 2000klm old rb26.  On the other hand exactly the same bearings in the other race car are going strong after 2 seasons including 2 targas.

<{POST_SNAPBACK}>

I think there is some machining requirments for them to fit but proper installation is required. It might not be the bearings fault, other factors could of caused the spun bearing issue.

[R32-GTS]

I would use the 20mm bearings designed for 26 heard a few stories of the vl bearings in 26's shitting themselves ,

[StockyMcStock]

why would you use RB30 bearings in place of proper 26 shells? surely the cost difference couldn't be the reason due to the extra machining needed to make them fit?

[WetGTR]

why would you use RB30 bearings in place of proper 26 shells? surely the cost difference couldn't be the reason due to the extra machining needed to make them fit?

<{POST_SNAPBACK}>

It's got to do with what products are available. The bearings available for the RB30 are vast where the RB26 has a smaller range. Also the type of bearings are limited for the RB26.

For example: You might be able to get a higher grade bearing, a certain brand of bearing but only for the RB30. They just require a bit of machining and don't look as pretty as the ones made for the RB26. Who cares about the looks of it as long as it does the job but it would concern me that the right machining is done.

If its wrong then SPUN BEARING. I think this is one of those reasons to try and stick with ones made for the RB26. If your engine builder is confident about the machining process and you don't car how they look then RB30 ones are the way to go if they have what you are looking for.

Hope that made sense....

[StockyMcStock]

not really. surely there'd be a few top-of-the-line bearings for the 26? you only need one company to make good ones and they're the ones you'd buy.

for instance, i got genuine nissan mains for my RB30 but i almost went King bearings or Clevite. with the 26 you can choose genuine nissan first off again, as i would.

but it may be a more common process than i think i guess, i just assumed all the drag RB26's used nismo or tomei (for example) bearings for the higher RPM experienced by the 26.

very interesting subject though.

[Beer Baron]

it is an interesting topic. I've come across this problem with GTI-R SR20s. they use 19mm rod bearings where as regular (rwd) SR20s use 17mm conrod bearings. for a long time it was quite common to use the smaller bearing, but the consensus is that it's far better idea to use the right size bearing.

[WetGTR]

As you can see there are limited companies that produce the bearings for the RB26 re: Nismo, nissan, tomei.

The problem is when a company like ACL or King has bearings that you wish to use on the RB26 but haven't yet released them for it but have released it for the RB30 or they just don't have the right size your after for the RB26.

I'm not saying this is always the case but I know engine builders can use the bearing from an RB30 when they are required to do so.

Hopefully these companies catch up and produce the all available range of bearing for the RB26.

Kings have bearings for the RB26 which I beleive are superior to the Nismo, Nissan ones re: Nissan, Nismo are tri-metal and Kings are bi-metal

Edited October 24, 2005 by WetGTR

[blk180]

Yep i used kings bearings in my 26 all happy days so far with about 5000kms on the motor

[Duncan]

Also, don't forget that the local bearings are less than a 1/3 of the cost of nissan ones.

obviously that counts for nothing if you spin one and have to pull the motor, but if it is OK you save a heap on the rebuild

[Mik]

As you can see there are limited companies that produce the bearings for the RB26 re: Nismo, nissan, tomei.

The problem is when a company like ACL or King has bearings that you wish to use on the RB26 but haven't yet released them for it but have released it for the RB30 or they just don't have the right size your after for the RB26.

I'm not saying this is always the case but I know engine builders can use the bearing from an RB30 when they are required to do so.

Hopefully these companies catch up and produce the all available range of bearing for the RB26.

Kings have bearings for the RB26 which I beleive are superior to the Nismo, Nissan ones re: Nissan, Nismo are tri-metal and Kings are bi-metal

<{POST_SNAPBACK}>

King do not make bearings for the RB26. They do make for the RB30, but these are a 19mm main and you need to drill holes in the upper shells.

ACL do make RB26 bearings, but they have made a mistake, and made them 19mm instead of 20mm (they copied the wrong sample).

Nismo offer mains (they are the same NDC brand as OEM ones). and are supposedly a bit better.

Tomei and NISMO offer big ends, never seen a Tomei bearing though.

