R34 Gtt Losing Power On Dyno

[Nachos]

Hey everyone,

I did a search and couldnt really seem to find anything, thus why i started this thread.

I have a R34 Gtt with the following mods

Blitz front mount

Nismo/Blitz turbo back exhaust, (stock cat)

Gapped dot 7 plugs, with splitfire coilpacks

Eboost 2

Everything else is stock, so the other day i went to go get it tuned. Now to the problem i need help with. We were trying to tune the car and at around 4500 to 5500 rpm the car would drop off power by up to 40 hp. and the after 5500 it would kick back up.

So the curve was smooth upwards, slopped downwards b/w 4.5 and 5.5 rpm and den kick back up. But when we were tuning on ~10 pounds this would not happen, only if we boosted more than 40 duty. i ended up making 240 hp (~180 kws) to the wheels

Has anyone had this problem before? is it because i dont have a nistune and must fix something to get the smooth curve through the computer? my tuner thinks it might have something to do with the tcs (double throttle body) not letting air in??? i read up on some dyno figures on SAU and people were

running 210 kws at 13 psi with a nistune... so im assuming the power delivery was smooth??? as well that they are still running their stock throttle body!!! I think its the nistune...

Any suggestions??

Thanks for reading!!!

Michel

[Bsa]

Did you drop tge exhaust

[Moodles2]

Define "tuning", are you doing it with the stock ECU?

If so I'm guessing you're adjusting the CAS? then that is laughable and I wouldn't be going back to that workshop.

[Nachos]

Drop the exhaust??? Don't get what u mean but no.

Yeh with the stock ecu so just mucking around with the eboost, duty and gate pressure etc...

[Nachos]

What's CAS?

[TTT]

Drop exhaust = unbolt the cat and the rest of the system so it just leaves the dump and front pipes - this tests if the cat convertor is blocked.

Cas = Crank Angle Sensor

you already answered your own question.

you need a tunable ecu

[Bsa]

Get a nistune or other programable ecu replace the cat as it will cause restriction (lower pontertial power) and go again

[Nachos]

Okay I see, thanks for the help guys... I'll get that done... :-)

[SS8_Gohan]

If so I'm guessing you're adjusting the CAS? then that is laughable and I wouldn't be going back to that workshop.

this

but as for what you're talking about, it's actually very common to have that 'step' in the power curve. Get a Nistune, and a decent tuner will be able to sort it out easy.

Depending on the mods you have planned, consider getting a Link G4 as well. Where are you located?

[DVS JEZ]

Also checkif the stock intake pipe from the airfilter to turbo isn't sucking shut when power dips

[Nachos]

Okay! Thanks for the replies, I'm from Sydney... Western suburbs...

[TTT]

next mod should be comprehensive insurance then.

[Bsa]

Haha

[Nachos]

Hahaha, that was the first mod

next mod should be comprehensive insurance then.