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Old 11-09-2020, 07:31 PM   #1
FQ06
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Default Cobb 20g or BNR 20g?

Trying to make a decision on this...
I'm going from a GT30R (not billet wheel) to a quicker spooling 20g. Also swapped out my FMIC for a PW TMIC. I have a 2.6L stoker motor so I shouldn't have much lag even with a 20g... at least less than with the GT30.

I'm not expecting much difference between the two 20g's but thinking the BNR may flow a little better with gasket match porting and maybe a better journal bearing.

Thoughts from the forum on the two turbos and what you think would be the better choice?
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Old 11-10-2020, 05:12 AM   #2
07imprezRS
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What are your power goals? Are you ok with compromising top end loss in comparison to the GT30? Have you looked into the Blouch 20GXTR ball bearing series? They provide quick spool up and good mid range power and hold most of the way to redline. I believe a ball bearing turbo like the Blouch will spool slightly quicker than most standard journal bearing models of similar size.
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Old 11-10-2020, 10:24 AM   #3
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I don't really have a HP goal, been there done that with the GT30. Looking for quicker spool for around town driving without running out of power at the top end. I'm also trying to stay within a budget of around $1k, I guess the 20gxtr isn't too far above $1k but it is almost double the BNR price. Possibility of running 3" into the turbo is appealing with the Blouch though...

I've heard good things about the BNR 20g and Cobb puts out quality stuff so I guess either would be an OK choice but just wondering what the community's opinion was on those two turbos.

Last edited by FQ06; 11-10-2020 at 10:58 AM.
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Old 11-10-2020, 02:23 PM   #4
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Quote:
Originally Posted by FQ06 View Post
I don't really have a HP goal, been there done that with the GT30. Looking for quicker spool for around town driving without running out of power at the top end. I'm also trying to stay within a budget of around $1k, I guess the 20gxtr isn't too far above $1k but it is almost double the BNR price. Possibility of running 3" into the turbo is appealing with the Blouch though...

I've heard good things about the BNR 20g and Cobb puts out quality stuff so I guess either would be an OK choice but just wondering what the community's opinion was on those two turbos.
I have a Cobb 20G available within your budget.

https://forums.nasioc.com/forums/sho...2#post46457242
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Old 11-10-2020, 02:47 PM   #5
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Donít get me wrong on the BNR and Cobb applications, they are great. I just think that for $400-$500 more you could see roughly 300-400rpm quicker spool up generally with a ball bearing model. Food for thought. Doesnít sound like much on paper but it makes a difference when you mash that accelerator! 20g from Cobb is a proven turbo though. I myself am planning for an 18gxtr Blouch with 38mm ewg setup on my Hawkeye. Great response setup, and wonít break the bank. I already have the ewg up pipe from grimmspeed and tial valve. Using a tried and true invidia catless bell mouth down pipe just like I have on my bugeye wrx. Gotta love AZ, no catalytic converter needed in my county.
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Old 11-10-2020, 08:14 PM   #6
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Quote:
Originally Posted by JSR84 View Post
I have a Cobb 20G available within your budget.

https://forums.nasioc.com/forums/sho...2#post46457242
Throwing a new turbo on, thanx though
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Old 11-10-2020, 09:32 PM   #7
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I've been debating the 18g because I would really like to play in the other side of the power curve for a while. I've ran 420 at the wheels since about 2012 and am looking for a different drive giving some hp up for quicker spool.
I run a 2.6L stroker though so I think I can get away with the 20g and not see much more lag than a 2.5L with an 18g... fingers crossed.

I've ran catless in Los Angeles since about 2012, didn't have a loud muffler so cops didn't hassle me. Especially after the hellcats & others became more common, those are loud. I had a high flow cat welded in because I got tired of the stink that followed me up to a stoplight lol. Seat of the pants, no noticable difference in bottom end.

I've heard both sides of journal vs ball bearing and lean towards ball bearing spoiling faster but I think any of the above would satisfy my want for quicker response coming from a GT30R with 60k miles on the clock

Really just wrestling with BNR or Cobb. Or even a ball bearing VF48 20G from Hill country forced induction, that was on my list... not sure how it fell off. Adrian was saying BB is worth about 300 rpm worth of quicker spool. But he offers that service for a fee. BNR says no difference and journal holds up better, he doesn't offer that service for a fee... so I have to take those opinions with at least one grain of salt. HCFI all in is about $1,250 so again creeping up on the Blouch $1,500 lol.


