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Do you get boost drop with your R34?  

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OK I've been looking through lots of threads comparing notes on all of the R34's that have started on their mod journey...almost everyone of them suffers from a marked boost drop in the second half of the rev range, more than you would typically expect from a similar modded R33.

One thing that has come up with my playing on my car is the TCS butterfly is pretty limp and I did see some gains from removing it.

Anyone out there actually got a dyno chart of an R34 with stable boost?

I must admit r34's cannot hold as much boost as the r33's do. and i speak from having both cars. i have both dynoed, and r33 seems to hold boost much stably unlike r34's which always decreases nearby redline even with a electronic boost controller. nonetheless, it still gives out alot of power.

Hi

Here is the dyno reads from my 34. its running a apexi turbo and it doesn't seem to lose much boost through out the rev range. hope this kinda help in what you are after.

Adam

post-39528-1207592271_thumb.jpg

post-39528-1207592284_thumb.jpg

Hey mate what engine management are you running just out of interest? We think we've found a look-up point in the factory ECU which down-regulates timing based on a few things, just means chipped ECU's are a pain to use unless you eliminate it.

What plug and play ECU options are available for the R34 Auto ?

I just picked up a 4 door and want to do some mods :-)

You can put a bikirom in, it's a daughter board that currently allows full adjustment of fuel and timing, this weekend we're emulating the factory ECU and unlocking every bit of it we can find in the tables, so basically full controll over everything and anything that it does (hoepfully find this crazy retarding map that's hiding in there and stopping my 250rwkw fun)

  • 4 months later...

digging this up Dan :P

just had my car remapped

mods

full 3" turbo back exhaust (BATMBL stainless split front/dump pipe, hi-flo cat (not the biggest one), HKS Super dragger catback)

Turbotech boost controller set at 12psi

FMIC (return flow one, from Just Jap)

Splitfire coilpacks (not really a mod i guess)

Blitz hi-flow panel filter

that's it i think, for the engine anyway :banana:

Boost drops at 4250rpm, to a low of 8.6psi i believe. Despite this, car made 180rwkw, and 190rwkw with the airbox cover removed :P, so if i can sort out the boost drop issues, tuner reckons the standard 200rwkw+ with these mods should be easy. Just want something in the 200's damn it!! :P

will put up dyno sheets

so i have lost around 3.5-4psi, with a the bc "set" at 12psi

I had my car tuned with a power fc and a profec b spec boost controller. I dont get a lot of boost drop (no more than 1-2 psi) tuned at 12psi.

I have only done the exhaust (3" turbo back), the intercooler is still standard along with everything else. Made 180rwkw.

I originally thought it was tuned to 10psi but later realised it was dropping to around 10 from 12 lol.

Im happy tho as it is well into its peak power by just before 5k and holds pretty well until redline.

  • 2 months later...

a bit of a dig but car is going in for a tune on thursday with new fuel pump so will post up dyno then.

atm car is running 220rwkw with the following mods

highflow turbo (16psi)

turbo back exhaust 3.5" all the way

FMIC

Z32 AFM

PFC

480cc injectors

highflow fuel rail

HKS cam gear

and a dieing fuel pump.

before injectors went in car was running 18psi and fuel pump was reasonably ok and that made 241rwkw so atm 220 is for a temp safe tune. once fuel pump is in looking at a safe daily tune of 260rwkw.

have a dyno graph here of the car when running 241rwkw and no boost drop at all. will post pic once silly scanner is working.

but ye will also post pic once car is dynoed on thursday

I've noticed the drop in boost your talking about. Mine seems to happen around 4500 to 5000rpm? i think. I will go for a squirt today. Im having a tomei fuel pump and turbosmart fuel reg installed tuesday and hopefully nistune done wednesday or thursday so I will post up dyno graphs. May be helpfully to have a less modded skyline with graphs to see if theres anything else that may be the cause of this.

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