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?

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

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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...