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Does anyone know the specs for the stock RB25 turbo in an R33 1993 model (Series 1??) or can point me in the right direction. I've had a search and come up with nothing useful.

Anyway, What manufacturer/ model, How much power they're good for, How much boost is too much, component sizes, bearings, etc. Any & all specs.

Also a question relating to twin turbos: Is it OK to run 2 different size turbos?, say 3 cylinders feeding 1 turbo and 3 cylinders feeding the larger turbo?

I've got an R33 turbo and a GTIR turbo and I'm looking at building a twin turbo TD42 thats good down low in the rpm range as well as up higher. Basically my normal Patrol forum

doesn't cater for twin turbo info and other Skyline stuff so I came here for info.

If anyone has any GTIR Pulsar turbo info, that would be great too.

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Stock rb turbo is useless. Throw it in the bin. With the patrol what do u expect to gain from a twin turbo setup compared to a single turbo that is matched perfectly for the size and rpm of the engine?

Msg hypergear, im sure he can tell u what turbo ro use on it

Does anyone know the specs for the stock RB25 turbo in an R33 1993 model (Series 1??) or can point me in the right direction. I've had a search and come up with nothing useful.

Anyway, What manufacturer/ model, How much power they're good for, How much boost is too much, component sizes, bearings, etc. Any & all specs.

Also a question relating to twin turbos: Is it OK to run 2 different size turbos?, say 3 cylinders feeding 1 turbo and 3 cylinders feeding the larger turbo?

I've got an R33 turbo and a GTIR turbo and I'm looking at building a twin turbo TD42 thats good down low in the rpm range as well as up higher. Basically my normal Patrol forum

doesn't cater for twin turbo info and other Skyline stuff so I came here for info.

If anyone has any GTIR Pulsar turbo info, that would be great too.

2 Different size turbos in that configuration would make the thing drive really awful. Either use same size turbo for each lot of 3 cylinders or use 2 different size turbos in series/sequential etc.

But with those turbos I dont think your going to gain much/anything from a series/sequential setup. 4.2L Diesel is going to be inefficent with those turbos anyway. Do it properly or you will be disapointed you wasted your money

Edited by 89CAL

You would probably be better off looking into turbo diesel engines of your capacity and seeing what turbos they use as standard . This would give you a base line into sizing which is a good start .

Be vary carefull not to go too big on diesel turbos because you have a limited rev range to start with , also diesels mostly lower combustion temps means you can run a fair bit of boost without melting anything .

You get a bit of a free ride with detonation ignition too !

Also make sure the intercooling is adequate because diesels like good charge cooling as well .

A .

Be it myself building a truck with a RB, I would simply have the factory turbo high flowed and give a description of the desired outcome to the machinist.

I think Hypergear will honestly be a great option for you. Simply tone down your expectations for top end power as you really dont want a top end turbo in a truck. A basic highflow however might see you VERY happy.

GL

  • 2 years later...

You need to read articles about how turbos work. Have a Google.

you can't run two turbos, different sizes off only half a cylinder bank.

As for 25 stock turbos... Read the Dyno sticky thread yet?

synchronus charging?

Compound charging?

as apposed to a normal twin charging..has been done before, tho this is a waste of time in this situation specially with these 2 turbos..

build something like this in stead :)

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