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Rb25det Questions About Vct Delete And Oil Restrictors

imthinkinrbs

By imthinkinrbs,
in Engines & Forced Induction

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imthinkinrbs Explorer

imthinkinrbs

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im in the middle of assembly on my fully built rb25det. im using kelford cams with hydro lifters. the cams require eliminating the vct.

do i need to block the oil feed for the vct in the block or not? whats all need to eliminate the vct besides a cam gear?

what should i do with the other oil restrictors? im going to run a external head drain to oilpan.

please help me asap i want to get this thing together.

Dale FZ1 Veteran

Dale FZ1

Posted
Posted (edited)

Insert a grub screw into the VCT feed in the top of the cylinder block.

Eliminate the VCT solenoid in the head, and use a bung.

Tape the solenoid connector out of the way on the main harness.

Run 1.6mm restrictors in the front and middle oil feeds, and install 2mm shim (2 washers will do) under your oil pump relief spring.

Forget the extra external drain, and drill out the internal drains in the head and block.

Worked for me with doing a 30DET build using fixed cams.

Edited by Dale FZ1
imthinkinrbs Explorer

imthinkinrbs

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Insert a grub screw into the VCT feed in the top of the cylinder block.

Eliminate the VCT solenoid in the head, and use a bung.

Tape the solenoid connector out of the way on the main harness.

Run 1.6mm restrictors in the front and middle oil feeds, and install 2mm shim (2 washers will do) under your oil pump relief spring.

Forget the extra external drain, and drill out the internal drains in the head and block.

Worked for me with doing a 30DET build using fixed cams.

is the shim still needed with an n1 oil pump?

if i block the vct feed on the block . then the only other oil feeds are the middle ones , are those the ones i should use 1.6 oil restrictors

Dale FZ1 Veteran

Dale FZ1

Posted
Posted

Don't know about an N1 pump, I used stock. The shims in that setup offers a slight increase in pressure.

The RB25 block has 3 feeds - rear, middle, and front. The front does the VCT. I used the 1.6mm restrictors in the rear and middle. I wouldn't go any smaller than that when using hydraulic lifters or else face bleed out problems and noisy lifters at idle and when cold.

JonnoHR31 Grand Master

JonnoHR31

Posted
Posted

factory 25 is 3x1.5mm feeds afaik. so if your blocking the vct then leave the other 2 and it should be about right. altho if your using the 25 block you dont have to block the vct feed, just unplugging the solenoid would work.

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