Also, the N1 models use the same mains as the normal GTR's (nopt sure about big ends though)

[blk180]

im sure when my engine was built we used Kings bearings that were for rb26 because i said use ACL and he said kings bearing where better but i will have to ask them in two weeks when go in for anther oil change. i also found that every part i brought for my built was machined at the machine shop in some way ie, PAR rods were not perfect, Mahl pistons had a 21.1mm pins and the crank was grub screwed and everythink was balance

[blk180]

MIK appears you are right just checked there site and no RB26 bearings yet o well grrrrrrrr im sure they said they for rb26

Edited October 25, 2005 by blk180

[Mik]

MIK appears you are right just checked there site and no RB26 bearings yet o well grrrrrrrr im sure they said they for rb26

<{POST_SNAPBACK}>

Yours would be King RB30 bearings which alot of poeple have used in RB26s (you need to drill holes in them though).

[ACL]

I have heard of a lot of people using RB30 main bearings in RB26 engines.

I know you have to drill 5 holes in each upper shell, but also the RB30 bearings are 19mm wide and the RB26 are 20mm.

Does this cause any issues?

<{POST_SNAPBACK}>

ACL Bearing Company is aware of the RB30 main bearings 7M2394H being used in RB26 prior to the RB26 mains 7M2428H being introduced and we believe these have functioned quite satisfactorily, however

the differences between the two sets are:

1) the RB26 upper mains have 5 oil holes and the RB30 has only 1 (engine builders were drilling the additional holes)

2) the RB26 plain mains are 20 mm wide vs 19mm for RB30- The 19mm wide bearings have been functioning quite satisfactorily as the ACL 7M2428H was introduced with 19 mm wide mains, however since having a number of requests for the 20 mm wide bearings, we will be making a running change to the 7M2428H set, which should be available approx late December 05. (the additional 1mm is an equal 0.5mm per side)

3) the Flanged main for the RB26 is .002" (0.050 mm) wider than the RB30 main, so endfloat will be slightly different if RB30 mains were used (this may still be within acceptable limits)

The ACL RACE bearings premiumTrimetal bearingsand are specifically designed for high performance engines. The material used is a high strength copper lead material bonded to a steel backing, with an improved strength overlay, for added fatigue strength. Con rod bearings have a hardened steel backing material which helps maintain their crush under higher load and temperature conditions during operation.

Design features-

Bearing eccentricity- (i.e the reduction in wall thickness from the thickest section at the crown of the bearing to the point 10mm from the parting line) is increased to compensate for bore distortion which will occurr due to higher inertia loads, and to assist with formation of the oil wedge to build thevital hyrdrodynamic oil film which seperates the shaft and bearing, to prevent wear. This also helps to maintain a good oil flow through the bearings, essential for heat dissipation away from the bearings.

Crush-is the amount the shells are circumferentially longer than the true half diameter of the housing bore. Crush is increased on these bearings for improved bearing retention and heat disipation.

Wall size tolerance is +/- 0.004 mm (+/- 0.00015") for consistent vertical oil clearances.

The trimetal bearing is a high load carring bearing, with good surface properties(i.e seizure resistance, dirt embedability, conformability) with enhanced chemistry of the overlay plated surface layer for improved fatigue resistance. Fatigue resistance is also improved on the con rod bearings by reducing the overlay thickness to 0.013mm (0.0005"), and there is no flash plating on the bearing backs, so there is no "migration" of plate on the bearing backs under heavy loading, improving thermal transfer and seating of the bearings in their housings.

These bearings are available in 7M2428H -STD/0.025 / 0.25/0.50

7M 2428HX-STD (this gives 0.025 mm(0.001") extra clearance over the 7M2428H-STD)

6B2960H-STD/0.025/0.25

6B2960HX-STD

RB 25 uses the same main bearings as the RB30 7M2394H/HX

Same con rod bearings as the RB26 6B2960H/HX

It is acceptable to use bearings of adjacent size together on the one journal to get the required vertical oil clearances eg a .025 shell with a STD shell

Product Engineering ACL Bearing Company

[Sydneykid]

Holy crappola, you know you have a relevant web site when an large company like ACL posts information on their products directly.

cheers

[Beer Baron]

Yes John from ACL, thanks for posting that up. Very relevant info. Good to see people who are willing to help get the real information out there for us customers to use.