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hey guy's just asking the turbo guru's here if its possible to correct the massive mix match in housing/wheel design that is present in the gt2876r... the turbo is strapped to a rb25 and is rediculusly laggy for not alot of power or "punch" spec's are :

Turbine

-Wheel: 53mm w/ 62 trim

-Housing: .64 ar

Compressor

-Wheel: 76mm w/ 48 trim

-Housing: .70 ar

4inch front mouth

its for a moded std manifold...

please no suggestion's of changing turbo's etc at this time, as i would like to explore the possibility for changing housing's etc...

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say for example, 1 bar actuator presure. 2nd and 3rd gear approx fullboost @ 4500 rpm... this is untuned though, running old tune from std turbo, however i cant see the turbo getting anywhere below what i'd be happy with...

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Your call but your not going to fix that thing with housing alterations , the only genuine option is a larger .86 A/R turbine housing and that will only give it more turbine lag .

The problem is it has a modern low blade count light weight 54mm diameter turbine trying to drive a dinosaur 76mm T04S compressor wheel . Changing housings won't alter the fact that its compressor is a really bad match for its turbine .

Why Garrett continue to sell those POS things I'll never know .

IMO it has to go if you want you car to be lots better .

Sorry , A .

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Are you sure about that turbine trim? It should be the same as a 2871 rear end.

The only way you could make that turbo usable is to replace the whole front end. I would suggest .5 A/R generic t04e comp cover and backing plate, with a 71mm 52 or 56 trim compressor.

By the time you get the work done and supply the parts it'd be cheaper and easier to just find a second hand replacement 2871 on NS and sell yours. They all seem to be going bigger these days for some reason, you may even find a sucker to buy yours :thumbsup:

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By the time you get the work done and supply the parts it'd be cheaper and easier to just find a second hand replacement 2871 on NS and sell yours. They all seem to be going bigger these days for some reason, you may even find a sucker to buy yours :D

no way.......NS members are way too astute than to buy a 2876 - thats only something a skyline driver would buy :laugh:

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