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Did dyno run a few weeks ago and now wondering what it means and how much more can be gained. Setup is fairly stock, 3" turbo back, 12psi, superspark coils.

My limited knowledge of AFR's tells me this gets fairly rich, and by getting the WOT AFR closer to 12.5-13.2 I could squeeze more power from it? Can anyone estimate how much? And what would be the best method, haltech, safc, pfc (nothing wrong with future proofing :(

Only have the boost/afr part pic of the sheet with me at work, if the whole sheet is required then I'll upload once home. Also, what causes the 10. flat spot at the end of the run, injectors maxed/ecu?

post-63773-1257477377_thumb.jpg

Thanks!

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I wouldn't really go leaner than 12:1 personally, the high 12/low 13 AFRs are ratios suited to NA cars... turbo cars like a fatter mixture but yes, the air fuel ratios you have are terrible. I'd consider checking to make sure you don't have an air leak somewhere.

here in nz we get 220-240kw on 12psi out of stock rb25det with front mount and 3" exhuast and a link ecu on dynapack hub dynos

standard injectors are maxed about 230kw although we have got 237kw on stock injectors.

safe and ideal af ratio for turbo car is between 11.6 and 12. 11.8 is the aim

getting an ecu that runs with out an afm is always good. depends on what your tuners in your area are familar with.

220-240rwkw out of a stock turbo is stupidly innacurate. your dyno is just plain wrong if its spitting out figures like that with a stock turbo, especially with a stock ecu

as said 12:1 is ideal under full load for a turbo car

220-240rwkw out of a stock turbo is stupidly innacurate. your dyno is just plain wrong if its spitting out figures like that with a stock turbo, especially with a stock ecu

as said 12:1 is ideal under full load for a turbo car

+1

From all what I have read, 200rwkw is about the max you can make with just 'basic mods' for the RB25DET. Moving beyond 200rwkw most likely need a aftermarket turbo or high flowed stock one & run more boost & also require the supporting mods.

For reference, my auto 33 made ~180rwkw with basic mods (3" turbo back exhuast, R34GTT SMIC, bleed valve +10psi setting & SAFC II)

220-240rwkw out of a stock turbo is stupidly innacurate. your dyno is just plain wrong if its spitting out figures like that with a stock turbo, especially with a stock ecu

as said 12:1 is ideal under full load for a turbo car

A hub dyno will always read higher KW figures over a roller dyno.

Their figures are quite accurate for the dynos they're being measured on. You can't compare, and this is why dynos are BULLSHIT.

if you read my post i had said Link ecu(i think its called vipec over there)

dynapack hub dynos are the most repeatable dynos out there, hence why nascars etc are tuned on them, as there is no crap like tyre slip etc

only thing they lack is a shootout mode for comparing against other dynos.

ie if you do 2 runs in a row. with out changing anything the runs will be within .2% of each other.

most people don't push stock turbos above 220kw.

here is the 2 that im talking about on this page. the first one is r34 neo rb25det(VVT isnt working), the 2nd is r33 rb25det. both with links, front mount and exhuast

http://www.skylinesdownunder.com/forums/sh...8244&page=2

my r33 with stock turbo, front mount, 3" exhuast made 220kw on 10psi on a basic road tune with a LINK ecu.

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