scoob bhp and cc injectors's 740cc your aving a laugh
24 January 2002, 04:34 PM
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I heard that you need 740cc injectors to make a 2.0 scoob hit 340bhp......
Could somebody tell me why ??
cossie makes 340 on 382cc injectors...
Mine is 400+ on 437cc injectors....
Surely 740cc on a 2.0l engine will give some serious borewash and cause you to need an oil changed about every week, because of the petrol content in the oil..
I know you don't because Craig's is 360 on standard injectors...
Can someone explain why 740 is required.. ???
Apart from ESSO or shell
Could somebody tell me why ??
cossie makes 340 on 382cc injectors...
Mine is 400+ on 437cc injectors....
Surely 740cc on a 2.0l engine will give some serious borewash and cause you to need an oil changed about every week, because of the petrol content in the oil..
I know you don't because Craig's is 360 on standard injectors...
Can someone explain why 740 is required.. ???
Apart from ESSO or shell
24 January 2002, 04:46 PM
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Yeah, but surely a cc is measured the same...
Unless a cossie just use's them to the max (properly) cause the pectal can map then better...dunno
Could it be the spray pattern.
Unless a cossie just use's them to the max (properly) cause the pectal can map then better...dunno
Could it be the spray pattern.
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24 January 2002, 05:30 PM
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>>Although mine wasn't fine till the fuel pump was upgraded
I just hope people notice this little comment ... now why is it that my fuel pump is being uprated as we speak, and that my car will run 1.3 bar boost (VF23) with 75 % injector duty cycle at 7000 RPM ?
I was *so* amazed as to how much difference the fuel pump really makes (MY99 in my case)
I just hope people notice this little comment ... now why is it that my fuel pump is being uprated as we speak, and that my car will run 1.3 bar boost (VF23) with 75 % injector duty cycle at 7000 RPM ?
I was *so* amazed as to how much difference the fuel pump really makes (MY99 in my case)
24 January 2002, 06:41 PM
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Craig ... well, I only tend to trust my eyes these days ... as you may now, I'm using a Unichip and a VF23 on a MY99.
With standard pump, we had to enrich the mixture seriously at top end (1 bar at 7000 RPM). OK, nice 9 % CO values & all that, so no problem. Everyone happy.
Until the bloke who works on my car ordered an uprated fuel pump ... we now have to *lean* out the mixture via the Unichip. Exactly same setup, just with other fuel pump. Amazing as I said.
The 440 cc injectors can flow a lot, provided the fuel pump can follow (and no, it's got nothing to do with fuel pressure).
Also, it's got nothing to do with half empty fuel thanks, in case you wondered
With standard pump, we had to enrich the mixture seriously at top end (1 bar at 7000 RPM). OK, nice 9 % CO values & all that, so no problem. Everyone happy.
Until the bloke who works on my car ordered an uprated fuel pump ... we now have to *lean* out the mixture via the Unichip. Exactly same setup, just with other fuel pump. Amazing as I said.
The 440 cc injectors can flow a lot, provided the fuel pump can follow (and no, it's got nothing to do with fuel pressure).
Also, it's got nothing to do with half empty fuel thanks, in case you wondered
24 January 2002, 06:43 PM
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Subaru and cossy injectors are measured differently, IIRC. The flow rate is measured at X duty cycle and Y fuel pressure, IIRC, and the base X and Y values are different for cossy and subaru injector flow figures.
I'm fairly sure you can expect a fair bit more than 400bhp from 740cc injectors on a subaru, assuming, of course, everything else is uprated accordingly.
I'm fairly sure you can expect a fair bit more than 400bhp from 740cc injectors on a subaru, assuming, of course, everything else is uprated accordingly.
24 January 2002, 09:10 PM
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There certainly seems to an annomoly, when it comes to injector sizing on the Subaru.
Firstly, there are two methods for "sizing" injectors.
1) Static: flow measured with injector wide open.
2) Dynamic: flow measured at 3bar, at 80% idc.
I suspect that the Subaru injectors are measured "static", and the majority are measured "dynamically".
This would mean that the Cossie 382cc injector would equate to a 477cc injector in "Subaru" terms. I could be VERY wrong though
IMO, there is NO WAY the "Subaru" 380cc injector can "safely" run 345bhp.
Andy, what IDC's were you getting at 356bhp, and you did have 440cc injectors.
I have no idea what power my STi was producing, but the Motec showed the 550cc's were maxing out, running .86/.87 lambda voltage.
Just to make you happy Steve, I now run Cossie greens
Mark.
Firstly, there are two methods for "sizing" injectors.
1) Static: flow measured with injector wide open.
2) Dynamic: flow measured at 3bar, at 80% idc.
I suspect that the Subaru injectors are measured "static", and the majority are measured "dynamically".
This would mean that the Cossie 382cc injector would equate to a 477cc injector in "Subaru" terms. I could be VERY wrong though
IMO, there is NO WAY the "Subaru" 380cc injector can "safely" run 345bhp.
Andy, what IDC's were you getting at 356bhp, and you did have 440cc injectors.
