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The Truth about RX Turbo Fuel Injector Flow Rates

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hmm maybe i will try myx's flowed injector rating on my rx's fuel table and see how well it likes it ..

i have mine set for 80 cc a min on my megasquirt setup and it seems to run pretty good for a tired old motor

 

edit: my one key is borked .. so make that one eighty cc's

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some guy in new zealand fitted 1983 jaguar xj6 injectors into his rx.they fit straight in with a change of o-ring.possum Borne used these in his rx rally car in the day.

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btw according to a fuel psi conversion utiliity for one of my megasquirt tuneing programs

240 cc/min at 43psi converts to

219 cc/min at 36 stock suby psi

 

now i assume the 36 psi we are supposed to get is only at idle ect

or is that the max full boost fuel psi the regulator provides? since that might be useful to know

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btw according to a fuel psi conversion utiliity for one of my megasquirt tuneing programs

240 cc/min at 43psi converts to

219 cc/min at 36 stock suby psi

 

now i assume the 36 psi we are supposed to get is only at idle ect

or is that the max full boost fuel psi the regulator provides? since that might be useful to know

 

Clayton, the Fuel Pressure regulator doesn't regulate at a straight 36 psi.

 

The regulator is setup to deliver a steady 36(point something) PSI above manifold pressure.

 

ergo, at 10 psi of boost, you should be seeing 46psi at the injectors

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The Subaru regulators should be 36psi at atmospheric. Under vacuum the pressure should drop, and conversely rise under boost. I still have my megasquirt set to 185, although 219 would be the proper number given the test results as Clayton said. A regulator from a 42psi car would be an upgrade in addition to fuel management, giving you the maximum from the stock injectors.

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wel if i tell ms my injectors are much bigger than 200 cc then it starts to bog down even at idle

and this is with stock xt spider non turbo injectors on a turbo rx.. so go figure

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Clayton, the Fuel Pressure regulator doesn't regulate at a straight 36 psi.

 

The regulator is setup to deliver a steady 36(point something) PSI above manifold pressure.

 

ergo, at 10 psi of boost, you should be seeing 46psi at the injectors

thats kinda what i wanted to know is the when and where the max psi occured at

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Just got mine back from RC. Injectors from an 88 RX. #1 and #3 might be switched, but #2 and #4 are the correct cylinders.

rc_full_sheet_bw.jpg

 

Off of what car, year, model are these injector flow rates in reference too?

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So I got my RX injectors back from RC engineering. The results were good. Interesting to look at the before and after picture

 

Picture023.jpg

 

you can see the cleaned on the right. The gap is wider, and they all came back a different color? wierd

 

off my donor engine never actually ran in my rx:

before/ after

221--Dripping/ 238 exc

230--good /240-exc

235--good /242-exc

1 with electrical damage

 

replaced with injector from car

220--good /240-exc

 

Interesting how the one that was actually on my car, had a good spray pattern but, the worst cc/min

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