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2 minutes ago, Kinkstaah said:

Top is the 3582. This is from a couple of years ago now, the most updated graph is in the Dyno section. (and is 'better')
Point really was explaining why I went up a turbo size was logical at the time.

Since then yes, I'm happier to run less boost/bigger exhaust/better manifold/different exhaust which has all happened since then actually.

But my way of thinking (and Trents, and Scotty who was also there that day) was the standard motor has a rev limit of 7000-7500 functionally, and this thing is very upset at 6000, so it can't really be ideal. I didn't just change it because I have an insatiable lust for MORE POWERRRR for fake internet recognition.

I'd much rather run something less hard and utilize the rev range the motor has/should have. Just feels better than beating the daylights out of a turbo to within an inch of its life. (moreso, I have overspun one of the GTXs!) and short shifting it.


Just didn't seem like the best of plans.

You have added displacement from a stroker kit, this changes the dynamics and gives your engine a low-mid advantage over the standard engine - I would be taking advantage of this instead of worrying about the top end, where displacement means much less in turbo applications. As long as it makes the power you desire, who cares if you're shifting at less than 6000rpm?

25 minutes ago, Birds said:

You have added displacement from a stroker kit, this changes the dynamics and gives your engine a low-mid advantage over the standard engine - I would be taking advantage of this instead of worrying about the top end, where displacement means much less in turbo applications. As long as it makes the power you desire, who cares if you're shifting at less than 6000rpm?

Apparently Greg does. 

Greg doesn't really, but that behaviour certainly wasn't seen in engines larger in capacity (like 3L 2JZ's).

There's also no actual advantage once you're moving if your powerband is from 3K to 6K vs 4K to 7K RPM. To a certain extent, you can just rev the smaller displacement more.

In any case, there was clearly something wrong, and I needed more flow out the turbine end or less restriction. That meant a 1.06 rear, or realistically a GT35 turbine with a .82. I did consider a GT3576R in .82 which would have been just fine, but the GTX3582 was

a) Cheaper (I got it for $1400 new) I could sell the near-new GTX3076R, so I lost nothing in the swap over. It was cheaper for me to go GTX3582 vs putting a 1.06 rear on the GTX3076R.
b) Easier, the GTX3582 is a proven product and definitely one of the 'best' turbos that garret made in the GTX range. The GTX3576 was more unknown, and more expensive, and made less power, and was a more expensive way of putting a 1.06 rear on the GTX3076R really.

Keep in mind 22psi, it's not like I was trying to max the thing out and make 550RWKW at 40psi that some people do with them.
There is method to the madness!

1 minute ago, Kinkstaah said:

Greg doesn't really, but that behaviour certainly wasn't seen in engines larger in capacity (like 3L 2JZ's).

There's also no actual advantage once you're moving if your powerband is from 3K to 6K vs 4K to 7K RPM. To a certain extent, you can just rev the smaller displacement more.

In any case, there was clearly something wrong, and I needed more flow out the turbine end or less restriction. That meant a 1.06 rear, or realistically a GT35 turbine with a .82. I did consider a GT3576R in .82 which would have been just fine, but the GTX3582 was

a) Cheaper (I got it for $1400 new) I could sell the near-new GTX3076R, so I lost nothing in the swap over. It was cheaper for me to go GTX3582 vs putting a 1.06 rear on the GTX3076R.
b) Easier, the GTX3582 is a proven product and definitely one of the 'best' turbos that garret made in the GTX range. The GTX3576 was more unknown, and more expensive, and made less power, and was a more expensive way of putting a 1.06 rear on the GTX3076R really.

Keep in mind 22psi, it's not like I was trying to max the thing out and make 550RWKW at 40psi that some people do with them.
There is method to the madness!

Less restriction I agree with, am all for the engine being able to breath and less stress on it and components, and if that makes more power up top then great - better to have and not need it...just feel like your setup is/was not reflecting what you desired in a vehicle. Turbos are always a compromise between lag and power; seems to me you're taking on unnecessary lag for a better top end that you can't/won't even use, when you could be looking at a wastegate or custom rear end solution to produce response without the detrimental restriction.

This top end large turbo stuff makes sense in race cars, like the 80s rally cars that ran GT35 sized turbos on 1.5 engines etc. Street driven, occasional track cars work better with small turbos driven harder IMO. Be faster in most places rather than one place. Tony will tell you how much this helps me with the rolling drags for instance. Subaru, Mitsi and Mercedes have embraced this on their 2 litre engines which see 14-18psi+ in standard form with their small turbos.

What manifold are you running again Greg? 

This is all running on a flowed out manifold that Tao from hypergear made.


