MR2 boost cut

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MR2 boost cut

Postby touge rolla » Thu Mar 08, 2007 7:26 pm

tiring of driving a nisssan bluebird whilst waiting for my ever so slowly progressing corolla project i went and bought myself a 1990 MR2 GT. It has had the exhaust done and I've put a K&N pod filter in and a Gizzmo IBC. A sard fuel pressure regulator should be in very soon. now i want to remove the boost/fuel cut, don't worry i don't plan on turning the boost up to any thing too high. I've heard a few theories on how to do this from crossing wires on the plug to simply unplugging it.
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Postby solitaire » Thu Mar 08, 2007 7:33 pm

there are plenty of posts on mr20oc.com and i think mr2.org.nz to help you make a circuit to up the fuel cut a few psi...

best to up it to 16 than to get rid of it all together bro... might save your engine one day :wink:
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Postby Dell'Orto » Thu Mar 08, 2007 9:13 pm

Just unplug the hose from the boost pressure sensor and block it off, that disables it. Don't bother going higher than 15psi on the CT26
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Postby Crampy » Thu Mar 08, 2007 9:25 pm

If you do unplug the boost pressure sensor, can I have it?

They're just a normal MAP sensor aye, but is used to power the boost gauge and boost cut?
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Postby solitaire » Thu Mar 08, 2007 9:55 pm

Mmm, Boost wrote:Just unplug the hose from the boost pressure sensor and block it off, that disables it. Don't bother going higher than 15psi on the CT26

Aggreed...

while there are obviosly other factors involved i only got 5kws from upping the boost from 8 to 11... i didnt feel anything much when i upped it to 13 for an afternoon...

I know its a hotly contested topic but in my humble opinion 11odd psi is about as good as it gets... i think any more would put the turbo stress/power ratio into unbalance...

feel free to correct me all you techie people :D
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Postby Dell'Orto » Thu Mar 08, 2007 10:09 pm

IIRC, I gained 20kw going from 10 to 15, but I reckon the majority would have been made with about 3psi.
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Postby avinesh » Fri Mar 09, 2007 6:19 pm

Mmm, Boost wrote:IIRC, I gained 20kw going from 10 to 15, but I reckon the majority would have been made with about 3psi.


was this on a ct26???
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Postby Dell'Orto » Fri Mar 09, 2007 6:43 pm

Yup.
Edit: Ah, found graph - was 20hp, not KW. After thinking about it I thought that sounded a bit high.
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Postby touge rolla » Tue Mar 13, 2007 11:19 pm

thanks, got highest setting on 1bar (14.5psi) goes a lot harder.
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Postby solitaire » Wed Mar 14, 2007 8:59 am

Mmm, Boost wrote:Yup.
Edit: Ah, found graph - was 20hp, not KW. After thinking about it I thought that sounded a bit high.


Where you on a ct26 mate?

Ive heard stories about compressor wheels shattering above 12psi
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Postby sergei » Wed Mar 14, 2007 9:05 am

I don't know about CT26 but there is a huge difference between 0.5bar and 1bar on a "CT20b"... Although I don't have any performance figure, I am just judging from how fast it goes from 80 to 110... Actually it is difference between 15 sec and low 13sec quarter mile run.
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Postby vvega » Wed Mar 14, 2007 1:51 pm

solitaire wrote:
Mmm, Boost wrote:Yup.
Edit: Ah, found graph - was 20hp, not KW. After thinking about it I thought that sounded a bit high.


Where you on a ct26 mate?

Ive heard stories about compressor wheels shattering above 12psi


even first hand info is only as good as the persona telling it ..let alone the person passing it on :d
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Postby solitaire » Wed Mar 14, 2007 1:55 pm

vvega wrote:even first hand info is only as good as the persona telling it ..let alone the person passing it on :d

Which is why i was asking about peoples first hand experiences :wink:
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Postby Dell'Orto » Wed Mar 14, 2007 7:04 pm

solitaire wrote:
Mmm, Boost wrote:Yup.
Edit: Ah, found graph - was 20hp, not KW. After thinking about it I thought that sounded a bit high.


Where you on a ct26 mate?

Ive heard stories about compressor wheels shattering above 12psi


Yep, on a ceramic CT26 and also a steel one. Both took 15psi on a regular basis, without falling apart. Only replaced the turbo cause the filter wasnt filtering :?
There is no rhyme nor reason to CT26's falling apart, they just do.
1988 KE70 Wagon - Slowly rusting
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2018 Ranger - Because workcar
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OMG so shiny!

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Postby solitaire » Wed Mar 14, 2007 7:52 pm

Mmm, Boost wrote:...


Cheers dude :D
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