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Rolling Road Day


terribleturner

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My Dyno Plots from sunday...

 

Bit dissappointed as the car is

 

Overfuelling compared to before.

Also it isn't sustaining boost

Doesnt hit 1.2bar as it should

 

One the plus side...

 

Still sounds awesome

and I've got bags more of torque early on.

 

changes.....since last time...car now has an Apexi AVC-R and I got it tuned...and its got HKS iridiums as supposed to NGK Platinums before.

 

379BHP and adequate fueling to me looks good...should have plenty of happy miles in that car ;)

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379BHP and adequate fueling to me looks good...should have plenty of happy miles in that car ;)

 

True, considering that its barely hitting 1 bar, the results are good. Car certainly doesnt feel slow at all. However it is overfuelling and underboosting and it seems like the apexi's are setup correctly. So not quite sure what else could be responsible for the overfuelling (regarding the boost, perhaps there is a leak somewhere) ?

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True, considering that its barely hitting 1 bar, the results are good. Car certainly doesnt feel slow at all. However it is overfuelling and underboosting and it seems like the apexi's are setup correctly. So not quite sure what else could be responsible for the overfuelling (regarding the boost, perhaps there is a leak somewhere) ?

 

 

Could be a boost leak - when the ecu sees a certain voltage it just goes nuts and dumps in as much fuel as it can...it's not particularly accurate at this point as it's trying to "save" the engine.

 

If it's deffo supposed to be boosting higher, it wouldn't hurt to check all the little hoses for starters, the silicone stuff has a habit of tearing, personally I now use various diameter black hose from http://www.bsr-aerotek.com site...they also supply those coloured hex studs etc for the cam cover (i've got black ones now :) )

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Could be a boost leak - when the ecu sees a certain voltage it just goes nuts and dumps in as much fuel as it can...it's not particularly accurate at this point as it's trying to "save" the engine.

 

If it's deffo supposed to be boosting higher, it wouldn't hurt to check all the little hoses for starters, the silicone stuff has a habit of tearing, personally I now use various diameter black hose from http://www.bsr-aerotek.com site...they also supply those coloured hex studs etc for the cam cover (i've got black ones now :) )

 

Thx for that Alex. :D

 

Will check the hoses.

 

I've already ordered a new set of Hose Techniques from the states...should be here by the weekend.

 

one other interesting observation.

 

My apexi devices are reading different amounts of boost, SAFC only ever goes upto 0.84 kg/cm2 while the AVCR - has gone upto 1.05-1.15 kg/cm2 (despite being set @ 1.25).

 

Also the rpms that they read are sometimes out bu 20-50rpm.

 

And the AVCR speed reading is sometimes accurate, meaning when I am doing 30mph it reads around 50kmph, however so on the odd occasion it throws a fit and reads either the same as in mph OR even less....

 

I have confirmed that both are tapped into the same source.

 

why would this happen?

:faint:

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Thx for that Alex. :D

 

Will check the hoses.

 

I've already ordered a new set of Hose Techniques from the states...should be here by the weekend.

 

one other interesting observation.

 

My apexi devices are reading different amounts of boost, SAFC only ever goes upto 0.84 kg/cm2 while the AVCR - has gone upto 1.05-1.15 kg/cm2 (despite being set @ 1.25).

 

Also the rpms that they read are sometimes out bu 20-50rpm.

 

And the AVCR speed reading is sometimes accurate, meaning when I am doing 30mph it reads around 50kmph, however so on the odd occasion it throws a fit and reads either the same as in mph OR even less....

 

I have confirmed that both are tapped into the same source.

 

why would this happen?

:faint:

 

Bad connection possibly? Loose one?

 

If they are reading different pressure's then I would instantly be looking in the area where they T in to the car to the back of the units for boost leaks!!!

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Steve, I'm no expert, your AFR looks very lean to start off with and then rich????

 

Maybe Alex or Terry will be able to tell you if it's ok?

 

Cheers,

Ro

 

Steve's looks fine to me :) There is movement at 4-4500 but that's just to 12:1 which is safe enough

 

12.5:1 = Most power

11.7:1 = good power but safe.

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Guest Terry S
Mate, sounded like a high power Motorbike!:respekt:

 

 

 

Glad you heard it

 

Steve, I'm no expert, your AFR looks very lean to start off with and then rich????

 

Maybe Alex or Terry will be able to tell you if it's ok?

 

Cheers,

Ro

 

Not sure the AFR's on the dyno are 100% accurate TBH, my gauges are reading leaner.

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There is a facet to BPU cars with the fuelling acting like this depending on what boost you run. In a nutshell it is:

  • You run over 0.9bar of boost
  • You fit an FCD to stop fuel cut
  • The FCD holds the pressure signal at about 0.98bar
  • At this level of boost pressure the stock ECU runs 100% duty cycle
  • Therefore if you run 1.0, 1.1, or 1.2bar of boost, you still have the same amount of fuel going in (0.98bar of fuelling, 100% duty)
  • So you run rich at 1.0bar
  • So up the boost to 1.2bar and use up that extra fuel ;)

 

-Ian

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