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Old 06-29-2023, 06:53 PM   #51
spoolinsti05
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With a 207 I'd keep the .82 since it has higher RPM rev limit. I'd get a .102 actually if you can even find one. They're rare this day in age.

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Old 06-29-2023, 08:38 PM   #52
Mauled
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Hmm 2 conflicting answers lol. I bought the 63 if it's too small ill get the 82. I can't see the 82 spooling any earlier then 5.5k. The gtx35 is basically a gt40r.

Wish I had a dyno to put the car on.
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Old 06-29-2023, 10:28 PM   #53
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Quote:
Originally Posted by Mauled View Post
Hmm 2 conflicting answers lol. I bought the 63 if it's too small ill get the 82. I can't see the 82 spooling any earlier then 5.5k. The gtx35 is basically a gt40r.



Wish I had a dyno to put the car on.
It won't spool earlier but it will give you better mid and top end performance. You can adjust the ignition timing for better low end performance. To a certain extent. Or your tuner can ramp the avcs timing. For adding in spool time. The .63 is small for that high revving engine.

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Old 06-29-2023, 10:29 PM   #54
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Quote:
Originally Posted by spoolinsti05 View Post
It won't spool earlier but it will give you better mid and top end performance. You can adjust the ignition timing for better low end performance. To a certain extent. Or your tuner can ramp the avcs timing. For adding in spool time. The .63 is small for that high revving engine.

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And the gt35x is more like a gt37r.

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Old 06-30-2023, 11:02 AM   #55
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https://forums.nasioc.com/forums/sho....php?t=2925900

.63 seems to work just fine for that guy. Later on he wanted to downsize his turbo to the 3076 lol.
https://forums.nasioc.com/forums/sho....php?t=2920024
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Old 06-30-2023, 11:02 AM   #56
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https://forums.nasioc.com/forums/sho....php?t=2925900

.63 seems to work just fine for that guy. Later on he wanted to downsize his turbo to the 3076 lol.
https://forums.nasioc.com/forums/sho....php?t=2920024
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Old 06-30-2023, 12:16 PM   #57
Mauled
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I'll try the 63 first I want it to pack a punch in the mid range and hopefully pin me to the seat till redline. I found oil leaking out of the bottom of my driver side head gasket so looks like I'm gonna pull the motor this weekend and re do the head gasket.
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Old 07-06-2023, 11:13 AM   #58
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I bought both housings wheres FuJi K I need his opinion on which one to run.
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Old 07-06-2023, 02:21 PM   #59
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https://fb.watch/lCLXtDJu-W/

Don't get stuck on the smallest A/R

Quote:
Originally Posted by spoolinsti05 View Post
And the gt35x is more like a gt37r.

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Not really

Modern turbo and engine configs perform quite well with large A/Rs
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Old 07-06-2023, 04:12 PM   #60
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.63 is too small , egt and backpressure will be through the roof , huge imbalance across hot and cold sides

a gt35x is just like a gt35x , it's not like a 37r or 40r as they have larger turbine wheels
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Old 07-06-2023, 05:14 PM   #61
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Quote:
Originally Posted by motorbykemike View Post
.63 is too small , egt and backpressure will be through the roof , huge imbalance across hot and cold sides

a gt35x is just like a gt35x , it's not like a 37r or 40r as they have larger turbine wheels

Bingo
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Old 07-07-2023, 11:15 AM   #62
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So even on a 2 liter .63 is too small?

I know it isn't even the same motor but my friend ran a .63 on his 35r on an inline 6 2.5l, which I would think would have way more backpressure, but it pulled like a freight train.

I'm not disagreeing with you guys just worried about lagging in between shifts.

I'll ask my tuner and see what he says but I'll also take your guys advice and try the .82 first. Might even try tuning both and see the difference.

