Restriction In The Exhaust

[hypergear]

A guy with PT5558 on R34 neo made 372rwkw @26psi, the only difference- he had e85, top mount ex manifold and ffp. Mick O made 335kw on stock manifold btw...

^^

In this case the OP6 high flow made more power on less boobst

Like mentioned earlier, higher octane fuel will allow you to run timing that is closer to the optimum degree.

Or you can also enlarge the exhaust side turbine wheel that has similar effect to an larger rear housing. This case a larger housing would be the cheaper way to get more power.

[rondofj]

What I was tryin to say is I dont think the turbo is a limitation itself since 372kw and 360kw was made with the same turbo on a neo and an sr (both e85) respectively, as posted by the guy above. And mick O did 335kw on stock mani, so have many others gone over 300 on stock mani. Just my opinion

[rondofj]

One thing however, this is a reasonably responsive turbo - 200kw@4000rpms and 110kw@3000rpms -- the rear oval muffler with the 2.75" guts is still not removed though.

[Ben C34]

You still have your nistuned ecu right?

Put it back in and see what happens.

[rondofj]

Yeh, but that's tuned for 18psi and my car now runs on 22psi as set from the T boost controller I would think. Putting that ecu on, once it goes past 18psi could result in a BANG aye.. lol

[hypergear]

What I was tryin to say is I dont think the turbo is a limitation itself since 372kw and 360kw was made with the same turbo on a neo and an sr (both e85) respectively, as posted by the guy above. And mick O did 335kw on stock mani, so have many others gone over 300 on stock mani. Just my opinion

Well SR20det in .63 is equivalent to an RB on something like a .84. That R34 has much better hot side setup then yours and on E85.

Like mentioned earlier, Tuning P98 with a tinny rear housing will need to have detonation in mind, in which you will have to back off timing from the optimum ignition angle to avoid pinning. You have less of this issue tuning E85 fuel, that allows you to fire spark closer or at the crank angle for optimum engine output.

Or you can just run E85, which should boost up 40KWs in power getting you over the 300rwkws mark on the same boost level.

Edit:

Add in one more piece of information: Garrett GT30's turbine is in 60in / 55ex. The tip height and exducer area determines the total capacity of discharging, so technically this turbine does not have much better capacity to a GT30 turbine.

[rondofj]

How much more power do you think a 0.82 housing will give me? 10kw? Not worth the removal/fabrication of gate/ labor again I think.

Yavuz suggested cams and also an ebc to keep boost up. Any guesses as to how much I will gain with an ebc holding boost well. 280rwkw was made on 18psi not 22.

[Manuel Kasko]

Sounds like the cas issues Tony was having in his 34gtt. Why randomly pick the exhaust to be at fault without testing it?

[rondofj]

If it was CAS, a tuner like Yavuz or even Mark should have been able to pick it up straight away and inform me? Or tested a different one. Well changing the exhaust definitely did feel a noticeable gain on the road from driving feel (without touch up tune), after the touch up tune it felt a lot lighter and torqueyer down low, so definitely the exhaust had some restriction. One strange thing now 100km/h in 5th is @2600rpms, before exhaust/touch up tune 100km/h was at 3000rpms...

[hy_rpm]

Cams in a rb as tested by Tao only gain very little but shift power band higher

Where as you where making 200kw by 4000rpm it will proberly be 150kw and full boost will be later as well so won't be good for street and be felt at the track only

You should have ran your nistune tuned by Jem with 287kw on Unigroup dyno and seen where it was at to compare but does it feel quicker than before or the same ?

[Ben C34]

Cams in a rb as tested by Tao only gain very little but shift power band higher

Where as you where making 200kw by 4000rpm it will proberly be 150kw and full boost will be later as well so won't be good for street and be felt at the track only

You should have ran your nistune tuned by Jem with 287kw on Unigroup dyno and seen where it was at to compare but does it feel quicker than before or the same ?

You can't establish anything from that test, as it lost vct. And you are guessing wildly.

There are results of cams picking up power everywhere, for example Matt from Nistune's r34.

[rondofj]

It doesn't feel quicker, much less the same, maybe pulls a wee bit harder in 3rd/4th and a lot better under 3000rpms - more light/torquey down low, this is the area that wasn't tuned well with Nistune. Also cold starts and idle is much smoother and like factory now, before was rough and I had to crank twice/push gas pedal to start.

[Ben C34]

. One strange thing now 100km/h in 5th is @2600rpms, before exhaust/touch up tune 100km/h was at 3000rpms...

That makes no sense.

Diff ratio is the same. Revs the same.

[Ben C34]

It doesn't feel quicker, much less the same, maybe pulls a wee bit harder in 3rd/4th and a lot better under 3000rpms - more light/torquey down low, this is the area that wasn't tuned well with Nistune. Also cold starts and idle is much smoother and like factory now, before was rough and I had to crank twice/push gas pedal to start.

That's a shame that your Nistune wasn't tuned correctly. Don't blame the ecu.

It would have to be the easiest ecu to get cold start and idling nice with.

[rondofj]

That makes no sense.

Diff ratio is the same. Revs the same.

More revs needed before for same power/speed looks like it? Remember its a freer exhaust now, so boosts quicker and makes more power at least 400rpms earlier. And more timing been added across the rpm scale. And yeh they didn't tune the Nistune correctly, not even after the second time.

[gtr jet]

More revs needed before for same power/speed looks like it? Remember its a freer exhaust now, so boosts quicker and makes more power at least 400rpms earlier. And more timing been added across the rpm scale. And yeh they didn't tune the Nistune correctly, not even after the second time.

That doesn't make any sense. If you had 1000hp it should still sit on the same rpm at 100km/h.

[GTSBoy]

One strange thing now 100km/h in 5th is @2600rpms, before exhaust/touch up tune 100km/h was at 3000rpms...

Seriously? This cannot be true. Think about it.

[gtr jet]

Did you swap your standard wheels over for 22's?

[Ben C34]

You already had a perfectly good ecu.

It's a shame you didn't just sort out exhaust then get someone else to tune the Nistune.

[zebra]

Pays for tune

Gets new diff centre