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hey

im considering making a twin turbo setup for my rb25det

consisting of a pair of custom manifolds, 3 runners each

2 t3/t4 turbo's, internal gated

and then the piping to merge just before the intake for the cooler

i know people myt say stay single, but ive been through all different setups, low mount and high mounts, but jus trying something new

thanks 4 ur help

Is there a question here?

Are you after some sort of information?

Thoughts?

As there isnt a question, i can just give free thought...

I assume the motor is still internally stock.

Using TWO t3/4 butcher turbos as i like to call them is going to result in response probably equal to a T88. You are not going to see boost before 5000rpm, could be upto 5500rpm. Or more.

Most "butchers" make around 220-250rwkw... so effectively putting two of them on there is going to be a very fruitless excercise.

Many T3/4's have little thought behind them, and are also bush bearing which certainly is not going to aint you in your endeavours.

Trying something new is good, but gotta wonder why no-one else has really done it (commonly) before, its 2006 and skylines have been around for a long time now.

I assure you plenty have thought about it and realised cost and the performance isnt worthwhile just for being "different" :D

why need a massive budget.. ? sure you could go for the 2510's or gt-ss's but if you wanted to do it cheaper you could just get a pair of N1 gtr turbos, or garrett's equivalent..

fact is, toyota have done it and it worked well, i've seen a few 1jz's running bigger twins and making good power. I've driven a jza70 supra with HKS t3g's (early 2530's with smaller turbine housings and 360 thrust bearings) its a response machine and makes over 300kws.

Plus with the ports lining up on both heads, modifying the flanges on a pair of cheap gtr manifolds would cut costs even more, and the piping would be even easier!

to me it sounds like a kick ass idea, i'm surprised more people havent done it.

go for it dude!

Karlos

Edited by kwazza11

Why not put the Rb26 head on the 25 block and use the setup as if it were a GTR. You might want to bore the block out 87mm to get a little more capacity under your belt, do some major port work including larger valves and you could get that thing spooling fairly quickly on a couple of GT2530's.

But then you end up with something that looks like a RB26, but... just isn't.

The RB25DETT has been done here in Vic, however it's not running anymore.

I'm slowly gearing up to do this. I like different

Hey,

I'm actually about to try this myself, just sourcing cheap bits at the moment. My philosophy behind it, as i'm not after exactly "massive" power at this stage is to source a cheap pair of GTR turbo's and possiblie manifolds (depending on how hard it turns out to be modifying the flange on them) and doing the same mod. I trawled through a few japanese sites and found these on one:

rb25-26.jpg

although I think modifying the original ones (read: just not bolting up cylinders #1 and #5, haha not really :D) might turn out cheaper and easier than getting something fabricated like this.. Anyway the whole appeal behind the idea to me is a decent setup using cheap, quality second hand parts that are really tried and proven on an entierly new setup..

mark

Edited by aphid

2nd hand ceramic exhaust wheel on the stock turbo's sounds like a ticking time bomb to me. you really should change them to steel wheel's. one member has seen this failure destory an rb25dett before

The turbo's would be rebuilt at some stage, although the actual condition they were in when I recieved them would decide on how long that would be... I wouldn't be pushing them beyond what the acceptable limits are on the rb26 with the ceramic exhaust wheels at any rate :D

EDIT: Check out http://www.calaisturbo.com.au/printthread.php?t=13913

Edited by aphid

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