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i got my car dynoed,

r33 gtst with

fmic,

3 inch exhaust all the way with standard dump pipe,

boost at just under 10psi

it was running well, richened up a bit at the end, which i was told was fine.

But why the huge loss of power thru the drive train??? if it has 200kW i was expecting a more impressive figure of say 160rwkw at least!

ive raised the boost up after that to about 11-12 psi but it still doesnt feel like a jet..

138.8rwkw sounds a bit embarrasing. Do people talk rear wheel kw on here or mainly at the flywheel?

further down the track will be dump pipe, and power fc and tune.

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what about your cat? is it a highflow item or compliance item?

the cat and the standard dump pipe will be severly restricting the flow at that amount of boost.

Get a new dump pipe, and cat (if you dont have one already) and the car should push a shitload better when on boost.

also get a new highflow panel filter if you havent already, these basic steps will see you pushing some better figures.

And we all usually talk rear wheel kilowatts rwkw, its pretty hard to pull the engine and dyno it at the engine :O

i'l have to check my cat out. but ive got a newish looking 3inch system from the dump pipe and back.

I bought the car with a pod, so i dont have the standard airbox.

well i asked the guys that dynoed it how they got the flywheel figure, and they said it can be done by computer.. :O

so i guess its probably the dump pipe restricting me.

tho i could swear it nearly felt faster before i got the cooler and raised the boost :S

maybe just phsycological since there isnt that second stage boost kick any more

post your dyno chart it will help diagnose the problem... even if the dyno is reading low you should be making better power than that...

I make 200rwkw with stock cat and dump pipe so I'm not sure thats the best place to start... look to see if you have a problem before throwing parts at it IMO...

then a power fc or piggyback to lean out your mixtures and just make sure your pod isn't sucking hot air... then you should be right

Yes the good old first dyno... it was a shocker for me as well; but since then: lots of sweat, blood and $$$ to get a less embarassing number :)

I must say I was near tears when I saw my first dyno graph :O

hi mate, when u made 200rwkw was that also on "just under 10psi"? and was it in shoot out mode?

138 does seem low but when u said just under 10psi is that 9 or 8? cuz theres a fair bit of difference.

And id have to agree with the piggy back computer suggestion especailly when increasing boost!, already a turbo skyline runs rich, especally in the top end. this is an extreme measure the stock cpu takes to prevent pinging, but if u get better air to fuel ratios ur engine will have better combuistion and ull increase ur output by about 30rwkw

best of luck dude

post your dyno chart it will help diagnose the problem... even if the dyno is reading low you should be making better power than that...

I make 200rwkw with stock cat and dump pipe so I'm not sure thats the best place to start... look to see if you have a problem before throwing parts at it IMO...

then a power fc or piggyback to lean out your mixtures and just make sure your pod isn't sucking hot air... then you should be right

thanks for the replies.

It was practically 10psi, it did reach it at one stage but then bled off a touch which is meant to be ok.

I plan to make a box for my pod so it draws air thru a hole where the old intercooler piping came thru. Im sceptical on the result of this tho, as by the time the air goes through the turbo it gets so hot it needs to go via the intercooler anyway.

as i mentioned earlier i thought drivetrain power loss would only be 40kW max.. hehe not 60 :) depressing especialy when u see people posting these 190 - 220rwkw figures haha..

Is the general consensus that a piggy back computer with a tune will provide me with a Significant power increase for now, or do i need the dump pipe to make the most of it.

(spending $$$ on a dump pipe and powerfc at this stage is waay down the track at this stage unfortunately)

ok next thing i just thought of, compression test to see if there is any blow by past the rings, how many K's of the clock, the fuel Econ seems not to bad

I just had a look at the graph for some reason its been done in 3rd gear not 4th

well if you're running in shootout 6 it should read higher, most r33 with fmic & 10psi boost can easily make 180rwkw on the dyno chart.

something is definitely not right... are you sure:

1 your clutch is not slipping?

2 your tyres not slipping on the dyno roller?

3 your fuel pump is not dying? it happened to me and it confuses the ecu showing a/f is good but it's actually constantly retarding timing and i only reached no more than 150rwkw till i replaced the fuel pump.

4 in my experience with stock ecu, anything above 10psi boost will be a little bit hard for the stock ecu to manage, it'll get very confused, unless you have a freak one that handles 12psi ok. wait till u get powerfc before winding it up.

5. check other things that may contribute to the issue like your coil packs, fuel filter, plugs, and don't forget to check your base timing! had a mate who had weird pinging problem cos his base timing is way off.

I don't think its that bad a power figure. If you think about it stock would be about 130rwkw. You haven't finished the whole exhaust, intercooler doesn't really give more power by itself, 10psi + cooler probably too much airflow for stock ecu.

Mine at 10psi with with R34 cooler was goiong rich and retard. All depends on the setup but seems some seem to be able to handle more mods etc before stock ecu has a fit. I'm suprised people make 180rwkw without either piggyback or full ecu..my experience with the strock computer is that it is pretty cr*p

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