problem with rb25det NCVT

[z-monster]

hi guys.... as most of you all know the rb25det is the only rb series engine plagued with this ncvt problem... the problem i'm facing is that after 4000rpm the second cam setting is suppose to kick in and the cam pulley is suppose to retard or advance to continue the climb in TQ and HP... i dont have my dyno chart but my car has a max hp rating on the wheel of 190hp@4125rpm from that rpm the hp and tq drops at a rapid up down rough chart movement. i was told that the problem is due to a bad cam pulley thats not retarding or advancing when its suppose to. if anyone of you guys here can give me a solution to this problem i would appreciate it. i expected to see something like 230Whp on my car that has an intercooler upgrade, HKS high flow pod filter, 0.8bar boost, and regaped iredium plugs.... 0.6mm

thank youkevin

[eh?]

Check pin 1 of the VCT soleniod and see if you are getting 12V with key on.

[GTR Shop]

The system drops power off the solenoid at ~4500rpm.The dip in torue and hp can be ironed out by leaning the car out at that point.We have been playing with the disengagement point recently and have found on the test car, 5700rpm was its sweet spot.

[z-monster]

aside from having the solenoid being the problem is there any chance of eliminating the cam pulley alltogether and replacing it with an adjustable one so that the solenoid does'nt have any influance on the cam advance and retard???? what happens if the solenoid wire doesnt read 12v??? and how to fix this problem???

[GTR Shop]

If you disconnect it, you will loose ALOT Of torque and hp up to ~5000rpm

You can get rid of it by fitting a non variable intake cam.Personally I'd try to fix the problem rather than junking something that works well on the engine.Able to post copy of your dyno charts?>

[z-monster]

hey my friend...

how do i fix the problem??? what is there to change???? is it the solenoid thats messed up of the variable cam pulley? its not the cams for sure and i doubt its due to the lack of vlotage running though my solenoid plug although i have not checked... what else is there that i can change and get this problem out of the way??? i am seriously thinking of fitting adjustable cam pulley's since its not such a expansive solution but what is the draw back of doing so???

[eh?]

There's a 99% chance it is a wire problems, from what I remember The 12v needed for the O2 sensor, AAC and nvcs solenoid needs to be wired in when doing the swap...

[z-monster]

eh?

dude you were 100% right on the money!!!!! i have a nissan 280zx 1980.. and its been 1.5 yrs since i have fitted the rb25det in it and have been using it with the Nvct disconnected for that same amount of time. its only up till friday night i solved this problem with my wire man..... the power line for these sensors were not wired up properly from the ECU!!!! this is the problem with we hybrid cars like ours!!! hybrids rock!!! hahahhah

the car feels lighter now but i feel the obvious dip of torque and hp while the cam is advancing.... how do i resolve this problem?? will an upgraded ecu do the trick??? and can i fit rb26dett cams into my rb25det??? that way i will install adjustable cam pulleys as well...

thanx guys yall are a big help.

[eh?]

You can use RB26 cams but they will need to be modified to work correctly with Hyd lifters. You are better off with a standalone ecu.

Here is a graph of a 100% bone stock RB25 vs. upgrade ecu.You can clearly see where the cam is advancing.