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hi

i've got a bit of a 'dip' happening between 4000-5000rpm in the power curve.. seen here:

www.googz.comtempgug25t-161.jpg

i know a few posts have been made like this in the past but i thought id post mine anyway as the graph might give more away... i have a stock skyline (automatic converted to manual by hills motorsport).. it was running ~8.5psi boost but other than that is completely stock car.

would a s-afc fix the dip in the power curve ? i know something like powerfc would do nicely but i was hoping to avoid that cost if possible..... im looking for something to smoothen it out .. rather then peak figure...

thanks in advance for your input :D

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https://www.sau.com.au/forums/topic/6510-check-out-this-dyno-result-any-ideas/
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Hi, i was also at the Dyno runs on Saturday - great day.

I had the Red Series I R33 GTS-T - 192kw@12psi

http://skylines.pnc.com.au/ben.html

I don't know anything about these things but if i was you i'd be getting a nice air filter and a cat-back exhaust system.

An S-AFC would definitely smooth it out, however the Power FC is still preferable if you have the money.

But if you're a poor bastard like me, an S-AFC is good enough to tide you over until you can afford the Power FC. Here's a printout of my dyno run before and after the S-AFC tune. I had a similar flat spot at around 4000-6000rpm and it's now gone.

Originally posted by JimX

An S-AFC would definitely smooth it out, however the Power FC is still preferable if you have the money.

But if you're a poor bastard like me, an S-AFC is good enough to tide you over until you can afford the Power FC. Here's a printout of my dyno run before and after the S-AFC tune. I had a similar flat spot at around 4000-6000rpm and it's now gone.

interesting :D

what mods have you got there ?

Fmic, T04 turbo, EBC, cold air box with pod, 3.5" exhaust from front pipe back. The dump pipe is the next thing on the list to do, was going to do it in a couple of weeks but can't afford it till next year now :D

Originally posted by GooGZ

jezus! that is a difference...

well i just saw a the dyno of ROBOs series 2 skyline.. he has standard zorst like me but he has a fmic... and he has no midrange drop.. and no electronic tuning as yet.. hmmm...

fmic or safc... ?

both!!:D

Originally posted by Mark0

JimX how much power have you got there ?? dod that say 166rwkw ?

And thats in a R33 with a t04

I was going to reply too, but with a little less tact :D

  • 8 months later...

My dyno looked very similar to tyours unti I installed a PFC - then what a difference. Before i could feel it drop off under acceleration, but now it pulls strong all the way. I think this dip is programmed into the original ECU to help it meet emission standards.

I would suggest installing a PFC,or at the least a S-AFC.

I am not disapointed in the PFC and the potential to go further in the future is always there, whilst the S-AFC is a good fix but if you want to continue further eventially you are gonig to have to change the ECU anyway.

does anyone have a definitely answer to this problem .. i know i have this problem as i can feel it .. and my car is an auto .. 3rd is really shit ... can feel the loss in power ... with so much pepole having this "problem" it does seem that it is programmed in factory ...

googz, one more thing i could recommend is possibly hi-flowing the turbo...I've got a T03/T04 hybrid turbo which has been hi-flowed by the previous owner :P, n I've made 270bhp at 15psi after installing an S-AFC...with no fmic. Once i get one on, my tuner expects 300+ bhp, and for me to do a 12.5 run at willowbank...the bastard!

anyway, the S-AFC gave me 66 more hp, so i would say get that first, then an fmic, then see what u can do to hi-flow ur turbo...if u're looking for crazy horsepower and a clean torque curve of course. :)

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