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What is your max PSI on stock turbo?

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#1
Hi all, I’m curious what the highest PSI you’re producing on a stock turbo - both engine modded and stock.

I’ll go first. I’m not sure if this is the absolute highest but it’s the highest I’ve recorded:

Max PSI - 27.22

List of mods I have done to my car:

Whoosh V3 intercooler
Whoosh intercooler hose replacements (including J pipe)
Whoosh symposer delete
Ramair induction hose
Ramair crossover pipe
Go Fast Bits DV+
Cobb drop-in filter
Radium Engineering oil catch can (PCV side)
Whoosh short shifter
Whoosh transmission cables aluminum bushings
Whoosh shifter base aluminum bushings
Whoosh race spec rear motor mount
Vibra-Technics uprated passenger side engine mount
Vibra-Technics prated transmission mount
Cobb Accessport V3 with Dizzy E30 and 93 tune
StopTech slotted rotors - front and rear
EBC Orange Stuff brake pads - front and rear
Whoosh stainless steel braided brake lines


I am currently running Dizzy’s stage 2 - 93 octane tune. I have his e30 tune but e85 is hard to come by in Pittsburgh.
 


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OP
Wolfsbora
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Thread Starter #7
Just as a reference point, I was told by Ford Performance that the FiST will boost to a maximum of 22 PSI stock.
Yes..I’ve seen it exceed 22 PSI, though. Happened with my setup a few times. Nothing crazy. Only in the 23 range but there are definitely exceptions.
 


gtx3076

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#8
25 is usually the most I'll see. If it's really cold and I'm in high gear I might see 26.
 


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#13
Not raining on your parade, but record datalog to see what psi your current tune/mods trully can hold. The max shown on AP monitor is usually the momentary boost spikes between shifts.

I use the max monitor as an early indicator of possible boost leak over time by comparing it to the last time I ran the car hard…
 


Last edited:
OP
Wolfsbora
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Thread Starter #14
I don’t remember if Jason uses the stage 1 2 3 terminology but I don’t have an upgraded intercooler or radiator so per Cobb it’s considered stage 1
Yes, that’s how I understand it.

Not raining on your parade, but record datalog to see what psi your current tune/mods trully can hold. The max shown on AP monitor is usually the momentary boost spikes between shifts.

I use the max monitor as an early indicator of possible boost leak over time by comparing it to the last time I ran the car hard…
I am pretty confident it is just the spike but still a fun number to compare. I’ll definitely try what you’re suggesting.
 


XR650R

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#16
Just over 26 on my conservative tune.
 




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