I have no idea what power my STi was producing, but the Motec showed the 550cc's were maxing out, running .86/.87 lambda voltage.
Just to make you happy Steve, I now run Cossie greens
Mark.
24 January 2002, 09:14 PM
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Mark,
You know my injector duty cycle was at 100% at 6000rpm, as I have mentioned this before!
That's why I had 550cc injectors and an uprated fuel pump ready to be installed, until I decided to sell my car.
Andy
Ps - Unused Power Enterprise fuel pump for sale!
You know my injector duty cycle was at 100% at 6000rpm, as I have mentioned this before!
That's why I had 550cc injectors and an uprated fuel pump ready to be installed, until I decided to sell my car.
Andy
Ps - Unused Power Enterprise fuel pump for sale!
24 January 2002, 11:20 PM
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Cheers for the Info, i thought there must be a miss somewhere...
I mean 740, 8 greens gives 760 ish and makes 550bhp
I thought the scoob injectors must be different deep down, would be nice to know for defo tho
I mean 740, 8 greens gives 760 ish and makes 550bhp
I thought the scoob injectors must be different deep down, would be nice to know for defo tho
24 January 2002, 11:47 PM
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Dingy,
I guess you must be referring to certain cars on here.
The honest answer is that I don't know the underlying reason - although I think Mark has a point.
What I do know from experience is that the 740 injectors do make the car run much better - power delivery is smoother. Also your comments about bore wash don't make much sense - if the car is mapped to the correct Lambda values across the rev range then where would the surplus fuel be.
All I know is that with 440inj and a Link - I had 130% 'duty cycle' as reported by the Link.
What all of these cars have in common, including Mark's Motec car - is that the mapping philosophy is from the same source. What I don't know is how much Link tuners have played with the Master Fuel - which seems to set the base for the Injector pulse width. It maybe with a significantly higher Master then the duty cycle would fall - however then the mapping granularity would be poor.
So what conclusion would I draw - the modus operandi of the Link may well lead to overspecced injectors which have different compromises.
All this is suppostion except that my car runs much better and smoother on 740s, with appropriate Lambda targets across the rev range, including idle (although idle is only just!).
So is this a weakness of Link tuning philosophy - possibly.
BTW - before water injection the 740inj showed 74% duty cycle on the Link - there are rumours of a Link car running 80% duty cycle. Although this must vary - as another car the same as mine was running 76% duty cycle and had 30bhp less than my car.
Trout
I guess you must be referring to certain cars on here.
The honest answer is that I don't know the underlying reason - although I think Mark has a point.
What I do know from experience is that the 740 injectors do make the car run much better - power delivery is smoother. Also your comments about bore wash don't make much sense - if the car is mapped to the correct Lambda values across the rev range then where would the surplus fuel be.
All I know is that with 440inj and a Link - I had 130% 'duty cycle' as reported by the Link.
What all of these cars have in common, including Mark's Motec car - is that the mapping philosophy is from the same source. What I don't know is how much Link tuners have played with the Master Fuel - which seems to set the base for the Injector pulse width. It maybe with a significantly higher Master then the duty cycle would fall - however then the mapping granularity would be poor.
So what conclusion would I draw - the modus operandi of the Link may well lead to overspecced injectors which have different compromises.
All this is suppostion except that my car runs much better and smoother on 740s, with appropriate Lambda targets across the rev range, including idle (although idle is only just!).
So is this a weakness of Link tuning philosophy - possibly.
BTW - before water injection the 740inj showed 74% duty cycle on the Link - there are rumours of a Link car running 80% duty cycle. Although this must vary - as another car the same as mine was running 76% duty cycle and had 30bhp less than my car.
Trout
25 January 2002, 12:59 AM
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Steve,
I think Trout is saying, that with WI, you actually reduce the fueling, and therefore the idc's would drop.
Andy, sorry mate, but at my age the memory is going. I just felt that your post "read" as if 440's were ok to run 356bhp. As you know, the Link only shows a max of 100% on the tuning module, although the data log goes much higher. IIRC Bob had readings in excess of 120%, and I guess you'd have been pretty close to that running 7500rpm +, and 356bhp
Mark.
I think Trout is saying, that with WI, you actually reduce the fueling, and therefore the idc's would drop.
Andy, sorry mate, but at my age the memory is going. I just felt that your post "read" as if 440's were ok to run 356bhp. As you know, the Link only shows a max of 100% on the tuning module, although the data log goes much higher. IIRC Bob had readings in excess of 120%, and I guess you'd have been pretty close to that running 7500rpm +, and 356bhp
Mark.
25 January 2002, 08:34 AM
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You reduce fueling with WI, bit silly that don't you think ???
WI as far as i see it is a good safety measure to keep the ACT's low, around 40 degree's for optimal running and performance.
So it comes on about 42 and goes off at 38 degrees kind of thing, altering fueling at this point is a BAD idea.....that for sure would have cost me 3 engines because I have Had 3 ERL race pumps pack up on me...
Please explain why you would alter the fueling because of the WI and know this is not the topic but is also interesting.
