will my ct-26 blow if I don't turn down boost?

87sleeper · 11-29-2005, 06:33 PM

hi, i'm new to the forum and modding my supra...I recently shimmed my wastegate (link form supra_girl I believe) with 4 washers, that gives me about 9psi...but yesterday I installed a complete turbo-back 3 inch. exhaust and removed the cat. I heard that going with a "straight pipe" setup your boost will increase automatically do to less restriction, is this true??

right now I don't have and "accurate" boost gauge so I don't want to break my turbo...

any help would be great, thanks.

joel w · 11-29-2005, 06:42 PM

i just upgraded my turbo back to 3" and yes it upped my boost a few lbs.. might be a good idea so as not to over spin the ct26...

skunk · 11-29-2005, 08:20 PM

I shimed my waste gate and run a straight through exaust I think you will be fine you will only hit max boost running at high speeds, 12 psi is fuel cut, so i would just work of that, play with it if you hit fuel cut, back off a little, and you really cant break the turbo doing what your talking about, the ct26 is more than capable of pushing 14 to 15 psi stock

joel w · 11-29-2005, 10:09 PM

thats what i used to think before i toasted 2 turbos and did the research.. anything over 13psi will only create heat and overspin it.. it will not flow anymore air over 13... check it out...

skunk · 11-30-2005, 04:10 AM

yeah...i thought it was any thing over 15, but your probly rite...my point was that he would hit fuel cut before any thing could happen, correct me if im wrong.

joel w · 11-30-2005, 04:25 AM

ya fuel cut is 14.5 i think? the ct-26 can make 20psi but it wont last long at all..
As i was told by several turbo makers/rebuilders that at 13psi, the ct-26 is at its max for airflow and is spinning way too fast even at 13psi. most say that its under sized even at 8 psi. so there is no gain from 13-15psi.. only heat is created which really means less power.. hope this helps.. most people suggest 9 or 10 psi on the stock. im running with a 50 trim upgrade and people still tell me to keep it under 11psi..

anyone agree or disagree here?

sakara · 11-30-2005, 05:43 AM

the all tracs also have the ct26 turbo... They will boost to 14-15 safely... anything higher then that running constantly and u can risk the big boom, lol.

skunk · 11-30-2005, 06:23 AM

thanks. because i was under the influence that i could boost more. I have an 88 alltrac( striped bare ready to build into a beast ) I will keep that in mind, it seems were all on the same page

SupraMan1784 · 11-30-2005, 02:20 PM

i suggest leaving the 26 under 14 psi, as jwills said he toasted two turbos, teh 3'' should increase your flow as long as it continues all the way to the back and it will create a little more boost....joel man its tough in this forum cause everyone mainly has a 7m....i like hanging around in teh other forum where they got a bunch of 1jzs and a dude with a 2jz...there is more fun, here is a little more technical

lifesnotfair · 11-30-2005, 03:16 PM

What other forum? MKIV or what?

11-29-2005, 06:33 PM	#1
87sleeper Stock Join Date: Oct 2005 Location: Chula Vista, CA Posts: 14	will my ct-26 blow if I don't turn down boost? hi, i'm new to the forum and modding my supra...I recently shimmed my wastegate (link form supra_girl I believe) with 4 washers, that gives me about 9psi...but yesterday I installed a complete turbo-back 3 inch. exhaust and removed the cat. I heard that going with a "straight pipe" setup your boost will increase automatically do to less restriction, is this true?? right now I don't have and "accurate" boost gauge so I don't want to break my turbo... any help would be great, thanks.

11-29-2005, 08:20 PM	#3
skunk 3" Exhaust Join Date: Jun 2005 Location: southern oregon Posts: 133	14 psi I shimed my waste gate and run a straight through exaust I think you will be fine you will only hit max boost running at high speeds, 12 psi is fuel cut, so i would just work of that, play with it if you hit fuel cut, back off a little, and you really cant break the turbo doing what your talking about, the ct26 is more than capable of pushing 14 to 15 psi stock

11-30-2005, 04:10 AM	#5
skunk 3" Exhaust Join Date: Jun 2005 Location: southern oregon Posts: 133	yeah yeah...i thought it was any thing over 15, but your probly rite...my point was that he would hit fuel cut before any thing could happen, correct me if im wrong.

11-30-2005, 04:25 AM	#6
joel w Lexus & 550's Join Date: Aug 2005 Location: In the shadows Posts: 506	ya fuel cut is 14.5 i think? the ct-26 can make 20psi but it wont last long at all.. As i was told by several turbo makers/rebuilders that at 13psi, the ct-26 is at its max for airflow and is spinning way too fast even at 13psi. most say that its under sized even at 8 psi. so there is no gain from 13-15psi.. only heat is created which really means less power.. hope this helps.. most people suggest 9 or 10 psi on the stock. im running with a 50 trim upgrade and people still tell me to keep it under 11psi.. anyone agree or disagree here? Last edited by joel williams; 11-30-2005 at 05:20 AM. Reason: better

11-30-2005, 05:43 AM	#7
sakara Intake Join Date: Nov 2005 Location: PA Posts: 35	the all tracs also have the ct26 turbo... They will boost to 14-15 safely... anything higher then that running constantly and u can risk the big boom, lol. __________________

11-29-2005, 06:42 PM	#2
joel w Lexus & 550's Join Date: Aug 2005 Location: In the shadows Posts: 506	i just upgraded my turbo back to 3" and yes it upped my boost a few lbs.. might be a good idea so as not to over spin the ct26...

11-29-2005, 10:09 PM	#4
joel w Lexus & 550's Join Date: Aug 2005 Location: In the shadows Posts: 506	thats what i used to think before i toasted 2 turbos and did the research.. anything over 13psi will only create heat and overspin it.. it will not flow anymore air over 13... check it out...

11-30-2005, 06:23 AM	#8
skunk 3" Exhaust Join Date: Jun 2005 Location: southern oregon Posts: 133	thanks. because i was under the influence that i could boost more. I have an 88 alltrac( striped bare ready to build into a beast ) I will keep that in mind, it seems were all on the same page

11-30-2005, 02:20 PM	#9
SupraMan1784 SP58GT Join Date: Jun 2005 Location: Dirty Jerz Posts: 691	i suggest leaving the 26 under 14 psi, as jwills said he toasted two turbos, teh 3'' should increase your flow as long as it continues all the way to the back and it will create a little more boost....joel man its tough in this forum cause everyone mainly has a 7m....i like hanging around in teh other forum where they got a bunch of 1jzs and a dude with a 2jz...there is more fun, here is a little more technical __________________ Now: Saving for an MKIV Broken Rides: (Sold) 91 supra turbo 5speed with a 1jzgte motor 421whp 400(399) ft*lbs of torque on tap @ 15 psi "Always outnumbered, never outgunned."

11-30-2005, 03:16 PM	#10
lifesnotfair 3" Exhaust Join Date: Oct 2005 Posts: 169	Hrm... What other forum? MKIV or what?

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