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VCT question. Does anyone know where the hydraulic valve(ram) is on a R33det that controls the flow of oil to the camshaft phaser.

Need to know where to feed the oil to, as I believe I will be welding the vct oil gallery on the head

thanks

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I must be a retard because I cant find what I am looking for even though I am sure its somwhere...

If I am going to put forged RB25 pistons (20 thou oversize) and eagle rods out of the same motor into an RB30 block, will comp ratio still be reasonable (8:1 or 8.5:1)? This combination will be fine I assume as in the .pdf its stated that bore is the same between 25/26/30. The rods are my concern but I am pretty sure they are interchangeable.

Sorry guys >_<

This is the wrong way to build the engine. The RB25 pistons have a lower compression height than the RB30 pistons, so they will be down the block about 0.5mm. The pistons have an 14cc dome on the top of them too. Assuming you deck the block to 0 thou you would have a cr of around 9.8:1, possibly higher if you have the head skimmed to make it dead flat.

Not machining the block to 0 thou deck would give you a little more chamber volume but this would also make the engine more prone to detonation as the sqush pads in the head are way too far away from the squish area on the pistons to make the combustion chamber efficent.

The ideal engine has a 0 deck height and a 0.040" (1mm) head gasket. Then set your desired CR using dished pistons after having your head cc'd. Using RB30 pistons gets you close to 8:1 depending on your head cc.

You should read the PDF file, it covers the options for piston choice.

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how have people fixed their throttle cable issues. i have a q45 TB on a greddy plenum and using the stock throttle cable bracket i can hook up the cable but there is too much slack in the cable itself.

i heard you can get replacement disks that the throttle cable hooks onto on the throttle body so you can rotate it further to take up the slack. does anyone know where to get these? or am i better off getting the cable modified?

Edited by TiTAN
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  • 3 weeks later...

car is running and has an initial tune on it.

Arias 9.2:1 comp pistons

Stock RB25 cams & springs with slightly cleaned up ports (completely stripped and rebuilt head)

VCT enabled

Greddy intake with Q45 TB

GT3582R 0.82 on an ETM manifold with 4" dump pipe, 50mm external wastegate

The engine is so much nicer off boost than the RB25 ever was and once its on boost the thing flys (making ~5psi by 2300 in 4th)

290kw @ the rear wheels 18 psi and bugger all ignition timing, 11:1 AFR up top and not making use of the WMI as something is leaking into the intake and fouling up the plugs/ deploying a smoke screen (to put it lightly) on the over run (PCV leaking oil, valve guide/s leaking oil, brake master cyl faulty and leaking fluid) any or all of the above. so we cant lean on it till thats fixed, should have an easy extra 70 or so kw left in it.

post-32350-1255439935_thumb.jpg

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  • 4 weeks later...
how have people fixed their throttle cable issues. i have a q45 TB on a greddy plenum and using the stock throttle cable bracket i can hook up the cable but there is too much slack in the cable itself.

I have the same TB with a CPC plenum where the rb20 and rb25 accel cables wouldnt reach. I found an Aussie R31 Rb30 cable that requires no mods to fit.

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when i bougt mine 2 months ago

ATI917752 $1035 + GST/nil stock. (RB26, direct bolt on,-R32 for cars making 600-1000HP)

ATI917753 $1035 + GST/in stock. (RB26, direct bolt on,-R33-R34 for cars making 600-1000HP

form rocket industry's

Make sure the one your getting has serpentine belt drive unless it's a race car

But u can get them at perfomancewholesale.com.au for around 1000

cheers

can somebody tell me the difference between those 2 items.

just looking on the ATI website now, and they have an "r32 model" and the newer..

shouldnt be the same?

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Not sure if this has been mentioned...

I recently got my RB25/30 running (last Tuesday). I did the mod for the VCT, however, all I did was grub screw the hole in the head, with no other modification. My VCT works perfect. No oil control/lack of oil issues or anything (this was mod was done on the advice of my engine builder).

Discuss.

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