Quote:
Originally Posted by 07imprezRS View Post
Donít get me wrong on the BNR and Cobb applications, they are great. I just think that for $400-$500 more you could see roughly 300-400rpm quicker spool up generally with a ball bearing model. Food for thought. Doesnít sound like much on paper but it makes a difference when you mash that accelerator! 20g from Cobb is a proven turbo though. I myself am planning for an 18gxtr Blouch with 38mm ewg setup on my Hawkeye. Great response setup, and wonít break the bank. I already have the ewg up pipe from grimmspeed and tial valve. Using a tried and true invidia catless bell mouth down pipe just like I have on my bugeye wrx. Gotta love AZ, no catalytic converter needed in my county.
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Old 11-12-2020, 09:07 AM   #8
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Quote:
Originally Posted by FQ06 View Post
I've been debating the 18g because I would really like to play in the other side of the power curve for a while. I've ran 420 at the wheels since about 2012 and am looking for a different drive giving some hp up for quicker spool.
I run a 2.6L stroker though so I think I can get away with the 20g and not see much more lag than a 2.5L with an 18g... fingers crossed.

I've ran catless in Los Angeles since about 2012, didn't have a loud muffler so cops didn't hassle me. Especially after the hellcats & others became more common, those are loud. I had a high flow cat welded in because I got tired of the stink that followed me up to a stoplight lol. Seat of the pants, no noticable difference in bottom end.

I've heard both sides of journal vs ball bearing and lean towards ball bearing spoiling faster but I think any of the above would satisfy my want for quicker response coming from a GT30R with 60k miles on the clock

Really just wrestling with BNR or Cobb. Or even a ball bearing VF48 20G from Hill country forced induction, that was on my list... not sure how it fell off. Adrian was saying BB is worth about 300 rpm worth of quicker spool. But he offers that service for a fee. BNR says no difference and journal holds up better, he doesn't offer that service for a fee... so I have to take those opinions with at least one grain of salt. HCFI all in is about $1,250 so again creeping up on the Blouch $1,500 lol.

I have a twin scroll VF36 that was rebuilt and upgraded with a BB center from Adrian at HCFI. This is on a stock 04 sti that originally had the stock vf/headers.

The twin scroll made a lot of difference in off boost/drive ability. The VF36 ball bearing was the cherry to complete the package. Adrian knocked it out of the park with the porting/polishing. Turbo sings and sings pretty well at the top end for being small. It's no 18g/20g ... but for my style driving I don't spend a lot of time up there and it does exactly what I wanted. Lower end/mid range is where it shines.

Whichever turbo you go with... I would also recommend going with a BB. I really enjoy my throttle/boost response.
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Old 11-12-2020, 01:58 PM   #9
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i have kinugawa 20g w/11blade turbine, spools nice compared to the vf48...is journal bearing too, would prefer the ball bearing for spool but i got a good deal on this and it works great!
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Old 11-12-2020, 02:51 PM   #10
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I've been running a Blouch 20g xtr for about 6k miles now. I hit full boost (21psi) at around 3400rpm and it holds it all the way to redline. Great spool and great for street/highway driving I'd definitely recommend it as a good midframe ball bearing turbo.
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Old 11-12-2020, 06:27 PM   #11
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Thanx for the input, appreciate it.
One item is left for my decision...
I had the aps 70mm CAI and changed to a cobb SF which I think has a 2.5" maf tube so the intake route would be choked down from the start of I'm correct. I still have the aps big inlet pipe so I'm wondering if anything after the Cobb SF maf tube makes any difference. Like the blouch has a 3" inlet option, great! Matches up with the inlet that's currently on the car... but would it make any difference if inlet pipe and turbo housing inlet is 3" if the Cobb maf tube is 2.5"?
I'm leaning towards the blouch 20g with the sole reason being a 3" inlet but maybe I could see the same results for $500 cheaper going with the ball bearing Hill country vf48 that has a 2.5" inlet?

Quote:
Originally Posted by horsePOOGAS View Post
I have a twin scroll VF36 that was rebuilt and upgraded with a BB center from Adrian at HCFI. This is on a stock 04 sti that originally had the stock vf/headers.

The twin scroll made a lot of difference in off boost/drive ability. The VF36 ball bearing was the cherry to complete the package. Adrian knocked it out of the park with the porting/polishing. Turbo sings and sings pretty well at the top end for being small. It's no 18g/20g ... but for my style driving I don't spend a lot of time up there and it does exactly what I wanted. Lower end/mid range is where it shines.

Whichever turbo you go with... I would also recommend going with a BB. I really enjoy my throttle/boost response.
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Old 11-12-2020, 10:54 PM   #12
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Thanx GK & jedi, blouch it is. Maybe the 3" inlet helps or it doesn't depending on the ID of the SF intake maf tube... but it's not going to hurt
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Old 11-15-2020, 01:03 PM   #13
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You could pick up a Kinugawa ball bearing td06 billet wheel 20g with 3in intake for $950. That'd by my route if I were looking currently. Brand new with all the best features.

http://shopping.kinugawaturbo.com/ki...s-3-1-3-3.aspx
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Old 11-17-2020, 11:50 AM   #14
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I commented on your thread in the 2.0 forums but It got abandoned lol.

My 2 cents is if you are prioritizing spool up, go for something ball bearing 100%. Skip the standard Cobb 20g and consider a Blouch 20GXTR, same top end, better spool up.

