202RWKW @ 18psi..... whats holding me back? ......0.48exh housing!!!!!!

[IN 05 NT]

hey guys.

just come back from having the 23 tuned,

its now making 202rwkw @ 18psi @ 7500rpm.......

at that boost level i would have been expecting more like 230ish rwkw

its not the tuner, map is perfect, smooth curve and flat afrs,

whats holding me back? (200rwkw is plenty for me, but was hoping to make that at a lower boost...)

Blake


EDIT, just dug thru and found my turbo receipt, its only got a 0.48exh housing!

[fixeruperer]

19psi you will get 230kw

maybe the tuner is being really safe ?

[Pimpin_1JZ]

Whats the timing like?

[The Real Roadrunner]

its definately not the guy punching the numbers, he is safe but not to the point where the timing would be overly retarded.

did you get him to check the cam gears? or even mention it had them?

cheers
linden

[IN 05 NT]

didnt even think of the cam gears,...... but they should be ok as they haven been touched,

202kw is the safe tune, can push a lil more out of it,

can easily wind more boost in to it, as it'll take it,

it was burning a lil bit of oil, but im thinking thats just bcoz i have only a 10w-30 in it, might go up to a 15-50 or 20/50 or similar


i cant think of anything thats holding it back?

[fixeruperer]

should, just, only, might and could are words waiting to fail.

[abently]

Look at the Turbo compressor map. Mark a horizontal line at 19psi. Now you know Power is proportional to the Air entering the cylinder. So, look at the compressor map and ask yourself why is it hitting 19psi on the left side of the Compressor island and not on the right side ? Remember boost is just a measurement of the back-pressure in your Intake system. Anyway, long story short, you need more cam or correctly ported Head. Take your pick.



/P.S. I'm assuming your exhaust manifold/Hot-side is sufficient enough to deal with the current Cam overlap.

[dfunkt]

could it just be a low reading dyno??

[IN 05 NT]

could it just be a low reading dyno??

its suposedly a TRUE dyno,

it was making 170rwkw on 10psi, if that gives any more info?

im stumped?

[abently]

Just looked at the Garrett catalogue. They only offer the 0.64 & 0.86A/R for the 3071 Turbo...... looks like you got an older Turbo.

One way to tell if you have enough cam to max out the Turbo is this. You can tell from the Compressor map max efficient power is going to happen at 24psi -2psi pressure loss, so 22psi at the Intake manifold runners. Now run it on the dyno and tune it. If the boost keeps rising (ie doesn't drop off) at say 7000rpm then you need more cam.

I suspect though its the exhaust housing. Garret when producing the Exhaust Housings do set the possible A/R's very accurately. If you like the response, then play around with the cam timing. If you wheelspin to easily, then get a larger Exhaust housing assuming it actually bolts on to the Turbo and dump-pipe.

[IN 05 NT]

spoke to GCG,

said it will need to be machined and a new dump pipe flange as on there atm is a 2.5" flange for the 0.48 rear

64 or 86's are 3"

now wether to spend the money or not......(im going to have fun driving it 1st!!!!!)

[Forcefed6]

from memory they hav done 1 set of turbo's and it was only due to getting smokey, it didn't drop the rear wheel into the exhaust.

the engine always had a funny knock in it from the start which then (over a year later) decided it would show itself as a fooked big end.

instead of just baggin out what they have done how bout you try to beat them?

btw i was there for a 314kw run from kade's car and i know for a fact the dyno is legit (my 1jz pulls 263rwkw on the same dyno and 280rwkw on the SAS dyno)

cheers
linden

ps, doubt GT25's would get you there (without nos) but a set of GT28's will

From reading this post made by Linden in another thread... I reckon that your 200rwkw is pretty well on the money for your setup, and I defiantly wouldn't be disappointed, as I imagine it would be a super fun car to drive like that.

[SillyCarS]

videos of skids/donuts/drifting/ringies ***on private property***

[SillyCarS]

increase the housing to a 64, a lot of the sr20 guys run the gt2871r with a 63 housing and make spatic powers

then shove an extra water/methanol injector before your cooler 240rwkw?

[The Real Roadrunner]

fook, didn't know you had a .48 on there.

thats way too small, get a .63 freefloat on there and it should make another 20 odd rwkw.

do you know what rear wheel it has? there are 2 different types for the gt30 1 is 60mm with a trim of 84 and the other is 56.5mm 90trim which is more like a GT28.

the 60mm is my prefered choice as its efficiency is better but either one can make 230rwkw or more.

get a .63 on there asap and it will be a shitload better both on and off boost as the .48 will be choking the crap out of it.

i can put a pressure fitting in the exhaust to test the difference if you like.

your cams will be fine for this turbo (not perfect but good enough) and i can't see the holding it back till you start getting 250+rwkw.

cheers
linden