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S2 Rb25Det Falls Into A Black Hole At 6000Rpm

Ad's

By Ad's,
in Engines & Forced Induction

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Ad's Mentor

Ad's

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Posted (edited)

Hey guys

I have installed a S2 RB25DET into my HR31 coupe over the last few months i regoed it over a month ago and all is good, pulls nice and seems to drive like it should. I gave it to a local tuner to put her on the dyno and run it up to see if there is any problems turns out after 9 power runs everytime at 6000rpm and making 140rwkw it drops off, he said they usally drop off a little bit but then pick up and goes to the red line as mine doesn't.

Fuel is rich and it isn't leaning out.

No vac leaks or boost leaks.

The motor isn't breathing oil.

Timing is right.

AFM seems to be in good working order.

CAS seems to be in good working order.

He seemed to think the timing belt had jumped teeth and told me to check it, i thought if the belt had jumped over it would be running bad all the time and not just at 6000rpm. So i checked the timing belt and all the marks line up.

I went over my wiring and from what i have wired it up from it's correct.

The CAS isn't off centre as the timing is back to 15 degrees at roughly 850 rpm on idle.

New splitfire coilpacks less than 1500 km old.

New NGK copper plugs pre gapped to .8 less than 1500km old.

Before the motor went in it had new oil and filter, fuel filter, coolant and flush, water pump, timing belt and a boshi 040 installed.

Im taking the car back on Friday to have a some more work done with re run with a mates S2 computer, as i have a mate that works at the tuners shop and he reckons it might be ecu related.

The motor is pretty much stock apart from:

FMIC

Greddy profic type II boost controller (witch is off currently)

Boshi 040

3 inch exhaust with a centure muffler and rear muffler

Splitfires

Im thinking of getting a tune done with a power fc but im pretty sure my problem will still be there even with the new computer and tune.

As you can see im all out of ideas.

Any ideas or help will be great!

Cheers

Adam

Edited by Ad's
The Mafia Grand Master

The Mafia

Posted
Posted

dude.... 140rwkw and beyond is the rich and retard maps in the factory ECU.

TUrn your boost up and I bet it hits this hole a whole lot earlier.

Get a tunable ECU, its a known fact that the factory ECU is useless for anything above stock power.

You are wasting your money trying to "fix" the factory ECU.

Powerfc...

Ad's Mentor

Ad's

Posted
  • Author
Posted

Boost controller got turned off as it was only making it run worse! And its still off currently! I will be looking at a power fc soon when i don't have a lack of money.

The VCT is working as it clicks and my mate pointed it out when it was in there!

Thanks

Ad's Mentor

Ad's

Posted
  • Author
Posted

Apparently its my air flow meter in the cooler piping! It's going back in a week or so when i have moved it back and seeing it it changes anything!

islade : I borrowed a mates manual computer and it didn't make a difference.

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