Last edited by Mauled; 07-07-2023 at 11:38 AM.
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Old 07-07-2023, 11:41 AM   #63
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I think a .63 is fine for a 2.0 on pump gas. If you were running E85 or planning to max the turbo out then yeah .82 for sure. You are complaining about the 3076 with the .82 being laggy, the 3582 with a .82 will be worse.
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Old 07-07-2023, 11:50 AM   #64
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Quote:
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I think a .63 is fine for a 2.0 on pump gas. If you were running E85 or planning to max the turbo out then yeah .82 for sure. You are complaining about the 3076 with the .82 being laggy, the 3582 with a .82 will be worse.
It's not laggy if I shift at redline. Also running meth, not that it helps with spool. Seen a guy on here with a gt35r .63 making 468whp. I think the .63 gtx could hit 500. Like you said I'm not maxing the turbo out, 26psi so I don't think the .82 will make a big difference unless I'm running high boost.
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Old 07-07-2023, 12:00 PM   #65
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Quote:
Originally Posted by Mauled View Post
So even on a 2 liter .63 is too small?



I know it isn't even the same motor but my friend ran a .63 on his 35r on an inline 6 2.5l, which I would think would have way more backpressure, but it pulled like a freight train.



I'm not disagreeing with you guys just worried about lagging in between shifts.



I'll ask my tuner and see what he says but I'll also take your guys advice and try the .82 first. Might even try tuning both and see the difference.
It's not necessarily about being too small to work, it's about limiting power and response throughout the rev range vs a larger housing.

Even with a small displacement motor, the high efficiency turbos these days don't need tiny A/Rs to respond well and be efficient.

Don't take what your buddies inline 6 did and apply it to your setup.

I'd stay on the .82 even on your 2.0, maybe even move over to a 1.XX to make the power and truly more linear.
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Old 07-07-2023, 12:10 PM   #66
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https://www.garrettmotion.com/news/n...-turbo-system/
You have both housings and they're easy enough to swap out since you have a rotated setup. So just start with one, and if you don't like it/it doesn't meet your goals, then swap in the other one.

Last edited by HughGordon; 07-07-2023 at 12:25 PM.
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Old 07-11-2023, 03:29 PM   #67
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Ok I'm going to run the .82, what fuel pump should I run. Will 255lph be enough? Keep in mind I'm not running e85.
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Old 07-11-2023, 07:23 PM   #68
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run a AEM 340 or even the walbro 450
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Old 07-11-2023, 08:57 PM   #69
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If you want better spool get adjustable cam gears. You could advance the exhaust cam timing slightly. And adjust the tune. You could add more ignition timing before 10psi or so. Idk without seeing your data. Or get a 2.5L with a 207 you'll only get a power band from 4-8k

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Old 10-10-2023, 05:49 AM   #70
syamonz
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Quote:
Originally Posted by K3rm1tth3fr0g View Post
Many many variables here. Too many to say anything with certainty.

Going from a GT30 to a GT35 will certainly open up the topend while killing midrange, but exactly how much depends on the turbo.

The 3576 Gen 2 is actually a more balanced turbo than the 3076 you're on now, of which it shares its compressor wheel dimensions. It's much better suited for 500+ applications than the 3076. I have a Gen 2 3576 in my garage waiting for my built motor.

Without corn makes hitting 500 tougher but the meth of course helps - you just risk the meth system failing and the motor blowing up at high RPM... Such is life without corn.

I would guess going to a 3576 with a .82 you'd spool just a hair later with a lot more topend. Being a 2.0L though does seriously hinder spool and boost threshold though.

There are many schools of though regarding A/R selection. .82 is a good middleground for most setups, with the 1.xx A/Rs typically either killing spool/boost threshold, or making the motor feel more N/A like with a more linear power delivery. The ladder of which can actually be preferable. .63 will hit hard but drop off, not really what you want if you're sizing up to a GT35, though on a 2.0L a GT35 w/ a .63 house makes much more sense than a 2.5L.

I'd stay .82 probably though if you are up-sizing turbos.

With a 3576 you could probably hit 500 with meth. Same with 3582 but the spool and response will be considerably worse.

Do you have a tuner who you can discuss options with? They are always a good resource to engage if possible as they have a good understanding of the ramp rates, and how A/R affects power and spool. I would advise getting on a dyno rather than E-tuning a setup like this.

Not to throw another wrench in the mix but the EFR turbos also kick ass.
May be worth getting your head ported for high RPM
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Old 10-10-2023, 05:50 AM   #71
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Maybe worth getting your heads ported
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