Jump to content
SAU Community

Recommended Posts

Hay guys, had my gtr tuned a while back and it was lacking on power something fierce.... it running 350 hp at all four on 15psi.... it built and all the rest... ive changed the exhaust twice and seem to not change anything.... the only thing i can think is the exhaust is very quiet for a 3.5 inch hks..... it got a high flow cat. but i cant seem to find the problem.....maybe the turbo???? maybe the manifold?? maybe the exhorst????

any ideas would be great....

thanks

ps would like it to spool bout 1000rpm earlier, any ideas also would be great....

oh yeah the turbo comes on about 5200 rpm full boost... i think thats a little late but not to sure.....

Link to comment
https://www.sau.com.au/forums/topic/317522-lack-of-power/
Share on other sites

  • Replies 49
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Posted Images

Ok first thing you gotta ask yourself, does it make much more power on much more boost. If the answer is no, you know you have a problem.

You said you changed the exhaust twice, as in the catback? That usually aint going to do shit as the exhaust restriction is usually due to a collapsing cat. What "high flow" cat is in there?

What does the power graph look like? What are the turbo specs? What ECU?

Also if it was tuned a while ago and made that power on 15psi, what did the tuner say? Why did he leave it like that and give it back to you.

Need more info man.

Edited by PM-R33
Link to comment
https://www.sau.com.au/forums/topic/317522-lack-of-power/#findComment-5190864
Share on other sites

sorry guys. its got- stock cams. garret t04z .70 and .84. jap manifold. tial copy 44 mm gate. 3 inch dump. 3.5 inch magna flow cat brand new. 3.5 inch Hks exhaust. 044 pump in tank. 780cc injectors . vipec comp. tuned by godzilla motor sport. made 280Hp on 11psi. 350Hp on 15psi. 380Hp on 17 psi. my exhaust is really quiet. my mate has same exhaust and can't even tell my car is on when he is sitting next 2 me at the lights. we tried swaping exhaust and taking cat Out no difference yet. but haven't checked on dyno.

Link to comment
https://www.sau.com.au/forums/topic/317522-lack-of-power/#findComment-5191181
Share on other sites

A feller I know recently was playing with an RB26 in a VL , it had a 6Boost manifold with a 44mm TiAL and a GT3582R with the 1.06 AR turbine housing + questionable 3" exhaust .

He felt he made significant gains by having a 3.5" exhaust all the way through , just about everything I've seen indicates that the exhaust needs to be BIG right behind the turbo and if I was you I'd strongly consider having a 3.5" if not larger dump pipe .

That feller mentioned above also found that the 44mm waste gate wasn't coping and boost crept upwards , had a different fitting welded on for a 50mm Turbosmart gate and that solved the creep problem .

From memory he had a 100 CEL cat fitted , don't remember which brand .

For the record does the turbo and manifold use a T3 or the larger T4 sized mounting flange ?

A .

Link to comment
https://www.sau.com.au/forums/topic/317522-lack-of-power/#findComment-5191275
Share on other sites

  discopotato03 said:
A feller I know recently was playing with an RB26 in a VL , it had a 6Boost manifold with a 44mm TiAL and a GT3582R with the 1.06 AR turbine housing + questionable 3" exhaust .

He felt he made significant gains by having a 3.5" exhaust all the way through , just about everything I've seen indicates that the exhaust needs to be BIG right behind the turbo and if I was you I'd strongly consider having a 3.5" if not larger dump pipe .

That feller mentioned above also found that the 44mm waste gate wasn't coping and boost crept upwards , had a different fitting welded on for a 50mm Turbosmart gate and that solved the creep problem .

From memory he had a 100 CEL cat fitted , don't remember which brand .

For the record does the turbo and manifold use a T3 or the larger T4 sized mounting flange ?

A .

+1 a 3" dump pipe behind a T04Z is criminal. 3.5" at an absolute minimum.

The other thing I would try is running it on the dyno without a cat, so just using the dump pipe.

Link to comment
https://www.sau.com.au/forums/topic/317522-lack-of-power/#findComment-5191454
Share on other sites

Power and response see about right for your combo, This GTR only made 369hp @ 15 psi and 461hp @ 17 psi the T04z is a cop on a std rb26 until 20-24psi (decnt manifolds do help a bit).

The same setup then made well over 500awhp @ 22psi. Your boost response seems about right too for your setup.

post-34927-1271809409_thumb.jpg

Link to comment
https://www.sau.com.au/forums/topic/317522-lack-of-power/#findComment-5191485
Share on other sites

Just for shits and giggles check out the gt2860-5 @15psi versus To4Z @15 psi, i wont post the -7's or -9's as it is even better again.

The T04z needs minimum 20psi to wake up and a redline of 9000rpm, not ideal for a stocker.

post-34927-1271809998_thumb.jpg

Link to comment
https://www.sau.com.au/forums/topic/317522-lack-of-power/#findComment-5191498
Share on other sites

  STATUS said:
Just for shits and giggles check out the gt2860-5 @15psi versus To4Z @15 psi, i wont post the -7's or -9's as it is even better again.

