gt3076r .63 vs .82 vs 1.06 a/r

[rwd]

i have a gt3076r with .63 hot side on 1jz , it's a torque monster,but i want more top end power. I think .63 it's too small for top end power,i only does 13's and 114mph ,i'm really disappointed . If i'll try to change the hot side for .82 or 1.06 , do i waste my money and i'll be better to go with bigger turbo

other option is change for gt40r or gt35r ???a/r

 

[tbcmorris]

I would run the 82

 

[Doward]

I believe Ian (IJ.) was running that turbo with a 1.06 and had great power across the board.

Hopefully, he'll chime in here

 

[IJ.]

Ran mine with the .63 it choked at 5000 on the 7M but made boost off idle.

I'd go 1.06, I ran that on the 3040r and it was amazing.

 

[rwd]

can i expect that my engine will rev faster , cause actually he rev slow like a oldschool v8

 

[IJ.]

It revs slow with the .63?

 

[rwd]

yes , after 4500rpm i've impression that the engine can not rev zippy,to much back pressure.I thought that the 1jz was high rev engine .I have a lot of power but it rev slow ,maybe i make mistake and it's normal!

when i went to dyno i compare my dyno sheet with stock twin dyno sheet,and i have exactly the same curve for torque and hp but 180-200 more,and i have 264 cam,single turbo,big intercooler!!

 

[IJ.]

Sounds about right as I said mine topped out around the 5000 mark and just fell on it's face

 

[Doward]

There ya go

 

[OneJSupra]

Wouldn't a 1.06 hot side on a 2.5L motor be laggy? My .68 hot side T61 turbo spool doesn't come on till 3200rpm. I can't imagine what spool will be like with a 1.06. I'm sure it will give a lot of top end but will be lag monster. Agreed with TBc would prolly be go with a .8x hot side.

 

[bloodasp90]

i had a .82 while i was in JDMland, and i wish i never got rid of that motor, it spooled down low it seemed pretty easly, and pulled all the way up to 8k where i stoped it.

 

[rwd]

Wouldn't a 1.06 hot side on a 2.5L motor be laggy? My .68 hot side T61 turbo spool doesn't come on till 3200rpm. I can't imagine what spool will be like with a 1.06. I'm sure it will give a lot of top end but will be lag monster. Agreed with TBc would prolly be go with a .8x hot side.

correct me if i'm wrong,but your t61 have t4 inlet , and .68 t4 vs 1.06 t3 must be pretty close

i'm not sure if i change just from .63 to .82 that will give me big difference , probably my turbo is too small for what i expected.if i stay gt30r i'll be stay in 13's or high 12's

someone can tell me ,if i put gt4088r or gt4094r , are they too big for 2.5, can i'll do 11's or 10's on quarter with that size, what a/r would be the best and twin scroll will help .today i realize that i prefer top end power than torque .And anyway, for street i always go to 7000rpm+

 

[IJ.]

.68 is .68 no matter what flange, t3/t4 makes NO difference if the wheels are the same size.

"AR" is a calculation based on Area of the nozzle into the turbine hosing where it's necked down x the radius of the wheel, the flange opening doesn't affect it.

 

[Doward]

Ian, I believe rwd is trying to say that the physical size of a specific A/R T3 vs T4 are vastly different.

In other words, you could see similar spool characteristics between a large .68 A/R T4 wheel vs a smaller 1.06 A/R T3 wheel

 

[IJ.]

A lot of the GT series turbos come with the option of T3/T4 flange and use the same wheels therefore the same AR calc, I've seen a LOT of people post misinformation that the flange changes how they spool so just wanted to clear it up before it happened here

 

[rwd]

sorry , my bad

in this case , do you think that small gt30r with 1.06 a/r will be lag monster

 

[IJ.]

Not at all the smaller wheel will accelerate much quicker due to it's lower PMoI compared to the turbine wheel in a 3540r, of course this is all just a guess on my part based on my experience with the 1.06 on the 3.0L.

I've spent a lot of time and $ playing musical turbine housings with the T04z and modern BB turbo's behave very differently to non bb old school turbos.

 

[xsjado]

A lot of the GT series turbos come with the option of T3/T4 flange and use the same wheels therefore the same AR calc, I've seen a LOT of people post misinformation that the flange changes how they spool so just wanted to clear it up before it happened here

So let me get this straight. I'll use my turbo for example, it was only offered in T3 .63, .82 and 1.06 from Turbonetics, but they made up a custom T4 .81(I think) exhaust housing for me. What you are saying is there should be no difference in spool between the T3 and T4 versions since they share the same exhaust wheel? If so that's good news, now to find out why it isn't coming on boost sooner than it should .

 

[IJ.]

Yep if it's the same wheel and the housing has the same nozzle cast into it there should be 0 difference as those are the 2 things that give you your AR number.

If someone got the casting wrong and the nozzle size is larger on the T4 version that would mean it's a bigger AR.

 

[BigSupe]

I have a gt3076r 1jz with a 0.82 and full boost 1.3bar is at 3800rpm and pulls hard all the way to the redline 372whp dyno'd

As you said a 0.63 would make boost instantly but will ultimately restrict top end power and be too twitchy for a street car?

A guy over here has a 1jz which is a edc drift car he has all three hotside sizes and he runs the 0.82 he said the 1.06 doesn't boost until after 5k rpm so way too laggy for a street car

Both cars are standard lumps with the usual bolt ons although he sometimes runs 1.8bar