S15 SR20 rod bearing width - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

tb13 · 04-22-2017, 11:28 PM

So I have an S15 SR20 I recently picked up to rebuild, doing some research I have come across some people saying these motors use the standard 17mm bearing and others saying they use a 19mm bearing. So I grabbed a rod cap and measured the bearing.

Looks to be 19mm from what I can see, am I measuring it correctly? If I reuse these rods I want to make sure I am buying the correct size bearing, can anyone confirm I am measuring this correctly or maybe post up a picture you measuring an S13 SR20DET bearing?

tb13 · 04-23-2017, 01:54 PM

Answered my own question last night, did a bunch of digging around and used my FAST program to confirm my suspicions. Figured I'd share what I found so the info was out there for anyone who might get a motor like mine or purchase a set of specific OEM rods.

The S15 SR20DET I have does in fact have 19mm rod bearings. This confirms that there are some DET motors, other than the GTi-R, that use a 19mm bearing vs the standard 17mm. Although my motor does use 19mm bearings, I don't believe all S15 SR's are created equal due to the fact that FAST lists only the standard 17mm rod and bearing part numbers.

Now after looking at my rods again I noticed an "8H6" casting on each, for those who know about the SR20VE, you know that "8H6" stamped heads are the best flowing heads used in the P12 Primera and T30 Xtrail. Using fast again I checked out what part number the T30 Xtrail lists for its rods.

As you can see the part number for the rods and bearings ends in an 8H600, meaning that these are specific and different bearings from the rest of the SR20 family of motors. This is very similar to how the GTi-R rod part number is different from the rest of the SR20 family due to its larger bearing.

In conclusion, if you end up with 8H6 rods you cannot run the standard 17mm rod bearings. I have no doubt that running a 17mm bearing in these rods would end in spun bearings and headaches. I hope this info can be helpful to someone in the future.

I also found a thread over on SR20-Forum where someone measured a set of GTi-R rods and bearings showing the difference between the 17mm bearing and 19mm bearing. Looks like the only difference is the size of the alignment tab on the bearing and cut out on the rod. If you want to check it out, Click Here

joaquin714 · 04-13-2019, 10:32 PM

Good info thanks was about to order the s13 bearings for my s15 block, could have been catastrophic

04-22-2017, 11:28 PM	#1
tb13 Zilvia Addict Join Date: Feb 2014 Location: Arizona ٩( ᐛ )و Subaru Parts Consultant Age: 29 Posts: 848 Trader Rating: (3) Feedback Score: 3 reviews	S15 SR20 rod bearing width So I have an S15 SR20 I recently picked up to rebuild, doing some research I have come across some people saying these motors use the standard 17mm bearing and others saying they use a 19mm bearing. So I grabbed a rod cap and measured the bearing. Looks to be 19mm from what I can see, am I measuring it correctly? If I reuse these rods I want to make sure I am buying the correct size bearing, can anyone confirm I am measuring this correctly or maybe post up a picture you measuring an S13 SR20DET bearing?

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04-23-2017, 01:54 PM	#2
tb13 Zilvia Addict Join Date: Feb 2014 Location: Arizona ٩( ᐛ )و Subaru Parts Consultant Age: 29 Posts: 848 Trader Rating: (3) Feedback Score: 3 reviews	Answered my own question last night, did a bunch of digging around and used my FAST program to confirm my suspicions. Figured I'd share what I found so the info was out there for anyone who might get a motor like mine or purchase a set of specific OEM rods. The S15 SR20DET I have does in fact have 19mm rod bearings. This confirms that there are some DET motors, other than the GTi-R, that use a 19mm bearing vs the standard 17mm. Although my motor does use 19mm bearings, I don't believe all S15 SR's are created equal due to the fact that FAST lists only the standard 17mm rod and bearing part numbers. Now after looking at my rods again I noticed an "8H6" casting on each, for those who know about the SR20VE, you know that "8H6" stamped heads are the best flowing heads used in the P12 Primera and T30 Xtrail. Using fast again I checked out what part number the T30 Xtrail lists for its rods. As you can see the part number for the rods and bearings ends in an 8H600, meaning that these are specific and different bearings from the rest of the SR20 family of motors. This is very similar to how the GTi-R rod part number is different from the rest of the SR20 family due to its larger bearing. In conclusion, if you end up with 8H6 rods you cannot run the standard 17mm rod bearings. I have no doubt that running a 17mm bearing in these rods would end in spun bearings and headaches. I hope this info can be helpful to someone in the future. I also found a thread over on SR20-Forum where someone measured a set of GTi-R rods and bearings showing the difference between the 17mm bearing and 19mm bearing. Looks like the only difference is the size of the alignment tab on the bearing and cut out on the rod. If you want to check it out, Click Here

04-13-2019, 10:32 PM	#3
joaquin714 Zilvia Member Join Date: Jul 2007 Location: California Posts: 192 Trader Rating: (1) Feedback Score: 1 reviews	Good info thanks was about to order the s13 bearings for my s15 block, could have been catastrophic