R34Gtr Boost Question

[jescam]

Hi Guys.

I have been a member here for a few years, waiting for the time i would purchase a GTR.

I finally bought one yesterday, a R34GTR.

Its a beautiful car and i love it.

It has a HKS exhaust and pod filters fitted, and is apparently stock other than that.

The car also seems to have been well looked after and the motor has just been serviced and given a clean bill of health.

There is one thing i have noticed though......

I have had STI's in the past, and just came from an EVO 9, my GTR is totally different in it power delivery.

It is reaching around 1 bar boost high in the rev range, but compared to my previous turbocharged cars, it boosts up VERY slowly.

It is extremely 'gutless' down low.

I haven't been in any other stock GTR's so i have nothing to compare it to.

I have done numerous searches on both here and other forums, but i can't find any topic which matches what i want to know.

Is this SLOW boost build up normal?

After reading about the turbos, i don't want the car to have higher boost, I would just like it to build boost a LOT quicker.

Is there any way i can achieve this safely without getting a tune done?

I plan to get it tuned at a later stage, my bank account has to recover first!

Any help would be appreciated greatly.

[NISSAN GTR]

Depending how stock your engine is , it should not be GUTLESS down low , not like an EVO or STI at least- they are terrible down low , with your GTR boost should come on at pretty low = 3 K Revs and pull pretty hard all the way through to 7 and a half there abouts ,

6 cylinder RB26 with twin turbs is a near perfect design with only slight lag before 3k ,

I found the STI to be a total lag machine struggling to make it up steep driveways , there could be something wrong with your GTR posssibly .

I would invest in Apexi PFC

[iwanta34gtr]

Does it hesitate to come on boost? Does it miss? And then when it does come on boost does it come on hard?

Mine was doing the same thing, a few things to check

- Spark plugs

- Coil packs + lead

- Air leaks

- Intake manifold gasket + surrounding hoses

Where are you located? I can recommend a workshop to take it to for diagnosis.

[jescam]

My evo would've smashed it down low.

Although my Evo had exhaust,Cai and tune-216kw atws.

It doesn't miss, it comes on boost extremely linear and there is no real shove into the seat.

The engine idles smooth, and there are no backfires or flatspots.

I watched the boost guage on the display and it seems to stay at around 0.6 bar till around 5,000rpms and then ramps up to just over 1.1bar.

Again, watching the guage, the boost rises but slightly fluctuates up and down as it increases.

Hard to explain, you can't feel it, so its not rough as such.

Its smooth and linear.

When it revs higher, it does go quite quick, just the initial acceleration is quite 'doughy'.

The guy i got it off noticed the difference in how punchy my Evo was compared to it down low.

It just doesn't rev as quick as i think it should.

It still goes o.k, and normal people that aren't into turbo cars would probably think it goes o.k, but given my past experience,

i am dissapointed in it down low.

Being a twin turbo, i was expecting very little lag!?

I am located in Wollongong.

Again, thanks for any help.

[GTR-34A]

I have similar mods on mine, should not be as bad as described...

Did it just come Japan? Could be brought back to stock from modifications for compliance and require a decent tune?

[XKLABA]

It was serviced with a clean bill of heath, then a few things to look at, if the pods are HKS, change em quickly, check what cat it has and maybe change it to a good metal cat if it is the compliance still in there, then cam gears make a good difference, change the plugs to a 0.8 gap and reset the computer

[jescam]

It was apparently complied in 2008.

I am hoping a tune will 'wake' it up.

Is it possible to just flash the factory ecu, like for example a VE commodore or XR6T?

[Nee-san]

No it isn't.

the move from EVO and STI has probably exacerbated your problems as they usually drive around like a bag of dicks and then come on strong at high RPM.

Car should not perform as described though.

[jescam]

Wondering if i put in a Turbosmart Boost controller that i have from a previous car, instead of factory ecu controlled solenoid, if it would build up boost quicker?

I will check plug gaps, but from experience, wouldn't the wrong gap cause a miss?

So a reset of factory ecu may help cure the problem?

Thanks again.

[GTR-34A]

Once boost comes on should go all the way to max quickly, should not increase later at 5k rpm etc... If all runs smoothly could be a waste gate related issue?

[jescam]

Where are you located? I can recommend a workshop to take it to for diagnosis.

Where would you recommend?

[iwanta34gtr]

PM sent mate.

[Longz]

go get a power fc , boost controller and some pulley's ( not to mention a quick dyno tune )

I tell u right now the r34 gtr is slow as a crap stock.

once u awaken it a bit you will know why its king of the road

[jescam]

Sorry to dig up my old thread, but just thought i would give an update for anyone who was interested.

I have fitted a new front exhaust pipe, a set of yellow jackets, power FC and had it tuned.

It now puts out 254kw atw @ 1 Bar boost, and has totally transformed it into the car it should be.

I have now got the bug and want to go a bit further.

I have read quite a lot about other peoples mods, but to be honest, i am just getting confused.

I was thinking of replacing the turbos with N1 turbos with the steel wheels, so i can run more boost.

Can someone point me in the right direction, or direct me to a link, giving info on what my next mods should be, taking into account what i have done already.

I would like to get to around 300kw atw.

Thanks for any advice.

[kylieyeah]

Just lurk on the For sale thread until someone sells N1 turbos.

Otherwise can buy them brand new. The equivalents which everyone gets are the -7's by Garrett Turbos.

Although, if I was you I would order some -5's as I think you will always be wanting more power, where the -5's you can keep improving on quite a bit to pretty high numbers. Over 400awkw with the right mods.

-7 and -9 max out way before then, which I find it pointless to upgrade for someone like you as, I think you will have the urge to keep looking for more power. Also, people may say -5's are laggy, but with some cams, correct cam gear ratios and a good ecu and tuned well, it's great for the street and track.

[wedge_r34gtr]

Just lurk on the For sale thread until someone sells N1 turbos.

Otherwise can buy them brand new. The equivalents which everyone gets are the -7's by Garrett Turbos.

Although, if I was you I would order some -5's as I think you will always be wanting more power, where the -5's you can keep improving on quite a bit to pretty high numbers. Over 400awkw with the right mods.

-7 and -9 max out way before then, which I find it pointless to upgrade for someone like you as, I think you will have the urge to keep looking for more power. Also, people may say -5's are laggy, but with some cams, correct cam gear ratios and a good ecu and tuned well, it's great for the street and track.

This^^^. but if you buy 2nd hand n1 turbos, make sure they are ball bearing.

[jescam]

So if i was to purchase a pair of N1 turbos, what else would need to be modified to produce around 300kw atw?

Would i need to change the fuel set up or cam pulleys or?

I don't want to spend any more money than i have to at this stage.

Thanks.

Edited November 17, 2012 by jescam

[wedge_r34gtr]

Definatly an ECU.... possibly injectors, MAFs & a EBC.

cams/gears and fuel set-up will be fine

[Hadouken]

You are going to have to upgrade your fuel system and front pipe if it is stock.

Also, there is no point getting -5's if you dont plan on rebuilding the engine. 300kw is a much safer figure for the rb26's

[(OO)SKYLINE(OO)]

You are going to have to upgrade your fuel system and front pipe if it is stock.

Also, there is no point getting -5's if you dont plan on rebuilding the engine. 300kw is a much safer figure for the rb26's

This!

And preferably with a 2.8lt kit or you will be back with a slight lag, instead of the response with -7 / -9's.