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How-to: bolt a VLT turbo onto your RB25DET

Revhead

By Revhead,
in Engines & Forced Induction

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Revhead Grand Master

Revhead

Posted
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Posted
When I read the post heading I thought WHY WOULD ANYONE BOTHER? :looney:

But then 7 posts later, all was revealed :idea:

So I gotta ask, why didn't you put the T4 internals in the R25 turbo?

SK - I got the turbo for the cost of a bog stock, NA RB30 long motor (~$350 from memory). It had already been modified by the previous owner, who had it on a VL. Far, far cheaper than modifying my existing turbo.

Wouldn't the aerodynamics be a moot point, with both wheels having been replaced as part of the rebuild? Or am I missing something?

PS, I mentioned that it had T4 internals in the first post :rofl:

Sydneykid Grand Master

Sydneykid

Posted
Posted
Far, far cheaper than modifying my existing turbo

I would have removed the T4 internals from the VL turbo and stuck them in the RB25 turbo. All you would have had to do was machine the RB25 turbine cover. Coupla hundred bucks with new seals and gaskets. Maybe worthwhile thinking about. :rofl:

DETurbine Enthusiast

DETurbine

Posted
Posted

so how efficient is the stock R33 turbo?

I have been wondering myself. Some say 12psi and others say 15psi.

Around here people are craving these ball bearing turbos and I could sell it for $350-400. Sell that and just spend another $200-150 on top of that profit and get a T3/T04e .63ar, which would bolt right up and could make around 500HP. There is a shop out here in the states that is running to same turbo on the stock manifold (moded with an external wastegate) and custom down-pipe. They have a Apex'i S-AFC, 720cc injectors, 6puck, and FMIC and are making 450rwhp.

93RPS13 Enthusiast

93RPS13

Posted
Posted
There is far more to a 0-100 time than the turbo, vehicle weight being the most obvious, followed closely by engine capacity.  So comparing a VLT with an R33 GTST really is a waste of time. :headbang:  

To answer your question, I have an RB20DET with an RB25DET turbo on it and I wouldn't even think of taking it off and puting a VL turbo on.  The average power would suffer greatly, plus I would have to change a whole pile of stuff to get it to fit.  The big advantage of the RB25 turbo on the RB20 is it fits straight on.  Just swap over the wastegate actuators (the RB20 one has a higher spring rate). :)

how fast is that RB20 with the RB25 turbo on it?

  • 2 weeks later...
WLD747 Experienced

WLD747

Posted
Posted

i think this thread has moved it focus from a rb25 to a rb20. So to get things going. Is it a waste of time to bolt on a standard vl turbo onto a r33? Wouldnt the bigger exhaust housing and steel wheels make it an advantage over the rb25 turbo and thus more boost and power? The standard rb25 turbo has fantasic response but lacks top end power which would be useful from a vl turbo.

:D

Sydneykid Grand Master

Sydneykid

Posted
Posted

We have found no noticeable difference between any of the RB25 turbos as far as boost, power or breakage is concerned. The compressor being plastic is a non isssue, it's the ceramic turbine that matters. And they all have it. :chop:

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