Whats your opinion about the GT3540

[EldarO]

im looking forward to Ezra's (Byteme) 2J starting up, afaik its a 3540 with a .63 rear housing :|

my bad, he just told me, its a .68, same same IMO

[30psi 4agte]

the only time id use a .63 on a gt35 would be on a 2L engine with small cams.

cheers
linden

Or a 1.6L

I have seen the vl guys using the .63.... Its fairly common --- but im with you inden.. too small for a engine of that size..

Id be going for the .82 if it was primarily a street car with ocasional strip/track work or the 1.06 if its a all out racer.

P.S...I dare say it is a .63 if we are talking about the 3540 ... they are the three STD sizes for that charger.

[byteme]

the turbo im using is a Master Power T70 (the one with the .68 rear)

there is a fella on supra mania making 400+ rwhp on the same turbo on his 2jzge-t

[EldarO]

oh, you told me you had GT35 fag, not some shitty egay turd.

wil edit out misconceptions of coolness.

[byteme]

i never said it was a gt35....youve just been bitch slapped to much to remeber i told you it was a t70

[annoyingrob]

I would go for the .8x a/r gt3582R. Yes it will be a bit laggy but I think full boost should be achieved by 4500rpm. If you want big power you have to have lag.

It should not be THAT laggy. My 1JZ ran a GT4088, and would hit 18psi by 4600rpm with a .81 exhaust housing. Started making boost by about 2800.

I run the same on a 1.5JZ now, and it's a good match. Boost by 2500, hitting 18psi around 4000. Even at 3k(5psi), it's enough to break the rear-end loose in less then ideal conditions in low gears. 1st and 2nd are just smoke shows with 4.10 gears and 285s.

A GT35R on a 1JZ IMO would be a great turbo.

[Smokey228]

So im looking at a gt3540 with .7 front and .82 rear... When can i expect to start making boost and when will i see full boost?

I kinda want to do some track work and this is why im hesitant about it! For street and drag i think it'd be fun though

Cheers,
Jase

[ATMO_BT1]

GT3040 (aka 3072r) is very very similar to the GT3540 (aka 3582r), the rear wheel is the only difference and lag wise you will find it very different to pick the two apart. On a twin cam 2.5L like the 1JZ i think you would be crazy to go any smaller than a .82 rear ended GT3040 or GT3540r. If the car was more of a drag car than a track car i would go 1.06 and make some serious hp but for a manual, street driven occasional track weapon the .82 3540 (and to a slightly lesser degree, 3040) is my pick of the bunch.

Last week i pulled the rear end off a 3540 and compared it to a deconstructed 3040 and the difference is minute in rear wheel inducer/exducer visually.

My car is a built and cammed 3L single cam (RB30ET) so it's not too far fetched to think that response wise it would be similar to the far better designed 2.5L toyota twin cam in standard form. I found the 3040 too small personally and will be going for a t04z next (manual). The 3540 i am currently fitting is simply a patch-up fix to get the car on the road asap as i am sick of not driving it.

I used to be of the school of thought that lag was a turbo cars worst enemy, after wasting time with the 3040 I now understand that a bit of lag is more than a fair trade off for adequate power. I'd rather have enough hp to keep me smiling with a little bit of lag than not enough hp and less lag- i mean we build fast cars to go fast, not to prevent lag- if you know what i mean... so stick with your priorities

Just my 2c, although with the strength of my dollar at the moment it might be worth a little more.

[chris davey]

.63 gt3582R on a 1j has made 24psi at 4200rpm. I would think 4500rpm or so for the .82.

atmo bt1, you mean gt3082R right?

I like the looks of the 3076, 3082 for a good street turbo with occasionaly track use. Potential for a tad over 300rwkw with these with a good setup. (.8 turbine a/r)

3582 with .63 doesn't seem right personally as I think the exhaust housing will become a restriction too early.

3582 with .8 is good for around 350rwkw on 1j without nitrous. Derek johns on here has made 458rwkw and run mid 10s in a commodore using some good fuel and 100shot of nos from memory.

[ATMO_BT1]

I actually meant to write 3076r (i think!) sorry for the confusion, i usually just call them all GT30s or GT35s to save confusion, as usually they just denote when the turbo was built (ie the GT3040 is the older GT30, as that is what Garrett used to call them).

I totally agree that the .63 rear will choke on a 1jz very early. Surge may also become a problem as it ramps up.

[Smokey228]

See i dont intend to see that kinda power... I want to see 250rwkw for a street / circuit car...

I can see that a 30/40 will get me there, well inside its efficiency range aswel! But i dont see why going to a gt3540 will do me any favours, bar the obvious room for improvement!

Though the turbo will make that same power with less pressure, its not like the 30 is moving beyond, or is even relatively close to its efficiency border!

So basically, im giving up that extra few hundred RPM for the posibility that i may, one day, want to move onto a bit of extra power... Which i dont really see happening on a car that will probabaly see the drag strip on 2-3 occasions... Primarily spending track time on a good ol circuit ironing both, its driving and my own driving issues! And virtually all its days on regular australian roads!

But plz, educate me further as this is just the way i see it. I have been known to be heading in totatlly wrong directions before!

Cheers,
Jase

[ATMO_BT1]

The difference in lag will be very minimal as the housings are exactly the same so volume wise the turbo is ingesting the same amount of air from the rear, it just spins in a more aggressive manner with the 35/40 due to wheel design and inducer/exducer size.

Either turbo will do although i would personally go for the 35/40 any day of the week, then again i'm sick of doing things twice i like to shoot for overkill and enjoy something in between

Remember, you have no idea what 250rwkw in a Celica is like as you haven't driven one yet... what's to say you won't get it and realise that the "feeling" you wanted was really 300? That's what happened to me..

[Smokey228]

300 in the celica is hypo77 ballpark man. I dont want to run 10's... lol He sat on shy of 450rwhp... 300rwkw is equal to around 400rwhp? thats a mid to high 10. Depending who's driving...

So the compressor housings are identical in size?
Exhaust housings are identical in size?
Compressor wheel is identical?
The only different is the design of the exhaust wheel?

Because of this exhaust wheel, the turbo spools a little later, but has the ability to produce more boost at higher rpm?
Is this because the design allows it to spin faster?

Cheers,
Jase

[ATMO_BT1]

You got it right there mate, although RPM wise i believe the turbo will spin no faster... the wheel design and size of the 35 is just more efficent at high rpm and/or high boost than the 30.

[chris davey]

300rwkw is 400rwhp and in a 1200kg car that should trap 133mph Plenty fast

For 250rwkw, you can either HF stockers, push the stockers till they break, gt3071R will do that with similar response to stock, gt3076 HG TR44, KKR 480 at around 16psi. (latter 2 being less responsive)

Or HG TR43 HF or KKR 430 are similar but cheaper versions of the gt3071.

I was after 300rwkw initially and went for tr44. It made 236rwkw@15psi and I ran 12.1@118mph at similar weight to your car. With a better 60 foot, that power is good for 11.3's. That is "only" 236rwkw so don't get caught up with dyno numbers too much