Rb26/30 Knock Sensors

[=premo=]

Just trying to find the easiest way around attaching them to the RB30 block.

Block is a 12mm hole, the knock sensors are a 8mm donut.

I was thinking of using a heli coil but I dont know how effective this would be.

Any ideas??

[Adriano]

There are no holes where the rb26 knock sensors are located. I just drilled and tapped the holes, and attached

[ahh 33 s2]

i thought there where holes for the knock sensors in the 30 block. or is that for using 25 sensors??

[Adriano]

I think thats for the 25 sensors, they are located lower in the block then the 26 ones from memory.

[VB-]

do the RB25/6 ones work on the same voltage scale as the RB30 one? might just be able to use a 30 item?

[Adriano]

Dont think so, they are a completely different design. Plus a 25/26 has two of them which would be more effective at picking up knock

[Cubes]

RB25 and 26 use a completely different scale.

[ahh 33 s2]

meaing you have to drill and tap holes for the 26 sensors in the 30 block

[Cubes]

That is correct.

[=premo=]

Ended up using a heli coil inside a heli coil to fill the 12mm RB30 hole down to a 8mm hole, it worked very well and I used a little lock tight to make sure the coils dont move.

[VB-]

i'd be careful with that as the helicoil's with loctite may act as a damper between the sensor and the block... anyone know for sure?

[=premo=]

The metal face on the underside of the knock sensor is clamped up against the flat surface on the block very tightly by the 8mm bolt so the heli coil shouldn't make a difference to the readings. If the bolt was part of the sensor like the RB20 and 25 knock sensors then the heli coil may make a difference as they rely on the thread to transfer the vibration instead of the surface.

[ahh 33 s2]

what is heli coil and is this the best way to make this modification

[GTR-Ben]

Washer + bolt. Worked fine for me..

[Cubes]

<scratches head>

What do you mean washer + bolt?

[GTR-Ben]

Well thats what I recall doing.. I used a bolt and a washer on each GTR knock sensor when I mounted them to the RB30 block.

Maybe I didn't use the original holes for the RB30 knock sensors but ones close. The knock sensor worked fine today on the dyno however.

[ahh 33 s2]

i dont quite understand that concept either. but still what is a heli coil??

[GTRsean]

Fitting a helicoil (screw thread insert) is a great way to repair damaged threads and restore the component so the original bolt size can be reused.

The secret to the helicoil is that, prior to installation, the insert is larger in diameter than the tapped hole. Before hole is tapped to suit the helicoil it is drilled a larger size.

[James_03]

you shouldn't need to drill and tap anything, there are holes in the rb30 block that suite. I just did what gtrben did worked fine.

[Cubes]

I know the area you are talking about but my holes are what looks like filled in with some sort of epoxy or hard crap.

You can just see where the paint is slightly smooth/shiny looking in the centre of the top lugs.