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RB20 ECU running an RB25 what to use as a VCT controller

Posted: Fri Apr 09, 2010 2:52 pm
by crans
I have my Nistuned RB20 ECU running my RB25. No problems there apart from no VCT.
I purchased an built the Jaycar RPM switch and it is useless. It activated on a rising or falling signal no just a window.

So basically if you drive off normally it hits say 1800rpm turns on the vct then hits say 4800 it turns it off. Yay thats fine and works well. Problem is unless you bring the revs back down below 1800 vct wont active again.

Is this correct or do I have my wires crossed?

Re: RB20 ECU running an RB25 what to use as a VCT controller

Posted: Thu Apr 15, 2010 12:56 pm
by crans
Any one got any ideas, alternate products?

Re: RB20 ECU running an RB25 what to use as a VCT controller

Posted: Thu Apr 15, 2010 4:56 pm
by Eric
a RPM switch sold by summit racing seems popular among the honda guys to switch VTEC

http://www.summitracing.com/parts/SUM-830452/

I have no experience with it on Nissans though.

alternatively it shouldn't be too hard to modify the code so you can use the boost solenoid output (ECU pin 25) as a VTC output. (I can probably do the reprogram/modification of the code for you if you ask nicely ;) )
But you will have to get the Nistune board reflashed to activate the modified code...

-Eric

Re: RB20 ECU running an RB25 what to use as a VCT controller

Posted: Thu Apr 15, 2010 10:14 pm
by crans
I didn't think the rb20 ecu has a bost control output

Re: RB20 ECU running an RB25 what to use as a VCT controller

Posted: Fri Apr 16, 2010 1:16 pm
by Matt
that would be R32 RB26 which has boost output (different ECU)

Image
http://www.erzperformance.com/product_p ... ent-03.htm
Buddyclub VCON

Re: RB20 ECU running an RB25 what to use as a VCT controller

Posted: Thu Apr 22, 2010 3:43 pm
by beng2k
MSD Digital Window Switch works perfectly.

Re: RB20 ECU running an RB25 what to use as a VCT controller

Posted: Wed Aug 18, 2010 5:46 pm
by foliage
Could use two switches and OR the output together, set one to rising edge and one to falling edge, might be cheaper than the other solutions.

Re: RB20 ECU running an RB25 what to use as a VCT controller

Posted: Wed Aug 18, 2010 7:41 pm
by crans
I ended up getting a MSD Digital rpm window switch and it works a treat

Re: RB20 ECU running an RB25 what to use as a VCT controller

Posted: Mon Nov 22, 2010 10:15 am
by sky_r33
where did you wire it?

Re: RB20 ECU running an RB25 what to use as a VCT controller

Posted: Wed Nov 24, 2010 12:03 pm
by STATUS
Eric wrote:a RPM switch sold by summit racing seems popular among the honda guys to switch VTEC

http://www.summitracing.com/parts/SUM-830452/

I have no experience with it on Nissans though.

alternatively it shouldn't be too hard to modify the code so you can use the boost solenoid output (ECU pin 25) as a VTC output. (I can probably do the reprogram/modification of the code for you if you ask nicely ;) )
But you will have to get the Nistune board reflashed to activate the modified code...

-Eric
its what we use if a car comes in without vct, works spot on.

Re: RB20 ECU running an RB25 what to use as a VCT controller

Posted: Wed Nov 24, 2010 1:05 pm
by sky_r33
STATUS wrote:
Eric wrote:a RPM switch sold by summit racing seems popular among the honda guys to switch VTEC

http://www.summitracing.com/parts/SUM-830452/

I have no experience with it on Nissans though.

alternatively it shouldn't be too hard to modify the code so you can use the boost solenoid output (ECU pin 25) as a VTC output. (I can probably do the reprogram/modification of the code for you if you ask nicely ;) )
But you will have to get the Nistune board reflashed to activate the modified code...

-Eric
its what we use if a car comes in without vct, works spot on.
can you provide me with a wiring diagram or explain me how to wire it/ install.

Re: RB20 ECU running an RB25 what to use as a VCT controller

Posted: Wed Nov 24, 2010 2:25 pm
by Matt
Does it come with wiring instructions? You need to find the RB20 ECU pinouts (google this or email me) and then line up from instructions to pinouts

Re: RB20 ECU running an RB25 what to use as a VCT controller

Posted: Fri Dec 17, 2010 11:59 am
by sky_r33
#59 Conncet Red wire to 12V
#60 Connect Black wire to Ground
#7 Connect Yellow wire to RPM Source


#113 Purple wire is Ground in set RPM Window but not out of the selected area.

This is for RB25DET Wiring Loom Pin Outs, I'm using RB20 ECU.... Problem resolved and VCT works :mrgreen:

PS: Use Window mode. NOT RPM

Re: RB20 ECU running an RB25 what to use as a VCT controller

Posted: Tue Apr 12, 2011 6:09 pm
by maxgohan
so that summitracing window switch does the job?

how much time would it take for a shop to wire that bad boy up??

Re: RB20 ECU running an RB25 what to use as a VCT controller

Posted: Tue Apr 12, 2011 7:18 pm
by sky_r33
Is only 4 wires DIY.