First Impressions of GT28RS

[BigMal]

Got my car dyno'd yesterday with the GT28RS on and have to let
anybody who is thinking on one that it is a fantastic upgrade. The off
the mark off-boost performance is great better than a n/a and
way better than a std BPT. Whoever said a big turbo will kill bottom
end should try this as it is amazing and thats just the beginning. The
on-boost just gets even better solid linear pull cant give an exact
when full boost comes on as have fried the insides on one of my tyres
to the belts so will get a balance and replace the tyre and will then
give it a full flat to the floor as just frying em at the moment.
By far the best improvement is from low revs round 2000rpm where a
downshift was a must with the VF8 you just plant it and it boosts right
up hard. I am sure that is a lot due to the .63 exhaust housing I selected.
The only downside and I am sure it is not the turbo is the overall HP
output. I ended up with 157kw at 15psi which is less than the previous
160kw at a different tuner and this is a way quicker than the previous setup.
I need to look for a restriction I got 142kw at 12psi and think I should get
more than 15kw for 3psi of boost in the prime of the flow map. Thinking
that maybe the 2" from turbo to i/c should be raised to 2.5" as fuel and
exhaust system is all good stuff. Will tinker with some things as time
goes by but overall couldn't be happier with this turbo. The final proof
comes from my son who 1) Screamed for everbody to jump in the car to go
for a second blast after he got in with the tuner and me for the first blap.
2) Any time he hears the turbo spool slightly grabs for the roof handle with
all his might

Regards

Mal

[sonicneo1]

hey mal,
where abouts did u score yours from? With the new ecu going in soonish i've been thinkin about maybe doing the turbo at the same time.

[Shaggy]

Good stuff Mal

[Ian]

turbo upgrade eh?

Id love too... after suspension, which is gona cost lots.

[project.r.racing]

sounds good mal, yeah bigger piping will help if 2" is all you got, with that turbo, even 3" if it could fit would be great

ryan

[Rupewrecht]

Good to hear, i was a little bit worried about what the lag would be like. Roll on payday.

Still pulling hard top end? Or running out of puff by 7000?

[BigMal]

I got it from Horsepowerinabox but first I went onto nissansilvia and looked at
the promotions which for me was the xmas deal and saved $150 off normal price.

I wouldn't say its running out of puff but it does taper off in the higher revs hence
me looking for restrictions. The dyno guy thinks head needs porting as on a CA18 with
the same bolt on goodies eg Skyline GTR injectors, 3" exhaust, GT28RS etc gets
200wkw but the CA18 head apparently flows very well. Changing the turbo side i/c
pipes is not an expensive thing to try, the turbo mouth is only 2" so technically what
I have is best for least lag but at the moment its the only thing I can think of as exhaust
is good, fuel is fine, have the GTR intake manifold and a custom exhaust one.
If not will need to wait for a year or so for me to save up the funds for a full rebuild.

[BigMal]

p.s just to clarify my I/C pipes are only 2" from turbo to I/C ie hot side and then are
3" from I/C to intake. So its only the small bit of pipe on the drivers side thinking of changing.

[Nate]

i can see why you are thinking of changing that thru the process of elimination, but is that really going to make a positive difference? i mean your turbo mouth is only 2ish and the air still has to get thru that so wouldnt you be better sticking with the 2 inch hotside pipe to keep the velocity up? i could be completely wrong here but that is jsut my 2 cents. hope you get the issue sorted out anyway.

The upgrade soundsawesome! have you got any dyno seats or pics of the new boostenator??? deffinately looks like you have your hair dryer set on hi now

PS - you better been around when compact acttack is on at the end of may i have been to sydney so many bloody times and have had the pleasure of meeting you but still havent seen your car!!!!

[Exodus323]

i can vouch for how much power the car has picked up with a proper tune.
I have never seen a astina pick up as much speed so quickly as what mals car does now.
The sound that the gt28rs makes is awesome.
Now i carnt wait to begin my conversion.

[Nate]

do it paul do it!! you car already looks sweet, now give it some serious power!!

[BigMal]

Nate
Logic says that a cat back system shouldn't make any power as the pre-cat
pipe is the same so should limit the flow but we all know it makes a diff so
hoping for a similar effect by upping the intake pipe.
Also I will start making appearences again, been embarrased of the car since the guy
reversed into it and smashed it up more but now I have basically done all my engine
mods so can hopefully start on the bodykit and bonnet and then get it straight again
and all one colour.

[89sp1.8]

sounds nice man,keep us posted on upgrades

[Shaggy]

Mal can you get any vids?

[BigMal]

Not of the dyno run no.... didn't think of it at the time

[Exodus323]

HAhaha i will nate in june i will complete the conversion when i come back from holidays

[BigBoyLemonade]

Good to hear that Mal's astina lives on! A polish and port with some bigger cams would make a huge difference inconjunction with the turbo. Well done, I will have to come up and visit for a ride!

[Nate]

Originally Posted by BigMal

Nate
Logic says that a cat back system shouldn't make any power as the pre-cat
pipe is the same so should limit the flow but we all know it makes a diff so
hoping for a similar effect by upping the intake pipe.
Also I will start making appearences again, been embarrased of the car since the guy
reversed into it and smashed it up more but now I have basically done all my engine
mods so can hopefully start on the bodykit and bonnet and then get it straight again
and all one colour.

yep thats a good point mal! and dont be worried about a few dings, you should see my beast these days lol

[BigMal]

With the way it goes now I pretty much couldn't care less what it looks like
any chance to take it for a drive puts a smile on my face

Tony... Anytime man, am always happy to take you for a blap remind you what a
Turbo Astina feels like.

[Exodus323]

Apperntly you shouldnt polish a turbo head only port it.
The reason being when its not polished it helps with the swirling effect that you want when you have a turbo.
This infomation is from a man that owns a tuning shop and he knows his ****