Trout, Not meaning any car on here,(but they could be on here, dunno), just heard this figure injector mentioned on several occasions now and couldn't get my head round it.
WI as far as i see it is a good safety measure to keep the ACT's low, around 40 degree's for optimal running and performance.
So it comes on about 42 and goes off at 38 degrees kind of thing, altering fueling at this point is a BAD idea.....that for sure would have cost me 3 engines because I have Had 3 ERL race pumps pack up on me...
Please explain why you would alter the fueling because of the WI and know this is not the topic but is also interesting.
Trout, Not meaning any car on here,(but they could be on here, dunno), just heard this figure injector mentioned on several occasions now and couldn't get my head round it.
25 January 2002, 11:07 AM
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steve, have said before, main goal of water injection is to reduce det by evaporating in combustion chamber, not by lowering charge temps, it has that effect too, but it is better use of water for it to stay as water until as close to compression stropke as possible. water spray is more effective at cooling as it allows the heat energy of the air to evaporate away from the fins of the intercooler.
25 January 2002, 11:13 AM
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Tried Water spray on my car with 3 Gauges for the temp...
MADE ZERO difference and i got the same cr@p intercooler as you.
I get what you are saying, but my car doesn't det without the WI so not needed in that respect.
MADE ZERO difference and i got the same cr@p intercooler as you.
I get what you are saying, but my car doesn't det without the WI so not needed in that respect.
25 January 2002, 01:37 PM
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Dingy,
given the nature of your posts I am somewhat taken aback that you are not aware of the impact of water injection on the CO readings.
Simply when you put water in the CO readings rise dramatically - therefore less fuel is needed.
Yeah, before WI my car didn't det, but with WI I can significantly increase advance and so get more power.
If the water injection fails - as it did recently (for an unrelated reason) then a combination of having knock control on the Link, EGT, a lambda link, knock link and a knock count display all on the dashboard ensured that I had now worries at all. Indeed, only with sustained high level running - such as on track - would have led to any problems.
Oh, and just out of interest the IDC reduced by 3% with the introduction of water - a significant difference.
The other point I would make - even the the car is ostensibly leaner, on track the sort of peak map that can be used on road will also stand up to track work as the heat soak is much better controlled by having water - in-cylinder cooling has many advantages!
Trout
PS My comment regarding cars with 340+ and 740 injectors does seem quite specific - I only know of one that has been 'published' in any way and of two others that are running this kind of config - although there are a number of cars with 740s - only a handful have had these figures.
given the nature of your posts I am somewhat taken aback that you are not aware of the impact of water injection on the CO readings.
Simply when you put water in the CO readings rise dramatically - therefore less fuel is needed.
Yeah, before WI my car didn't det, but with WI I can significantly increase advance and so get more power.
If the water injection fails - as it did recently (for an unrelated reason) then a combination of having knock control on the Link, EGT, a lambda link, knock link and a knock count display all on the dashboard ensured that I had now worries at all. Indeed, only with sustained high level running - such as on track - would have led to any problems.
Oh, and just out of interest the IDC reduced by 3% with the introduction of water - a significant difference.
The other point I would make - even the the car is ostensibly leaner, on track the sort of peak map that can be used on road will also stand up to track work as the heat soak is much better controlled by having water - in-cylinder cooling has many advantages!
Trout
PS My comment regarding cars with 340+ and 740 injectors does seem quite specific - I only know of one that has been 'published' in any way and of two others that are running this kind of config - although there are a number of cars with 740s - only a handful have had these figures.
25 January 2002, 01:52 PM
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Trout i get it.
I have an EGT, wouldn't trust any air/fuel ratio meter unless it cost about 2k like Ahmed's..
As for the Knock link it picks up det when there aint any...
So you are saying you can monitor all these gauges whilst driving flat out...
Sorry but my car is way too fast to keep an eye on all those things whilst driving, and the risk far out ways the advantage....
I have an EGT, wouldn't trust any air/fuel ratio meter unless it cost about 2k like Ahmed's..
As for the Knock link it picks up det when there aint any...
So you are saying you can monitor all these gauges whilst driving flat out...
Sorry but my car is way too fast to keep an eye on all those things whilst driving, and the risk far out ways the advantage....
25 January 2002, 03:03 PM
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I think i need to take you out in my car trout just to show you..
Steering - non power assisted
Brakes - mmmmmm like some
RWD so most of the time you are looking out the side windows, and lights aren't visable.
0-100 in 9.5 secs but with a 0-60 of 5.3, compared to CraigH's time of 3.7 to 60 and the same 0-100 i guess you can see what i mean.
The car is very nervous also which don't aid the view of loads of flashing lights.
Steering - non power assisted
Brakes - mmmmmm like some
RWD so most of the time you are looking out the side windows, and lights aren't visable.
0-100 in 9.5 secs but with a 0-60 of 5.3, compared to CraigH's time of 3.7 to 60 and the same 0-100 i guess you can see what i mean.
The car is very nervous also which don't aid the view of loads of flashing lights.