Knock Sensors

[wig r31]

Just wondering what other people have done about the knock sensors? As Im Running a standard ecu for now. I have a series 2 rb25 head on the rb30e block

any thanks would be greatly appreciated

[Bliksem]

easy, take the rb25 knock sensors and screw them into the provisions on the rb30 block

Edited June 11, 2009 by MintR33

[wig r31]

easy, take the rb25 knock sensors and screw them into the provisions on the rb30 block

Im pretty sure there weren't any spots for them on the 30 block. Just trying to find out if there is another way around it without tapping 2 new threads in the side of my block (I dont get the car back till saturday so I'll check the block again then. Thanks for the idea tho )

[Bliksem]

My personal experience as with many others was that the knock sensors were a straight swap. As far as I know both S1 and S2 RB30 blocks have the same provisions for knock sensors as RB20, 25 and 26. If for some reason yours is does not have these you may have to do something custom

[Guilt-Toy]

Im pretty sure there weren't any spots for them on the 30 block. Just trying to find out if there is another way around it without tapping 2 new threads in the side of my block (I dont get the car back till saturday so I'll check the block again then. Thanks for the idea tho )

Look again.

[Adriano]

I had to drill and tap for the rb26 locations, but the rb25 locations were already drilled

[rob82]

There is two mounting points on the intake side of the engine - from memory the one of them is drilled tapped while teh other is just drilled.

I just screwed my other knock sensor near the oil pan. Works fine - as much as the std ecu knock control works anyway.

[wig r31]

Thanks heaps guys. I got the car back yesterday and pulled the inlet plenum off today. the spot for them on the rb20 is just below the head but on the 30 block the spot was there but they were not drilled at all, although there was holes drilled and tapped directly below the undrilled spots (if that makes any sense) im hoping it wont cause any problems having them half way down the block???

[rob82]

Thanks heaps guys. I got the car back yesterday and pulled the inlet plenum off today. the spot for them on the rb20 is just below the head but on the 30 block the spot was there but they were not drilled at all, although there was holes drilled and tapped directly below the undrilled spots (if that makes any sense) im hoping it wont cause any problems having them half way down the block???

Half way doen the block is fine - thats where mine are!! They do f**k all anyways.

[Sydneykid]

Half way doen the block is fine - thats where mine are!! They do f**k all anyways.

Mine work very well in that location, consistent results when compared to the knock amp and headphones.

Cheers

Gary

[rob82]

Mine work very well in that location, consistent results when compared to the knock amp and headphones.

Cheers

Gary

The factory ECU will not retard the timing if it sensors detonation. From what I have seen it will switch between high and low octane maps based on knock feedback at low rpm high load. If it changes from high to low and it still continues to detonate there is nothing it will do to stop it. So in a sense they do f**k all.

[Adriano]

Although with the stock maps, or good aftermarkey mapping of th estock ecu, there is no way it will knock on the low octane map, its a hell of a lot better than what a pfc or most aftermarket ecu's do

[JCaSs1001]

can ne 1 show which holes the standard knock sensors go and which 1ns half way down the block you are talking about ???

[GT-RZ]

can ne 1 show which holes the standard knock sensors go and which 1ns half way down the block you are talking about ???

at the top of the block you see six 'casts' the top three are blank and the bottom three are tapped. the one on the left and right are used.

[cdorhout]

I drilled and tapped the higher locations for my knock sensors, the thread pitch is 1/4 BPT by the way.

I run a PowerFC and rely very heavy on my knock sensors, so I wanted them to be as accurate as possible. Plus, it's very easy to drill, tap, and install.

[Adriano]

The rb26 knock sensors are m8 x 1.25

[GT-RZ]

I used the top ones also but only because the 26 thread is a different size (like adriano stated) if you are going to use the 25 ones i don't see the point. accuracy would be exactly the same IMO.

[proengines]

I attached a photo showing both 25 and 26 positions. The block is in the mill to spotface the pads for the 26 sensors which are drilled and tapped M8.

[JCaSs1001]

I drilled and tapped the higher locations for my knock sensors, the thread pitch is 1/4 BPT by the way.

I run a PowerFC and rely very heavy on my knock sensors, so I wanted them to be as accurate as possible. Plus, it's very easy to drill, tap, and install.

did you actually notice any diffrences by mounting them in the higher positions??

[rob82]

did you actually notice any diffrences by mounting them in the higher positions??

I could almost guarantee you that any location on the intake side of the block will work to the degree thats required for the factory ecu or PFC.

I have played extensively with knock sensor location on EJ25 block as I was experiencing spurious knock at a particular load and rpm point and found that moving the location of the sensor didn't help at all. Subarus are much more particluar with knock snesitvity than most other cars as they learn both advance and retard ignition.