And personally, for your setup, I would go for a 1.5XTR over a 20g. You'll get similar spool on the 1.5 to a standard journal bearing 20g, but with a good bit more power up top.
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Old 11-17-2020, 12:30 PM   #15
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If vf48 is one of your option, you should check out the new IHI vf48 HF (high flow), it cost around $1K
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Old 11-18-2020, 07:33 PM   #16
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Quote:
Originally Posted by K3rm1tth3fr0g View Post
I commented on your thread in the 2.0 forums but It got abandoned lol.

My 2 cents is if you are prioritizing spool up, go for something ball bearing 100%. Skip the standard Cobb 20g and consider a Blouch 20GXTR, same top end, better spool up.

And personally, for your setup, I would go for a 1.5XTR over a 20g. You'll get similar spool on the 1.5 to a standard journal bearing 20g, but with a good bit more power up top.
Pushed the button today, 1.5xtr 8cm housing, 3" inlet.
After hearing from this group, talking to AQ motorsports and Church tuning, I am probably leaving more topend on the table than I should but I am looking to really move the power to the bottom end. Worse case if I really miss the party above 6k, I'll swap out the hot side for a 10cm.
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Old 11-18-2020, 07:35 PM   #17
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Quote:
Originally Posted by lowbee View Post
If vf48 is one of your option, you should check out the new IHI vf48 HF (high flow), it cost around $1K
I've got too much motor to stick with a stock size turbo. I can, but coming from a GT30R, I need to slowly come down from the big turbo high
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Old 11-18-2020, 07:39 PM   #18
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Quote:
Originally Posted by rexblake View Post
You could pick up a Kinugawa ball bearing td06 billet wheel 20g with 3in intake for $950. That'd by my route if I were looking currently. Brand new with all the best features.

http://shopping.kinugawaturbo.com/ki...s-3-1-3-3.aspx
Read decent results for the money but the casting just looks awful on the outside, I can't imagine how it looks where you can't see it and where it counts.
I don't mind spending a little over the norm on the turbo, I got my $ worth out of that gt30 running it more than 60k miles
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Old 11-18-2020, 07:50 PM   #19
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I'd give Arashi turbo especially their KBT version a serious look
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Old 11-19-2020, 02:32 PM   #20
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Quote:
Originally Posted by FQ06 View Post
Pushed the button today, 1.5xtr 8cm housing, 3" inlet.
After hearing from this group, talking to AQ motorsports and Church tuning, I am probably leaving more topend on the table than I should but I am looking to really move the power to the bottom end. Worse case if I really miss the party above 6k, I'll swap out the hot side for a 10cm.

That's a good choice. Please post th dyno graph if possible. I'd be interested in seeing.
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Old 11-20-2020, 10:00 AM   #21
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Quote:
Originally Posted by FQ06 View Post
Pushed the button today, 1.5xtr 8cm housing, 3" inlet.
After hearing from this group, talking to AQ motorsports and Church tuning, I am probably leaving more topend on the table than I should but I am looking to really move the power to the bottom end. Worse case if I really miss the party above 6k, I'll swap out the hot side for a 10cm.
That's a great compromise of spool up/response with top end power.

Can't wait to see your dyno chart.

Good luck
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Old 11-25-2020, 03:00 PM   #22
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Quote:
Originally Posted by lowbee View Post
I'd give Arashi turbo especially their KBT version a serious look
That's a good looking cheap turbo, might have gone that route but no buyers remorse here, looking forward to the blouch.
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Old 11-25-2020, 03:01 PM   #23
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I'll post the dyno sheet in a few weeks once the tune is done.
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Old 11-27-2020, 12:36 PM   #24
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I have been running an Arashi TD06 sl2 20g for about 20,000 miles now and in all its been a great turbo on a 11 wrx fully built with front mount. Hits 21 psi at about 3600-3700 rpms and holds 19 to 20 to redline no problem. I was gonna go with one of the ball bearings but I put a lot of miles on this car daily driving 100 miles a day so I went with journal style turbo for longevity. And for 750 shipped it was a steal in my mind compared cobb.

Just Looked at Cobb and they show it on Back Order anyways so might be tough to find anyway.

Last edited by saaiello21; 11-27-2020 at 12:45 PM.
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Old 11-27-2020, 05:19 PM   #25
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Quote:
Originally Posted by FQ06 View Post
Trying to make a decision on this...
I'm going from a GT30R (not billet wheel) to a quicker spooling 20g. Also swapped out my FMIC for a PW TMIC. I have a 2.6L stoker motor so I shouldn't have much lag even with a 20g... at least less than with the GT30.

I'm not expecting much difference between the two 20g's but thinking the BNR may flow a little better with gasket match porting and maybe a better journal bearing.

Thoughts from the forum on the two turbos and what you think would be the better choice?
What kind of numbers where you running with the GT30?
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