The T04z needs minimum 20psi to wake up and a redline of 9000rpm, not ideal for a stocker.

interesting... r32-gts t04z was making 520rwhp on 16psi and mine made over 500 on 17psi

both were also making loads more torque between 4000-5000rpm compared with the graph you posted... something wrong with the setup?

Link to comment
https://www.sau.com.au/forums/topic/317522-lack-of-power/#findComment-5192197
Share on other sites

well im seeming to agree with you guys about the dump, but have seen the same turbo come on harder alot earlier with the same set up. and make more power at 18psi...... there is a gtr at godzilla motorsport that runs the same turbo and has made 540hp on 18psi , the only differance is a set of cams, and a sub zero manifold, and a 4" dump + cat back.....

i am not running cam gears yet.. the are sitting in a box under my bed atm...... as cams would be good also - any sugestions????

the engine is rather fresh and godzilla motor sport didnt want to push it to hard......

as for response id like to drop it buy about 1000 to 1500 rpm...... so im thinking :cams : cam gears: 3.75" dump: sub zero manifold : hpc coating:

any thing else would be great......

ps i ran a set of standard turbos with same engine and it ran 330 kw on 19 psi..... and came on at 2500 rpm... would it be cheaper putting some steel wheels on these and boosting them up????

Link to comment
https://www.sau.com.au/forums/topic/317522-lack-of-power/#findComment-5192604
Share on other sites

Yeah, they said to put cam gears in it, change the exhorst ( remove the middle muffler ) change the intake pipe (pod set up) and maybe a cold air box...

out of that the exhaust has been change to a hks 3.75 inch, pod has been moved into the guard with a cold air box.....

the only thing im waiting for is cam gears to go on , i just dont want to put cam gears on it and them 6 months later put cams in... trying to figure what to get for it.,.....

sorry it was 330 hp.... was looking at the wrong sheet...

Link to comment
https://www.sau.com.au/forums/topic/317522-lack-of-power/#findComment-5192642
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • You just need to remove the compressor housing, not the entire turbo. I would not be drilling and tapping anything with the housing still on anyways. 
    • So, I put my boat on a boat. First of all, I'm going to come out and say it. Why is Tasmania not considered a holy goal, an apex that all road-legal modified cars go to, to experience? This place is an absolute wonderland of titanic proportions. If people are already getting club runs for once in a lifetime 30 person cruises to Tassy then I've never seemed to see it. It is like someone replaced the entire place with an idyllic wonderland for cars, and all of the people living there with paid actors who are kind, humble, and friendly. Dear god. After doing a lap of almost all of the place I've found that it's a great way to find out all of the little things that the car isn't doing quite right and a great way to figure it all out. All in all, I drove for 4 hours a day for a week and nothing broke. I didn't even need to open the engine bay. This is by all means a great success, but it has left me with a list of things to potentially address. I also now have a 3D printed wheel fitment tool which annoyingly hasn't got any threads in it to actually assemble it. I might be able to tape it together to check the sizing I actually want to use, but it'll likely involving pulling the shocks out to properly measure travel at least at the front, and probably raise the car while I'm at it, at least in the rear. I scraped on quite a few things and I'm not sure how else to go about it. I was taking anything with a bump at what felt like 89 degree angles. And address those 10 other tasks. And wash the car. God damn it is dirty. And somehow, the weather was perfect the entire time - And because I was on the top of Mt Wellington it turns out it was very much about to freeze up there. I did something I typically never do and took some photos up there in what must have been -10 and the foggy felt like suspended ice, rather than mere fog. If you own a car in Australia, you owe it to yourself to do it.
    • Damn that was hilarious, and a bit embarrassing for skylines in general 馃槀 vintage car life ey. That R33 really stomped. Pretty entertaining stuff
    • Hi, I have a r32 gtr transmission. Does any of you guys have an idea how much power it will hold with the billet center plate and stock gearset? At what power level and use did yours brake with or without billet plate? Thanks, Oystein Lovik
    • Saw this replica police car based on a Mitsubishi Starion XX parked next to a 'police box' (it's literally a box) in Hirohata, Himeji City in Hyogo prefecture the other day. It's owned by Morii-san who is a local Mitsubishi Starion enthusiast. According to a local radio station blog post, he always wanted to make a police car himself based on ones he saw in his favourite Manga comics.  As it's illegal to modify a car to look like a police car and drive on the road, Morii-san tried many times to get permission from Aboshi police station headquarters nearby. They refused initially by after they got tired of that they granted him permission. However, the car can only be displayed on private property and obviously can't be registered as long as the police livery is present. The car was completed at a cost of 1.5 million yen (US$ 10,000) in addition to the car cost. A location was chosen outside Hirohata Police box where the car can easily been seen from the street. Morii-san has two other Starion road cars, both widebody GSR-VRs.
  • Create New...