Jump to content
SAU Community

Recommended Posts

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!

Link to comment
https://www.sau.com.au/forums/topic/295126-yet-another-dyno-sheet-thread/
Share on other sites

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.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • It makes you wonder, all these people starting to make a billet replacement head, I wonder if any have thought about trying to adapt tech from newer engines into them. You're already at the full design stage to make a billet head... Why not really spice it up and had some more modern tech into the mix too...
    • Connect all the plumbing up properly. The actual worst part about having the turbo unable to actually build boost, is you can and likely would over soon the turbo if you drove the car (free rev while stationary isnt likely to manage it).   If you do have an air leak as Duncan suggested, you'll have a bad time as the AFM will be saying different to reality.   As you have had the engine out, I'd go over all electrical connections again. If you have a consult cable, plug it in, and see what the ECU thinks is going on. Did you touch the timing belt? If so, double check your timing on the gears is correct AND put a timing light on it while it's idling and see what ignition setting you have. Is the AFM you've installed the one that was in the car previously? You said you replaced seals, what seals exactly? What have you had apart?   From memory when I had my RB25DET with factory throttle, there was two plugs the TPS plug on the loom could go to. One would leave the car running like shit, the other made it work, I think one plug on the TPS area was for something else (an option). It's too many years since I saw that part of the loom to remember properly though.   Is the car idling smooth (as smooth as an RB can)? Does it smell fuelled up?   I have a feeling either timing in timing belt is off, or a sensor isn't right.
    • Theres still skid pan and motokhana days up in QLD at least that are $100 or less. The ones that are ran as "driver training" less so, they're expensive, but just normal skid pan days like SAU ran are still low cost. And thats one of the places I learned to be a lariken, purely by asking for passenger rides, and how people were doing crazy things. Reese gave me plenty of pointers back in the day for skid pan! And yes Duncan, I will never forget your pointers for track work. Especially after Neil got out saying "I am NEVER getting in the car with him again!" 😛
    • 49719 is the cooler loop. Right at the front, LHS of that diagram. Return line from rack (LP side) goes to cooler loop on RHS front of car, then back under engine and returns to bottom of tank. 49717M is feed from tank to pump. HP line out of pump is thick rubber, followed by the hard line that runs down to crossmember and runs in parallel (but opposite flow direction) to the LP return line. Nothing goes anywhere near the firewall or interior of car. The closest they get to that is the connections on the rack.
    • Thanks, plan is to drain all fluid tomorrow and do smoke test to find out the leak.   Appreciate your help and want to understand how the system work. So cooling is achieved by the long loop not any rad? The diagram seems to suggest it connects to somewhere inside the cabin and I thought that is a cooler inside firewall. If you look at the diagram it seems to show it connects to something inside firewall. I tried chasing it but not easy unless I take loads off   i am confident pump is good as fluid goes in and it gets soft( steering) but as soon as I turn engine off , loads of bubble come to surface and overflow. When engine is on , fluid level is below minimum but when off it shoots off and thinking it is sucking air in. I suspect aluminium pipe may have a crack line or whole   smoke test with no fluid should be a good start and if needed will remove the pump   In addition, the one going under the engine bay is high pressure line and one directly connecting from pump to resorvoir is return/ low pressure?   finally I searched and suggestion is to use dexron 2 but that is discontinued so bought dexron 3 as all research suggest it is compatible and shouldn’t cause any issues/ blow seals. I bought two liter of dexron 3 motul atf
×
×
  • Create New...