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Discussion Starter · #1 ·
Hey Guys,

What kind of power (Max.) can be made on 105 octane?
I know their are a few variables that can affect this, but if their's anyone
that has made big power on octane this high (or fairly similar), please give your input.
 

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I ran 26-28 PSI on a T-64 for a couple years on Sunoco GT Plus (99 MON, 104 R+M/2) and then when I pulled the head to port it there was NO sign of detonation whatsoever. Then a couple years later I did a compression test and the numbers were still in the 170 PSI range across all cylinders (very upper end of the specifications). I say all this to preface my belief that you can run that kind of boost on the factory ECU with a good unleaded fuel.

As far as what power, I later made 682 whp (Dynojet) on ~24 PSI (on an SP74 with headwork and 264s, and some mix of unleaded and leaded fuel).
 

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Im running 25psi all the time on my car..

Also Im on 98 RON.. UK and US fuel grading is different though so I have no idea what that is in US octane levels..
 

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Discussion Starter · #5 · (Edited)
TRD3000 said:
Im running 25psi all the time on my car..

Also Im on 98 RON.. UK and US fuel grading is different though so I have no idea what that is in US octane levels..
I think 98 RON works out to be 93 here in the U.S. But what kind of turbo are you running 25psi on?
 

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SHOMSPEED said:
I think 98 RON works out to be 93 here the US. But what kind of turbo are you running 25psi on?
71 GTS
 

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No.


The S trim has a different hot side.

Same spool and a little more power...
 

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TRD3000 said:
Im running 25psi all the time on my car..

Also Im on 98 RON.. UK and US fuel grading is different though so I have no idea what that is in US octane levels..
Stock ECU or standalone?
 

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I'm sure it depends on various factors including the tune, and maybe I'm overly conservative, but I always thought going to 25psi on 98 RON is risky for most setups. I cut the data below from this link http://www.btinternet.com/~madmole/Reference/RONMONPON.html which equates 98 RON to about our 94 PON rated pump octane and 25psi is too high for our 94 pump.


RON MON PON
90 83 86.6
92 85 88.5
95 87 91
96 88 92
98 90 94
100 91.5 95.8
105 95 100
110 99 104.5
 

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There are three of us in the Uk who have recently had Motecs installed.

2 of them are the M600's and Im running a Motec M800

Compared to the other two Im being conservative with my boost.. We have all been tuned to 2 bar and I turned mine down to 1.4.

The other two are running a constant 1.6- 1.8 and we are not having any problems with knock /det at all.

I had my head romoved after 8 months of 25 psi and the pistons were looking very well :bigthumb:

Anyway.. Im a VVTI so my cam profiles are very different to most and they are ever changing.
 
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