850cc Injectors for less than 400 bhp
19 July 2003, 09:29 PM
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550's get into high duty cycles when reaching 400 bhp.
Looking for a comfort zone and thinking about 850's, but would have to run them at about 55%.
Will that be safe and easy to map?
Looking for a comfort zone and thinking about 850's, but would have to run them at about 55%.
Will that be safe and easy to map?
19 July 2003, 10:09 PM
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LOL @ Andy 
Thanks John, looks like I've bought injectors that are not suitable for my engine's spec, ****
If anyone wants to buy them or swap for 650's (750's?)get in touch.
Would I get away with 750's John if I cant get 650's?
Thanks John, looks like I've bought injectors that are not suitable for my engine's spec, ****
If anyone wants to buy them or swap for 650's (750's?)get in touch.
Would I get away with 750's John if I cant get 650's?
20 July 2003, 10:26 PM
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550s at what pressure? Idle's beginning to get 'interesting' at 4 bar 
I'm getting a jump from 13.2AFR to a not very happy 16.5 with the tiddliest fuel change I can do.
My rather iffy calcs suggest that 550s should be fine at 420ish - for rather brief periods - at 3.8 bar. But I'm not convinced, as I have no idea what pressure the 550s are usually measured at as being at 550...
I'm getting a jump from 13.2AFR to a not very happy 16.5 with the tiddliest fuel change I can do.My rather iffy calcs suggest that 550s should be fine at 420ish - for rather brief periods - at 3.8 bar. But I'm not convinced, as I have no idea what pressure the 550s are usually measured at as being at 550...
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20 July 2003, 11:48 PM
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I ran my 550's at 3.8 bar and made 440 bhp.
I could still hold a nice rich AFR of 10.8:1 whilst running flat out at over 170 mph at Elvington last weekend.
Depending on the actual efficiency of your engine, you could use much more fuel and achieve less power output.
The biggest players in this equation on the Subaru are the turbo and exhaust system.
For example if your turbo is innefficient, you will build a high exhaust backpressure. This will reduce the engine output but will still require fuel and air to overcome the pumping losses.
It's not so easy as saying xxx injectors are good for yyy bhp
Andy
I could still hold a nice rich AFR of 10.8:1 whilst running flat out at over 170 mph at Elvington last weekend.
Depending on the actual efficiency of your engine, you could use much more fuel and achieve less power output.
The biggest players in this equation on the Subaru are the turbo and exhaust system.
For example if your turbo is innefficient, you will build a high exhaust backpressure. This will reduce the engine output but will still require fuel and air to overcome the pumping losses.
It's not so easy as saying xxx injectors are good for yyy bhp
Andy
21 July 2003, 12:13 AM
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Could possibly lay my hands on a set of 550's
Don't know why I never went for them to start with
If anyones interested in the 850's drop me an e-mail.
£350, they are cleaned and tested with new o-rings and pintle caps.
Or will swap for 550's, 650's or 740's
Don't know why I never went for them to start with
If anyones interested in the 850's drop me an e-mail.
£350, they are cleaned and tested with new o-rings and pintle caps.
Or will swap for 550's, 650's or 740's
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