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Well...peak power isn't the aim...area under the curve is the aim...and with consistant boost pressure i'd get more area...

The turbine housing can do it...proven here in this thread...http://www.skylinesaustralia.com/forums/Gt....html&st=20

So the issue is more likely to lie with my setup...and not my turbo...which some people seem to be wishing for... :)

Fair enough... well in that case I don't know what to suggest lol

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Well...peak power isn't the aim...area under the curve is the aim...and with consistant boost pressure i'd get more area...

The turbine housing can do it...proven here in this thread...http://www.skylinesaustralia.com/forums/Gt....html&st=20

So the issue is more likely to lie with my setup...and not my turbo...which some people seem to be wishing for... :)

Why dont you get one of the large can actuators in that thread you linked?

Why dont you get one of the large can actuators in that thread you linked?

If you read my first post...you will see that i do already have that large can actuator...and i also mentioned that boost response curves were pretty similar between the old and new ones...

Seriously I can really make that work and hold it at what ever "high" settings you want it to set it. even at 24psi as long as the turbo it self can take it (assume engine's won't have issues).

Ya...i believe you...if the sun rose in the west and set in the north...

I've run 30psi on my turbo accidentally before...it can do it...which proves the turbo isn't the issue...not converting me to a believer...sorry...

Ya...i believe you...if the sun rose in the west and set in the north...

I've run 30psi on my turbo accidentally before...it can do it...which proves the turbo isn't the issue...not converting me to a believer...sorry...

lol well, then carry on and find your own solution. As I've already found mine.

Holding 20psi with a stock R33 21U turbine housing:

http://www.digi-hardware.com/images/dynosh...rwkwhfboost.jpg

Limpus - hitting 30psi and holding/flowing 30psi efficiently are different, there COULD be something else causing it but hard to tell. I've asked before, how much power is it making, or has it even been on the dyno? You would have a good idea from power figure... or what the tuner says regarding what he/she had to do during the tune of how much more the turbo has to give.

Its also not been equal that you are running on a "NZ dyno" with all the enchantments for better response. This also made you the most responsive 3076R .82 int gate through out Australia. Far better then some with cam gears and external gates. Run that on Status dyno and see what happens.

I run mine on a Dynapack (NZ dyno - same as what Status use), stock manifolds, a big can actuator and an AVC-R - there is nothing overly exotic there, I have just gone through everything and made sure each bit is doing its part properly. No magic, and it could still be better. But anyway I wasn't trying to do this, lets say the Hypergear turbos are all good (they seem to be) so this stays on topic.

I think its just a inherent problem with internal gate turbos...

I have seen large internal gate turbos from different manufacturers not hold boost including (but not limited to) HKS, Apexi, Garrett, Hypergear and Mitsubishi!

Stao (Hypergear) seems to have come up with a solution and is always looking to improve his products.

Best solution, use a EXTERNAL GATE. If you dont want the noise plumb it back into the exhaust :)

Lithium...it makes between 295-305rwkw with a nice fat curve depending on the dyno and conditions on the day...and i agree...its not efficient at 30psi...just mentioned it to show it could be done...but it happened because a hose popped off the boost controller...painful affair actually...popped the engine at the track...

Hypergear...rb25 and 2JZ...big difference...not a valid comparison...just like a lot of your arguements...

And from your post...that boost curve isn't what i'd call smooth...this is smooth and this is what i'm after...but at 21-22psi

BoostStocktwinsvs3076.jpg

OK that does sound a little low, were any of those a Dynapack?

Have you gone into the duty cycle settings of the AVCR and picked up the duty cycle for higher rpm?

Yup...tried that...i was just tweaking it recently...it sat something like this from 2000rpm onwards at 500rpm increments...48% 48% 55% 60% 68%, 68% 68% and so on till 7000rpm...went as high as 80% while trying it on the dyno but didn't make much difference...

I chose this turbo because other RB30DET members on here have gotten good results on their cars with this setup...and with the 18psi garrett actuator too...yes the 3076R is a tad small for a 3L...i know that...but i chose it because peak power wasn't the aim...maximum response was the aim with 300rwkw in mind...and it does that...no complaints there...also...i wanted to be the first to do a low mount single setup in victoria just to prove it could be done...and i've proven it...have a look in the RB30 thread for some examples...i'm staying out of comparisons between rb25s here as a 2JZ is a whole different kettle of fish...

a friend has had a 3076 on his JZA80 for a while now, its a great setup you lose a little boost response vs the stock twins but gain a meaty midrange and its so smooth onto power.

a friend has had a 3076 on his JZA80 for a while now, its a great setup you lose a little boost response vs the stock twins but gain a meaty midrange and its so smooth onto power.

Agreed...it comes on so early and so nicely...for the 2 years i've had it on the car i have nothing but praise for the way it drives...just that now i wanna turn the wick up a little...you do lose a little response over the sequential twins below 3000rpm but with a small single i still hit max boost and max torque about 800rpm earlier than the twins and with a heap more midrange...

Hypergear...rb25 and 2JZ...big difference...not a valid comparison...just like a lot of your arguements...

And from your post...that boost curve isn't what i'd call smooth...this is smooth and this is what i'm after...but at 21-22psi

But on the same time you are running a EBC which will rule out all the little up and downs in the curve. All those boost curves you saw out of my sheets are not using boost controllers. Straight Vacuum into actuator and thats it.

Like you just can't stop baitting other people, while some one made it work is trying to advise you. The point of showing you a small 21U .58 can hold boost on a 2.5L is in the same principle as you are trying to hold boost with a .82 3L engine. On the same time the .58 would be cooping lot more back pressure and heat. If I can't get a .82 rear to hold on a 3L there is absolutely no way I can do it on a .58 with 2.5L.

Even you've got a GT3076 in .58 21U turbine I can still make it hold 22psi with your 3L engine.

Ok hypergear...point taken...i'm tired of arguing with you...lets agree to disagree... and leave it at that...

Scotty nm35...yup...you're right...no dodgy dip at the changeover point too....

You do realise if you welded the gate shut you could quite easily run 50psi all the way to redline if you really wanted? Knowing that it is just a matter of proper gate control to run any boost you want to redline, simply bleeding off the pressure line and increasing spring pressure is not enough though, need fancy tricks to get there.

However if you do need fancy tricks it says that the backpressure is very very high and you should probably be going to a bigger housing.

Rolls...with regards to your earlier post...do you reckon the flap is being blown open due to sheer pressure from the exhaust gases from a 3L at higher revs?

It is either that or the boost controller is not bleeding enough pressure to let the flap shut as much as required, being as you have tweaked the boost controller settings I would say it is the former.

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