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fitting vg30det and rb25det turbos

Mase

By Mase,
in Engines & Forced Induction

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Mase Mentor

Mase

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Could anyone who has done the conversion of vg30det onto an rb20det please supply a few hints and tips. I looked on meggala's site but was after some more info please people. Also, will a vl turbo fuel pump be able to keep up with this turbo happily running up to 12psi boost??? I know you need to rotate the housing on the turbo or something and the oil and water lines won't match up.

For those who have done the rb25det turbo on rb20det could you please list the procedures also.

Im having a lot of trouble finding an rb25det turbo at a reasonable price so im thinking of opting to the vg30det even tho it's a bit laggier. All info would be greatly appreciated.

Thanks heaps people, things are starting to look up for my car now i think.

Jayson

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Mase Mentor

Mase

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Well thanks everyone for your help. Im doing the thing and finding out for myself, will post information as soon as it's done and i've finished having fun with it. From what i have learnt so far, (rb25det turbo on rb20det) run the line from the wastegate to where your boost guage plugs in at the back of the manifold to save tapping into your intercooler pipes. To keep your boost guage just put a T- piece in there. You will need the rb25 lower intercooler pipe cuz the rb20 one won't bolt straight up. I think i may need a different thread size for the water piping but i'll get into it when i get up to it and last but not least, rusty bolts are a real bitch, expect to break a few.

Part 2 coming soon.

Jayson

ps. by the way, i went for the 25 turbo as my car is sluggish off the start as it is and putting a vg30det turbo on there would of made it worse.

BOOSTD Mentor

BOOSTD

Posted
Posted

Straight bolt up for all!!

VG30bb will have no more lag, but, make less power than RB25

VG30 non bb has a bigger exhaust wheel and makes more power than the RB25 but is laggier

Intercooler pipes don't need to be changed as the Tri bolt flange on the comp housing will bolt up to any of the RB turbo outlets.

Mase Mentor

Mase

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or you can just t-piece it off where you plug your boost guage in on the back of the manifold. I have tried lining up the flange from the intercooler piping from the turbo, to the connector that the intercooler hose goes to and the rb20 unit's bolts don't line up as the unit is smaller. Will take pics later to show you. Mine is a series 2 r33 turbs.

HRthirtyone Rising Star

HRthirtyone

Posted
Posted

just drill and tapp the outlet pipe, screw your "nipple" in that for the boost line that goes to the wastegate on rb25 turbs. Thats what i did, works fine. Just remember to drill a hole in the thick side so you actually have something to make a thread in...

Mase Mentor

Mase

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yeah i wasn't gonna be running anything silly. Stock boost till i get a boost controller and front mount then nothing too much. Got dramas now, i don't have the pipe that bolts to the turbo. The one which the cooler piping goes onto. The rb20 one is smaller and nobody has one around. Think one might need to be fabricated which means more cash. grrrrrr

Mase Mentor

Mase

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Alright, all is sorted!!!! Does ur's run 0.4 bar stock??? Mine does. I got the r33 piping off the guy who i bought the turbo off for free so it's all good. Can't wait to go out tonight in it. Missed my car!!!! hehe The turbo went on with the only problem being the wastegate vacuum line which i simply T-pieced off with another vacuum line just above it on the cooler pipe. Will post pics maybe.

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