[Rb26 Cam Timing Adjustment To Reduce Lag]

As Ian said... you've several issues. main two being that exhaust and the timing. A whole tooth has all sorts of wrong going on mate.

When the tuner only managed 300rwkw at 20... what was discussed? What areas did he say needed attention?

To be honest we didn't discuss it, like i said im new to rb26's and was not sure to expect but its obvious from the replys that there s something wrong.

I will check timing etc and make sure its all ok but if anyone can advise of anything else to look for that'd be great!

[Rb26 Cam Timing Adjustment To Reduce Lag]

what boost controller, what rear housing on the T04z?

Hi mate its not a t04z its a little bigger, its a 70mm billet which i think is getting close to a t51r kai the ex housing is a 0.81. and the boost controller is a Greddy profec B spec 2.

Cheers

[Rb26 Cam Timing Adjustment To Reduce Lag]

no cat either

[Rb26 Cam Timing Adjustment To Reduce Lag]

Its either got a boost or exhaust leak somewhere on the pressure side, or something is massively wrong. Only 400hp from 20psi with a monster turbo that should make near on 800+ flywheel hp just isnt right.

Pressure test the intake from the compressor housing intake and check for air leaks.

Examine the exhaust manifold with a microscope looking for signs of carbon. A leak between the head and the turbine housing will cause this. Also check the wastegate-manifold gasket, and make sure the gate is actually closing properly.

Pull the radiator and re-set your timing to 0-0. A full tooth out is something like 14 degrees from memory, which is FAR too much of a change. Your luckly you havent killed/bent something already.

Check your cat for blockages and upgrade that exhaust. You should have at least a 3.5" on it, but it will need a 4" to come close to reaching the potential of the rest of the setup. And definatly upgrade that intercooler too.

While its all apart, compression test it as well, just to get a picture of what the ring seal is like.

Im new to GTR's and RB26's and ive followed some of your posts and know you know your shi't so i'll go and check the cam timing, i was quiet dissapointed with the power output myself as I have spent quiet a bit on a combo that i thought would make alot more HP. Im sure its not just in the tune and I agreee that in must have a problem somewhere hence asking on SAU.

Cheers for your input, get back to you soon!

[Rb26 Cam Timing Adjustment To Reduce Lag]

Ok so the motor has ross pistons, spool rods, main studs, head studs, steel head gasket, 4 inch dump pipe, profec b boost control, tuned two days ago by Matt at PITS, made 400 rwhp on 20 psi.

Should make 650 -700 quiet comfortably when the cooler is changed.

Reving it to 8500 as it only has a N1 oil pump.

The biggest downfall i think is the standard intercooler atm.

The other thing that needs to be changed it the rear half of the exhaust as it is only 3" but I dont think that is the cause of the lag.

The turbo has a 0.81 exhaust housing aswell to try to keep lag to a minimum.

If I cant get much of an imporvement with cam gear adjustment and cooler I think i'll have to go for a stroked rb30. But i'd like to try to improve this setup as its all brand new!

Im also very aware of piston to valve clearances and retarding exhaust timing will only give the valves more clearance if anything.

Thanks for everyones feedback

[Rb26 Cam Timing Adjustment To Reduce Lag]

Edit on the first post, ment to say retarded the cam timing on the rb30!! not advanced it 1 tooth

[Rb26 Cam Timing Adjustment To Reduce Lag]

So I just tried retarding the exhaust cam only, took it to 4 degrees on the cam so 8 at the crank, it definatly makes it boost earlier i'd say 500rpm and much more driveable down low like from a stand still.

I should have the inlet cam gear tomorrow so i'll try advancing that gear a couple of degrees and see if that brings the midrange on harder and boost earlier again.

Cheers

[Rb26 Cam Timing Adjustment To Reduce Lag]

Hi guys and gals, so I have built a new forged RB26, with 270 10.8mm tomei cams and a 70mm billet turbo (slightly bigger than a t04Z), problem is its very laggy, it starts to make boost around 3500 1-2 psi but takes till about 5700 to get up to even 8-9 psi and then full boost of 19 at about 6500. I have adjustable cam gears and want some info on how advancing or retarding inlet/exhaust mght help my lag problem to make the car more responsive.

Im quiet aware that big turbo = lag, but this is a bit frustrating.

I had an rb30 with t04z and it would not come on boost with your foot on the brake and flat out on the gas standing still. We went drag racing and it ran a 13.6, spoke to a guy in the pits who said to roll the cam 1 whole tooth to advance the cam timing, next pass was an 11.1!!! It came on boost at least 1000 rpm earlier!

So just want to know if it might work the same way with this engine. Any opinions would be appreciated..

Thanks Christian

[Cam Gear Adjustment To Reduce Lag.]

Hi guys and gals, so I have built a new forged RB26, with 270 10.8mm tomei cams and a 70mm billet turbo (slightly bigger than a t04Z), problem is its very laggy, it starts to make boost around 3500 1-2 psi but takes till about 5700 to get up to even 8-9 psi and then full boost of 19 at about 6500. I have adjustable cam gears and want some info on how advancing or retarding inlet/exhaust mght help my lag problem to make the car more responsive.

Im quiet aware that big turbo = lag, but this is a bit frustrating.

I had an rb30 with t04z and it would not come on boost with your foot on the brake and flat out on the gas standing still. We went drag racing and it ran a 13.6, spoke to a guy in the pits who said to roll the cam 1 whole tooth to advance the cam timing, next pass was an 11.1!!! It came on boost at least 1000 rpm earlier!

So just want to know if it might work the same way with this engine. Any opinions would be appreciated..

Thanks Christian

[R32 Gtr Autometer Tach Haltech E11V2 Problems]

I have wired an Autometer tacho into my GTR using pin 7from the ECU, (yellow with red trace?) and the tacho will still not fire up. The Haltech is set up using the PWM output 1 as a tacho out and I have tried changing the out put voltage from 5v to 8 and 12v but no change.

The tacho is probably an 03 model.

An I missing something or is the tacho cactus.

Any help would be appreciated and I've searched everywhere else!

Cheers Christian

[Tomei 280deg 11.5mm Rb26 Procams]

Hi mate have you sold the camshafts?? Thanks Christian

[Rb30 26 Head With Standard Rb30 Pistons, Possible?]

Like the title says I want to buy a pre built rb30 which was built for the single cam head, I want to know if you can direct fit the 26 head with the single cam pistons. Its going into a r32 gtr with the adaptor plate. I have just come across a cheap built motor with low k's.

Any info would be great

Cheers Christian