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Right so I'm currently running a S2 RB25DET in my R32 Skyline, As of this second its basically standard but as we all know this never lasts long. I'm currently leaning towards the new medium frame GTX series turbos with the GTX3076r standing out the most ATM. Most likely running a .63 rear as I'm more into responsive setups than lag and big numbers.

I'm 'only' chasing around the 250rwkw as I cant afford a forged build any time soon and I've heard that its a achievable number for a stock internal RB25, AND it will stay as my daily car.

The main point of this thread is about mounting issues, I know that people have problems running a highmount setup in RB25 powered 32's due to the turbos hitting the tower strut. Im also even unsure on if I want to run highmount to start with to draw as little attention as possible on 'RBT' that involve my bonnet going up.

Now what are my options for highmounting this turbo or something similar that will make that power figure without issues OR what are my options for low mounting said turbo. Possibly on the stock manifold to save some all important coin.

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You have chosen a 700hp turbo which would be way too laggy for that power. If you don't want attention go for a highflow turbo instead. (unless you are planning to push for much more later.) A smaller rear housing will just choke the potential of the compressor.

I'm thinking I wont push for more, but I can never really know. Not sure on how a 250rwkw RB25 feels but if its anything like my mates 280rwkw SR20 I'll be more than happy :thumbsup:.

And less lag/cost is always in my books. Anyone running a Highflowed 25 turbo making around that power have any imput

Ive been running on the idea that being a little more torque'y it should have a pretty close 'pull' to the SR.

I'm mainly wanting to know when boost would come on as I hate big lag. As I said I would rather less power and response than a week of lag and a big number to wank around with. I never really considered Highflowing the factory turbo due to being talked out of it by a few people I know saying they are laggy as hell.

I know he will always be faster do to weight and the fact its an insane engine/car. Not really worried about beating him just looking for similar feel in the speed of the cars.

I would be more than happy with a 12 :happy:. He is running 13.5 @ 120mph due to the fact it cant get off the line with speed.

280kw in a silvia will run a 11.0. I know cause mine ran it twice in 1 night.

Skyline will need 350kw+++ to run that time.

i wouldnt worry about trying to beat his car. Rb25 will safely make 280kw with Decent response. Will be plenty fast enough

'Rb25 will safely make 280kw with Decent response. Will be plenty fast enough'

Thats all I want out of it as a daily driven car, a bit of poke and still safe on the car. The only thing that hasn't sold me on Highflows is power delivery and 'street lag' instead of what you get as far as response on dynos. Not sure how different it would be as I most certainly no expert on dynos

U can only guess by reading. Without actually goin for a ride in ur exact setup. Its always a bit of a gamble. Just have to go by word of mouth. Find someone on here with that power and pm them to see how it feels on the road

This is a chart from when I first got my highflow installed. After I finetuned my Jaycar electronic boost controller it was a little better still and in real life on the road it was not at all laggy. If you look at the blue line you will see its at 7psi at 2750 and in fact it starts boosting from below 2000 and its at full boost by 3500. (and for Kiwi readers it wasn't tuned by Soichi but by X Tune using his dyno).

boostchart.jpg

245awkw (intercooler and ecu holding me back - I think turbo would have made 260 -270). Seemed very fast at the time .. flew up hills with a full load...but then I started doing track days so now I am going RB30.

What more can I say? As above no more lag than stock turbo but with more power. Power delivery is hard out til red line (6800). Here is a chart with an old smic but with GCG highflow (went to make 245awkw later):

post-49463-1252036610_thumb.jpg

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