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Rb25de Neo vct solenoid & cam gear an upgrade for Rb25det?

LaurelPWR
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LaurelPWR Rising Star

LaurelPWR

Posted
Posted

Good morning legends.

While scanning yahoo Japan auctions I came across someone selling an RB25de Neo vct solenoid and cam gear as an upgrade for the RB25det Neo... They state that the 25de vct has 30° variability and can give gains to the 25det. I'll attach a screenshot of the auction page.

IMG_2896.jpg

 

Can anyone please confirm how many degrees of variability the rb25det s1/2 and rb25det Neo vct system has??

Cheers (:

GTSBoy Grand Master

GTSBoy

Posted
Posted

I wouldn't count on it fitting older 25s.  The advert explicitly talks about ONLY putting it on Neo 25s. (and 26s as a retro with the other stuff you need to do).

I don't know for 100% sure, but I think that the difference between cam front end details on older 25 to Neos means they are not same same.

LaurelPWR Rising Star

LaurelPWR

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Yeah for sure man, Im not 100% clear on the difference in vct hardware between Neo and s1/2 either, but I think the solenoid body may be slightly different and I think the keyway on the cam/cam gear is different between the two as well so as you say, probably not interchangeable.
Still though, I'm interested in what the det Neo and det s1/2 vct variability is [emoji848] it could be a nice little gain for very little $$ for a det neo..

Rusty Nuts Experienced

Rusty Nuts

Posted
Posted

The solenoid is different and does not work in non neo engines, the vct is different too,  as GTS boy said they are specific to neo engines. Neo vct cuts in much earlier, from idle, and is active all revs to 5700rpm for turbo and 5400rpm for n/a wheras earlier RB25 ranges are 1050 - 5700 and 1050 - 5400 respectively

 

Dobz Experienced

Dobz

Posted
Posted

Neo and non neo use different actuation methods so solenoids and oil galleries are different. They are wrong to say the pulley has variability if they imply its incremental. It only phases from 0 to 30 degrees and nothing inbetween, this is a big point of confusion with the rb25 vct.

 

Rusty Nuts Experienced

Rusty Nuts

Posted
Posted
22 minutes ago, Dobz said:

Neo and non neo use different actuation methods so solenoids and oil galleries are different. They are wrong to say the pulley has variability if they imply its incremental. It only phases from 0 to 30 degrees and nothing inbetween, this is a big point of confusion with the rb25 vct.

 

Yep, it is either full on or off there is no variability . Lots of Bullsh*t floating around about this system, its quite basic.

Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted
20 hours ago, Rusty Nuts said:

The solenoid is different and does not work in non neo engines, the vct is different too,  as GTS boy said they are specific to neo engines. Neo vct cuts in much earlier, from idle, and is active all revs to 5700rpm for turbo and 5400rpm for n/a wheras earlier RB25 ranges are 1050 - 5700 and 1050 - 5400 respectively

Regardless of NEO or non-NEO the RPM where it is enabled or disabled is 100% configurable if you're not using a PowerFC or Stock ECU.

The window where it stays on should be tuned till when torque starts to decay, of course this is all dependant on what parts have been bolted to the motor.

Generally for me, I will do one run with it turned off and one run with it turned on past max torque ie close to red line and overlay the derived torque graph. The intersection point is optimally where it is turned off. Also once off, the motor will happily take more timing :)

 

Rusty Nuts Experienced

Rusty Nuts

Posted
Posted
1 hour ago, GTSBoy said:

Also, according to my quick look at Nistune just then, Neo turbo switches at 5400rpm.

I am quoting Tomei and a standard ECU there was no mention of Nistune in his enquiry. I am using Nistune in mine and using the start point at 1050rpm because the VCT internals lasts longer physically if its actuated when oil pressure is higher, they tend to "bounce" internally at idle

Rusty Nuts Experienced

Rusty Nuts

Posted
Posted
2 hours ago, Dose Pipe Sutututu said:

Regardless of NEO or non-NEO the RPM where it is enabled or disabled is 100% configurable if you're not using a PowerFC or Stock ECU.

Regardless it just doesn't bloody fit so this argument is off subject.

Rusty Nuts Experienced

Rusty Nuts

Posted
Posted
2 minutes ago, GTSBoy said:

Nistune is a standard ECU.  The ROM is sucked out of a real Neo ECU..  I just read the number off the screen.

Regardless it just doesn't bloody fit so this argument is off subject.

Ben C34 Grand Master

Ben C34

Posted
Posted
2 hours ago, Rusty Nuts said:

I am quoting Tomei and a standard ECU there was no mention of Nistune in his enquiry. I am using Nistune in mine and using the start point at 1050rpm because the VCT internals lasts longer physically if its actuated when oil pressure is higher, they tend to "bounce" internally at idle

Huh? Vct isn't active at idle as it makes the idle lumpy due to extra overlap.

never heard of anyone wearing out a vct setup..

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Rusty Nuts Experienced

Rusty Nuts

Posted
Posted (edited)
40 minutes ago, Ben C34 said:

never heard of anyone wearing out a vct setup.

I have, and they make a nasty knocking noise when they go try googling nissan vct rattle only 14700 hits

Edited by Rusty Nuts
Rusty Nuts Experienced

Rusty Nuts

Posted
Posted (edited)
1 hour ago, Ben C34 said:

never heard of anyone wearing out a vct setup.

Yes you have, you answered a similar post back in AUGUST 2015 RB25DET VCT Knocking and i quote you 

"Man, I meant the whole vct unit along with cam gear.

I thought it was kind of obvious.

Changing just the actual gear part is a bit pointless, it's the actual vct actuator part of the car gear assembly that needs to be changed"

So whats your game mate

Edited by Rusty Nuts
Ben C34 Grand Master

Ben C34

Posted
Posted

Wow. Got me there. Goes to show I don't remember everything I have said/written 3 years ago.

 

I don't think it's an issue that needs addressing or accounting for in the tune, shit just wears out.

 

My game is Q-Bert. Or Pitfall. I am a simple man.

 

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Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted
17 hours ago, Rusty Nuts said:

I have, and they make a nasty knocking noise when they go try googling nissan vct rattle only 14700 hits

Perhaps on SR20s not RB25s

Different design

Rusty Nuts Experienced

Rusty Nuts

Posted
Posted
2 hours ago, Dose Pipe Sutututu said:

Perhaps on SR20s not RB25s

Different design

different design sure! Same reason build up of sludge and /or low oil pressure. But hey, past months experience ,if I say its white you will say its black are you 5 years old.

LaurelPWR Rising Star

LaurelPWR

Posted
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Posted

G e e z u z .
I realise now the title is a little misleading... Im mainly referring to weather or not the 25de neo vct gear had more degrees of adjustment over the 25det neo vct gear... sorry I didn't put "neo" after the last "Rb25det" in the topic title.. as I stated in my second comment, I'm aware there are differences between neo ans s1/2 and they aren't compatible..

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