Before OH LOL STOCK MANIFOLD CAUSING PROBLEMS. I am able to put a 4psi spring in the wastegate and I get absolutely zero boost creep, it'll happily vent and run at 4psi all day at any load at any RPM. Plenty of others have gone tracking much harder than I have with gates off stock manifolds or turbo housings.

I'm still planning on changing the manifold anyway.

For comparison sake - tapers in the top end, well before 6000rpm (my rev limit is 7500), but it's more linear and plenty of area under the curve = huge midrange to work with

This is a 3071 equivalent turbo pushing only 15psi - rest goes out the large internal wastegate. With an extra 300cc, it's very odd that a 3076 shouldn't produce a similar curve for you - definite restriction but I don't think the turbo itself was the problem.

IMG_5738.JPG

 

2 minutes ago, Count Grantleyish said:

I'm impressed it made that much power, especially with T3 flange actually. 

Or has it been "converted" to T4 flange? 

T3 Flange, and it was making that through an auto so... 460kw? Yes that's very high. I also thought that may have been a problem, but I never experienced any boost creep. Hence my test with 4psi.. which also does not creep. I guess the logic that the ports all have to converge in a flange of some sort is sound, though not as nice or as smooth as a T4 Twin scroll setup.

2 minutes ago, Birds said:

Less restriction I agree with, am all for the engine being able to breath and less stress on it and components, and if that makes more power up top then great - better to have and not need it...just feel like your setup is/was not reflecting what you desired in a vehicle. Turbos are always a compromise between lag and power; seems to me you're taking on unnecessary lag for a better top end that you can't/won't even use, when you could be looking at a wastegate or custom rear end solution to produce response without the detrimental restriction.

This top end large turbo stuff makes sense in race cars, like the 80s rally cars that ran GT35 sized turbos on 1.5 engines etc. Street driven, occasional track cars work better with small turbos driven harder IMO. Be faster in most places rather than one place. Tony will tell you how much this helps me with the rolling drags for instance. Subaru, Mitsi and Mercedes have embraced this on their 2 litre engines which see 14-18psi+ in standard form with their small turbos.

I entirely agree with this sentiment, but the GTX3582 did drive better than the GTX3076 did as well, better transient repsonse, just better everything really. The GT35 wheel felt a lot 'better' than the GT30 wheel ever did in the setup. Neither setup was laggy with the auto spooling it up and getting it all going. There almost no need to ever change gears out of 4th (same ratio as 5th in manual land). Just give it 40% throttle and let the auto take care of the rest. Had quite a few people drive it and comment on how it didn't even seem to matter what gear it was in when you're at a cruising speed driving along in the road.

Small turbos driven harder is good. 18psi is "harder" but that is not 35psi. I've never run more than like 22-25psi on my car, because I'm not chasing some record breaking theoretical dick measuring max, I just want what I've got to work pretty efficiently and work 'well' for what's in there.

186kph is about 6500rpm.

3 minutes ago, Kinkstaah said:

T3 Flange, and it was making that through an auto so... 460kw? Yes that's very high. I also thought that may have been a problem, but I never experienced any boost creep. Hence my test with 4psi.. which also does not creep. I guess the logic that the ports all have to converge in a flange of some sort is sound, though not as nice or as smooth as a T4 Twin scroll setup.

I entirely agree with this sentiment, but the GTX3582 did drive better than the GTX3076 did as well, better transient repsonse, just better everything really. The GT35 wheel felt a lot 'better' than the GT30 wheel ever did in the setup. Neither setup was laggy with the auto spooling it up and getting it all going. There almost no need to ever change gears out of 4th (same ratio as 5th in manual land). Just give it 40% throttle and let the auto take care of the rest. Had quite a few people drive it and comment on how it didn't even seem to matter what gear it was in when you're at a cruising speed driving along in the road.

Small turbos driven harder is good. 18psi is "harder" but that is not 35psi. I've never run more than like 22-25psi on my car, because I'm not chasing some record breaking theoretical dick measuring max, I just want what I've got to work pretty efficiently and work 'well' for what's in there.

186kph is about 6500rpm.

Perks of auto - are you going manual though?

I would like to, though I have no real "reason" to get rid of the auto which admittedly works pretty fkin well and refuses to die.
I would NOT recommend this turbo on a 2.5, especially not on a manual 2.5, and wouldn't even without a custom stall converter on an auto. it'd be fkin crap. No power till 5k and a 7k redline = shit life.

The reason I wanted a smaller turbo, that makes ~320-340 is that is close to the allowable max of a manual gearbox as well. It's a little bit over actually, but its not complete instant death to the gearbox...

I actually would prefer a 7163, but given that MAXES OUT HARD at about 320-330kw and there is danger of overspinning them... I'll go one size up and run it at 80%.

See? Logical!

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