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Hey guys,

I just bought an R33 gtst and am wanting to swap some parts in the engine bay and just have some questions.

Current mods worth mentioning in relation to my question

- garrett gt3582r

- stainless high mount exhaust manifold

- greddy intake plenum

- hypertune 90mm throttle body

- siemens 750cc injectors

- custom fuel rail

I was originally going to buy a more standard r33 and do my own course of mods but got this for a good price with lots of other mods (not listed) that I could re-use.

Anyway... some questions

- I want to swap to a lowmount garrett gt3076r. The manifold I use will be a Brae Fabrications lowmount. Can I re-use the water and oil lines that are on my gt3582r turbo on the lowmount gt3076r?

- I want to swap to standard intake plenum. Is there anything that would have been swapped or changed when fitting the greddy plenum that I would need to revert to standard when going back to the stock plenum? (im thinking anything along the lines of studs, hoses, sensors etc)?

- Can I fit the hypertune 90mm throttlebody to the standard plenum? Is it worth it for this power level or should I just use a standard throttle body?

- Will the Siemens 750cc injectors & fuel rail be compatible with the standard plenum?

Any information would be a great help, cheers guys

Why bother...you're just creating yourself a headache when it looks fine the way it is..just drive the bloody thing..maybe downsize turbo to a t67 or ss2 if you want a bit more response but that's all I would do...

I had a feeling someone would say that, but I want it setup to how I would like it.. thats what modifying a car is all about. Just because I bought it like this doesnt mean I have to live it right? Ive been in two unopened rb25 / 3076r combos now and I love the response. If I was only after response I would just change the turbo but theres more to it.

I do have some reasons, besides the response of the 3076r , mainly I am after a stock looking engine bay. Atm its not very discreet with the huge high mount turbo, front facing plenum, chrome intercooler pipes as well as intake and pod. I am going for a more standard look hence why I want to return to stock plenum, return flow piping and a low mount turbo with stock airbox. (yes I know itll still be illegal with the aftermarket turbo, exhaust manifold, ewg etc, but its a lot more discreet which is what im after).

I would probably keep the intake plenum but switch to lowmount gt3076, the lines will likely be too long, your going to need the dump modified and a few intake pipes, the injectors if in the factory rail should be fine, you could run the gate off turbo housing to be discreet and use factory manifold with heatshield cover..

Yeah I was thinking of keeping the intake plenum. Its just the cast finish it isnt chromed up like a lot of them so it doesnt stand out too much. Was going to paint all cooler piping black. Might do the cam covers and plenum in wrinkle coat black.

I was thinking of running the gate off the housing , but will need to see whether there is enough room first. Im going to go a low mount steampipe, not keen on the standard manifold.

Is there any disadvantage to the lines being too long? I wouldnt of thought being too long would be a problem unless they obviously get in the way of other stuff?

Edited by Bennis

Thanks for all this info guys. Have decided to take one thing at a time. Will be changing turbo onto the current manifold first as I have learnt that the 0.82 housings are the same on both turbos (except the 3582r's is ported). So it should all bolt straight on with some minor changes to IC piping. Will be sourcing a standard rb25det airbox down the line too which I will hope to use in place of a pod filter. Havnt seen the standard airbox used before with a high mount so will be interesting to see if I can make it work.

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