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If it's crap before boost I'd definitely check the timing belt is installed correctly like there saying, and then dial the cams into tomei specs and go from there, yet you need a degree wheel for the last part

No it drives nicely off boost its just when settling to idle that it jerks and shakes. Also coming on to boost feels a bit laggier but it pulls hard when boost comes on. Well I only tried it in second and i got a strong pull,

Have you also checked that it's running on all 6 cylinders and hasn't fouled plugs or left a coil unplugged

Yes all six cylinders running and coil packs plugged in.

Did the vct gear replacement got the same results idle is a bit rough and engine shakes. Also with different gear installed tried to activate the vct manually it clicked but no change in idle. Tried to activate vct manually on a friends rb25/30 as well at idle and idle didnt change. He has stock cams and we both did the internal vct mod to keep vct with the 25/30 combination.

I drove around today with vct solenoid unplugged and car drove nicely except for the shutter and jerking when coming to idle or taking off from idle.

Vct solinoid should give a small change in idle quality, I'm guessing since you. Changed the vct gear you have rechecked timing marks.

No change at all and yes rechecked timing.

Also did you bleed the lifters before installing

No I didn't bleed lifters didn't know I had to seeing as they were new and hydraulic just installed them. They seem to be primed correctly as there is no lifter tick. How would i prime them for future reference?

Sorry, I was thinking sr for a minute, Rb lifters just need to be stored in oil when out of the head,and should be bleed with all air out after idling for 5 to ten Min.

Ok cause you had me worried there for a minute. So does anyone have any other suggestions?

Even if I were to degree the cams tomei sight does not have any numbers for 264 poncams and I will only be able to adjust the exhaust side seeing as the intake side retains vct pulley. The timimg has been done over and over again and it is on time. The symptoms of the car does point to vct always being enabled as I can drive around with the solenoid plug off and car is not sluggish at all.

Do you think that somehow by doing the internal vct mod it is now constantly activated?

Are there any other test I can try to confirm vct is always engaged?

What vct mod did you do

The internal one. Where you remove the brass plug from underneath the intake cam groove at front of the head and drill holes in that same brass plug to allow oil to get to the vct part of the cam.

http://www.sau.com.au/forums/topic/251669-rb2530-rb30det-vvt-internal-oil-control/

tps voltage sitting right at idle? (0.45v-0.55v) and what rpm is idle set to? injector latency and size?

Will check tps voltage at idle, rpm is set to 900, injector latency is .34 and size are 700cc, Tried moving the latency around and injector size to tune it out with no luck. The car ran fine before cam install. Never tested the vct before so that may not have been working from engine was put together, Just assumed it was because the solenoid activated, but the displacement of the 30 bottom end may have made up for the lack of vct and just happen to realize the vct mod didn't work now because of the current problem.

Edited by Daboss

so your idle mixtures are still alright? what are they? we found some plugs had cracked porcelain today when we were tuning an rb30det.

At first the car didn't want to start had to give it gas and hold the accelerator down in order to keep it running. That's why timing and bent valves were assumed, but did test to make sure both were in good order. After a bit of tuning on the hand controller according to the wide band sensor afr's are around 13 at idle.

hmmm tricky ay...vacuum leak? thats fairly rich for idle.

Maybe but it doesn't hunt around and I put it to that afr I can lean it out more its just the best feeling afr for idle to me. But its no problem leaning it out idle gets really bad in the mid 14's.

Not sure what the problem is but i can confirm the tomei cams 256 8.5lift dropped my comp from 175 to 150psi, so that part sounds normal.

Me either that's why I am going crazy. Thought it would be a simple drop cam in job. Like I said it revs ok and driving around off boost is good as well its just when idling or coming to idle it sucks. With vct disconnected on a 25/30 can anyone confirm that it feels like a pig to drive down low?

Edited by Daboss

The reduced vacumn you have mentioned could point toward a vacumn leak, id spray some carby clearner and test it, can remember similar with mine when it wouldn't idle, does it try to stall when reversing on 1000rpm or take off? old plenum gaskets can leak when your pushing boost.

Edited by AngryRB

The reduced vacumn you have mentioned could point toward a vacumn leak, id spray some carby clearner and test it, can remember similar with mine when it wouldn't idle, does it try to stall when reversing on 1000rpm or take off? old plenum gaskets can leak when your pushing boost.

So the 264 cams wont reduce vacuum?.

It will take off at idle just using clutch but it is very jerky. Will test thoroughly today to make sure.

Carby cleaner test is just to spray around plenum and listen for idle change?

as far as the vacumn , with my 256's it was around the neg 20-25, when there was a leak it did hover around neg 10, also if the timing was retarded it would too

Mine was jerky when taking off which the tuner mentioned was the TPS that need a tweak and yes spray some around the plenum and joints and see if it gets sucked in and changes the idle...

Probably best to get a tuner to look at it though, you might end up doing damage if giving it some..

Edited by AngryRB

Yeah ahhh no such luck with the tuner as we don't have local tuners down here have to fly them in periodically as a group and who knows when the next time is.

I thought the overlap of the bigger cams would cause less vacuum.

Going to check tops voltage and do card cleaner test and let you guys know the results.

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