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Hi all,

I've been looking at a few interstate cars recently with the view of potentially getting one into Victoria.

Based on what I've read the authorities take a fairly dim view on top mount turbos here.

What's involved and how labour intensive is it to relocate a turbo from top mount to low mount location? It's an RB25DET with a top mount T3/4.

Obviously you'd need to confirm upfront that the turbo fits in the low mount location in the first place (not sure).

Other than that I've worked out that you'll need at least the following:

- exhaust manifold

- exhaust flange

- some new intercooler piping

Anything else? Can this be done without pulling the engine out, and how much work is involved?

Would it be easier to just throw in a stock RB25DET turbo & manifold?

Cheers

IMO it depends on what is used on the "T3/4", if it is using a large .7 A/R front comp housing then low mounting it still lets it be fairly obvious.

I was failed for having a GT30 low mounted, they worked it off the comp housing being far to large (compared to a factory one), and it was downhill from there (external gate was spotted next lol)

Can easily be done without engine out mate. Plenty of room to get in and around it all with just a trolley jack... a hoist does offer advantages!

IMO get a factory manifold and a hi-flow or something. It all bolts up, looks factory and bob's ya uncle... virtually undetectable 250rwkw.

Then sell off the high mount setup to someone else and recoup a bit of the cash.

Obviously the injectors/ECU will be picked, but they are easy to swap compared to a turbo and so on.

modified dump pipe.

new exhaust manifold

modified intercooler pipe

possibly modify the oil/water lines

modified intake pipe

You don't need to remove the engine it just takes time (or money if you are getting a work shop to do it)

If it was me and its a plain old T3/T4 i would just get a highflow stock turbo/manifold/etc and run that instead, same power but looks stock.

IMO if its a t3/t4, then check what turbo it actually is, sounds chinese, so you would be cheaper/better off buying a stocker and getting the turbo highflowed, exhaust front mount, stock airbox, clutch, nistune 250rwkw and almost undefectable

Thanks guys, that was mighty quick!

IMO it depends on what is used on the "T3/4", if it is using a large .7 A/R front comp housing then low mounting it still lets it be fairly obvious.

I'll have to confirm the specifics of the turbo.

IMO get a factory manifold and a hi-flow or something. It all bolts up, looks factory and bob's ya uncle... virtually undetectable 250rwkw.
If it was me and its a plain old T3/T4 i would just get a highflow stock turbo/manifold/etc and run that instead, same power but looks stock.

Ok high-flowed stock items do indeed sound like a good replacement setup.

Cheers

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