Do I need a FPR? or a better map?
#1
Do I need a FPR? or a better map?
The Setup:
99 Miata
Symptom: in 2nd once I get to about 4k rpm 5psi ish my afr drops off and the engine starts to cut out, in 3rd it's the same unless I slowly roll on the throttle then it pulls like a effin monster but afr is low @ 10.2.
I have solved all boost leak issues
Plugs are set at 30
Do I need COPS?
A tune shop I called said that I need an FPR, but I thought the xede was supposed to take care of that
images of the map soon to follow
99 Miata
- Built motor
- FM head
- TD05-18G turbo - SR20DET hotsidestyle flange
- RC-550 injectors
- Ebay IC
- 14psi
Symptom: in 2nd once I get to about 4k rpm 5psi ish my afr drops off and the engine starts to cut out, in 3rd it's the same unless I slowly roll on the throttle then it pulls like a effin monster but afr is low @ 10.2.
I have solved all boost leak issues
Plugs are set at 30
Do I need COPS?
A tune shop I called said that I need an FPR, but I thought the xede was supposed to take care of that
images of the map soon to follow
#4
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This is discussion from the first thread I started on MT (other than my intro) asking about what sized injectors I needed for 250hp in an NB with the stock fuel pressure regulator:
No. What you're missing is that the pressure in the injectors has to fight against the pressure in the manifold in order to spray fuel. NAs have a fuel pressure regulator which is relative to the manifold pressure, so as MAP goes up 1psi, the fuel pressure goes up 1psi to match. NBs don't, they have a constant pressure, so when running 15 psi of boost, the rail is effectively 15 psi lower than is when running WOT when naturally aspirated.
265 rwhp on my NB with stock pump and 550cc RCs, and the stock pump was the limit. I put the 255 walbro in, but haven't been back to the dyno since.
As for the 255 overpowering the stock FPR -- FM says that's known to be an issue when using it on an NA, but that NB regulators are usually fine.
--Ian
265 rwhp on my NB with stock pump and 550cc RCs, and the stock pump was the limit. I put the 255 walbro in, but haven't been back to the dyno since.
As for the 255 overpowering the stock FPR -- FM says that's known to be an issue when using it on an NA, but that NB regulators are usually fine.
--Ian
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Mikel
MEGAsquirt
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09-28-2015 04:46 PM