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Huge or Extream would be good words to use for LAG when bolted on a RB26DETT but when it comes on boost it does rip you back in your seat unlike it's little brothers. Great on fuel as a day to day driver as you hardly get to use the last 3K of your RPM's going to work and what not.

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RTF you've probably hit it on the head lol. Sounds like the turbo won't kick in until late 4k to early 5k rpm if I am lucky so that should be a fairly fuel saving LOL.

One question though, does twins necessarily means it will come on boost quickly? I am looking at a pair of GT3071R (http://www.atpturbo.com/) GCG is their reseller here in Australia.

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SK always anaylising that step further..

If you want the right answer, first you have to have the right questions. Then you have to have the data. Without data you are guessing, and I try to never guess.:rofl:

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I have a turbonetics t66 with a 1.0 p trim wheel on the exhuast side ( think very similar to a T78 ) on my 2.6ltr wrx and it starts to pull at 4500 rpm. but it comes on hard picks up acouple of hundred h.p in 500rpm. i supose it depends on what you want to use the car for. I would like to put a set of twins on my gtr but the cost is a bit much. go the big singles they rock.

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What spec of T78?

What other mods?

What do you use the car for?

T78-17.0kmg2 (or whatever that is)

Actually there's not much mods left once the stock turbo is taken off besides the fuel system been looked after. At the same time fitting the T78 I'll be dropping in a set of Tomei Poncam (260/260, lift 9.15) and spocket and a PowerFC.

What the car for? Bit of track, bit of drag just a bit of everything so it's gotta be an all-rounder or the least compromise of each the possible.

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dude,

with the 17cm^2 exhaust housing, it would not be a very user friendly street car.

you'd be looking at fullboost at about 5000-5500rpm if not later.

if possible, fit a smaller T78 housing or get a garrett A/R .82 (T04) adapted/machined to suit and it will be heaps better for the street and the track.

or better still, i fu haven't bought it yet and are looking to go single, the new Garrett GT35 (A/R .82 exhaust housing) would be awesome. nice spool up and heaps of air-flow.

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T78-17.0kmg2 (or whatever that is)

Actually there's not much mods left once the stock turbo is taken off besides the fuel system been looked after. At the same time fitting the T78 I'll be dropping in a set of Tomei Poncam (260/260, lift 9.15) and spocket and a PowerFC.

What the car for? Bit of track, bit of drag just a bit of everything so it's gotta be an all-rounder or the least compromise of each the possible.

A T78 on a 2.6 litre is not good for any type of circuit work. Have a look at the quick Japanese circuit Skylines and they run around the 650 bhp mark. Bottom line, there are more suitable turbos for your requirements.

Hope that helps :rolleyes:

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LOL...i was watching an Option DVD and there was footage of workshop cars going head to head, try WRX with TD06-25G, Jun R33 with T88! Plenty of these Jap cars used big ass singles, then again there were GTRS using 2530s as well. Interesting thing was pn the Apexi Drift RX7 i noticed some nitrous solenoids in the engine bay so i wouldnt go trusting too much of what you see going on in Japanese engine bays.

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LOL...i was watching an Option DVD and there was footage of workshop cars going head to head, try WRX with TD06-25G, Jun R33 with T88! Plenty of these Jap cars used big ass singles, then again there were GTRS using 2530s as well.  Interesting thing was pn the Apexi Drift RX7 i noticed some nitrous solenoids in the engine bay so i wouldnt go trusting too much of what you see going on in Japanese engine bays.

Hi Roy, we could go around on this one all day. The Jun GTR isn't 2.6 litres, the works HKS driver uses N1's on his R34 GTR for around 600 bhp. He could have a T51 if he wanted. Plenty of people have tried, but as far as I know the GTR lap record at Tsukuba is still held by the Mines GTR and it doesn't have a T88 or a T78 or more than 650 bhp. You might get more power from a monster turbo, but the driveablity goes out the window and as you know lap times are more about the total engine package than outright power. :rolleyes:

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Aren't the big singles that are being discussed here plain bearing, as opposed to the HKS GT-series and the N1 turbos which are all ball bearing, afaik? Wouldn't that mean that the drivability/torque delivery is more to do with turbo technology than being twin vs. single?

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