V7 SLR Posted November 11, 2002 Share Posted November 11, 2002 Well, in theory it is better to use the injectors at the original pressure. Increasing pressure will increase flow, but the pressure increase isn't proportional to the flow increase (might be log or square - don't know). Can't say whether there would be "other component implications" or not in increasing the pressure. The other reason is because it is a bolt on upgrade. The fuel rail and FPR fit nicely, so you don't have to mess about with sourcing an alternative (with the possibility of having to source new pipes and connectors too). The injectors just fit. The software says "What did you have, and what have you now go?". Pop those numbers in and the map recalibrates. Easy as pie. Basically, if mine passes the MoT with the current injectors fitted, I'd say use them. They work. They will continue to work if you reach 250bhp and they're cheap too..!! Then again, what power are you aiming at? Up to 200bhp it's not a problem. More for some people (wondering if I really have the required pressure in mine now, as other people have hit 220bhp on standard injectors). You need to be aware that I have the uprated fuel pump. TO increase flow or pressure you may need such. When I was contemplating this move, plenty of advice was given to me to check this first as it would be required. Worcs L7 club joint AO.//Membership No. 4379//Azure Blue SLR No. 0077//Se7ens List Tours Link to comment Share on other sites More sharing options...
Steve-B Posted November 11, 2002 Share Posted November 11, 2002 For those of us who don't completely understand this thread, and I'm not alone, could someone please summarise the plusses and minuses of this thread. E.G.: 1) duty cycle (I keep thinking about electronics "smoke variables") 2) colours of injectors 3) size of injectors 4) relationship of (1) and (2) to performance It would be a great help to know and understand more about this.. Steve SV VHPD Drive like your wife depended on it.... click here to see our 7 and rallye pictures.... Link to comment Share on other sites More sharing options...
scooby dooby doo Posted November 11, 2002 Share Posted November 11, 2002 So I need to find out wehich fuel pump I have... Where did you source the Saab jobbies and how much were they 🤔 Steve - Duty cycle is the percentage of time the injector is open (and therefore spraying fuel). It obvioulsy can't go above 100. Much over 90 and apparently they start getting unhappy with life.. Colours - seems to be the std way makers differentiate different models of injector, rather than really on a titchy S/N when you want a quick ID. size - how much can it flow when fully open. since an open injector is just a small hole this is measured in volume per time at a given pressure. more pressure gives more flow. HOOPY 500 kg R706KGU Link to comment Share on other sites More sharing options...
V7 SLR Posted November 11, 2002 Share Posted November 11, 2002 Haven't got any details. Think I called Directory Enquiries (Inquiries?) and asked for Neo Brothers Saab breakers. From memory, they only had one such "Neo Bros" in the system. You want injectors from a 2.3 Aero (might want to explain that they are RED). They are 380cc/min, but I doubt the scrappy will know that. It has been suggested that you should get them ultrasonically cleaned. I didn't and they work fine, but I think Mick Smith did. Certainly Rob Walker did (it was he who found Neo Bros and suggested we give them a call). The cost should be about £50, but I think they are a bit more than that (maybe demand has increased after Rob suggested we all give them a call) and with the P&P I ended up about £90 lighter. No matter. I'm very pleased with the results. Unlike what has been suggested, they idle very well, although it is true that granularity is marginal at idle, leading to potential overfuelling (only a problem from the emmissions POV). I'm going to investigate this some more with Emerald next time I'm there. Worcs L7 club joint AO.//Membership No. 4379//Azure Blue SLR No. 0077//Se7ens List Tours Link to comment Share on other sites More sharing options...
Steve-B Posted November 11, 2002 Share Posted November 11, 2002 hoopy, et. al..., what is the proportional theories of an increase in HP relative to size/colour? Steve SV VHPD Drive like your wife depended on it.... click here to see our 7 and rallye pictures.... Link to comment Share on other sites More sharing options...
Peter Carmichael Posted November 11, 2002 Share Posted November 11, 2002 *not happy with life* is not the problem. You can run injectors at 100% - many people suppose they can burn out, but a flow of fuel is an effective way of keeping them cool. Running out of ability to deliver a metered increase in fuel flow is the problem. Not sure whether these diagrams will work, but here goes: Fuel delivery approaching maximum effective duty: __________________ _______________________ ################## /####################### ################### /######################## #################### /######################### #####################____/########################## Getting closer (eight 'blocks' of fuel added): ___________________ ________________________ ##################1 /8####################### ###################2 /7######################## ####################3 /6######################### #####################4__/5########################## Getting closer (eight 'blocks' of fuel added): ____________________ _________________________ ##################*1 /8*####################### ###################*2 /7*######################## ####################*3 /6*######################### #####################*4/5*########################## Last full delivery of increased fuel (eight 'blocks' of fuel added): _____________________ __________________________ ##################**1 /8**####################### ###################**2 /7**######################## ####################**3/6**######################### #####################**45**########################## Reduced increase (six 'blocks' of fuel added): ______________________ ___________________________ ##################***1 /6***####################### ###################***2/5***######################## ####################***34***######################### #####################******########################## Reduced increase (four 'blocks' of fuel added): _______________________ ____________________________ ##################****1/4****####################### ###################****23****######################## ####################********######################### #####################******########################## Reduced increase (two 'blocks' of fuel added) 100% duty _____________________________________________________ ##################*****12*****####################### ###################**********######################## ####################********######################### #####################******########################## Edited by - Peter Carmichael on 11 Nov 2002 13:30:34 Link to comment Share on other sites More sharing options...
Steve-B Posted November 11, 2002 Share Posted November 11, 2002 Peter Excellent ASCII art, but perhaps due to it being Monday I'm a bit dense. Please explain that this means... 🤔 Steve SV VHPD Drive like your wife depended on it.... click here to see our 7 and rallye pictures.... Link to comment Share on other sites More sharing options...
Rob Walker Posted November 11, 2002 Share Posted November 11, 2002 Hoopy, I would caution you in reading too much into the colour of injectors as the various motor manufactures specify different colours and you simply cannot assume, say a green injector will be a high flow type. IMO the optimum injector for a high powered K 210 - 250 bhp is the Bosch 0280 150 420 these are 320 cc/min at 3 bar, have a 23 degree spray angle and are fitted to 1992-1997 Vauxhall Colibra and Vectras Turbo models, and for those colour conseous they are lime green. They are also high impedance and as such are compatable with the Emerald M3D. Rob Link to comment Share on other sites More sharing options...
Nick M Posted November 11, 2002 Author Share Posted November 11, 2002 Well, just spoken to Rob at Pro-Tune and apparently by tweaking the fuel pressure up a little bit the duty cycle has dropped down to between 89 and 93%, which is obviously better than it was. Seeing as I'm unlikely to be searching for more power for a little while I'm going to stick with the Cream injectors for now and will swap them as and when funds (or the wife !) permit the next upgrade. Incidentally, the headline figure was 190bhp at 8,000rpm, which for a 1.6 isn't too shabby I think you'll agree. Link to comment Share on other sites More sharing options...
Rob Walker Posted November 11, 2002 Share Posted November 11, 2002 Nig, The standard fuel pressure is 3 bar nominal. Its likely that your fuel pump is the 19 grams/sec one. IMO this will have to be changed if you are seeking a reliable 230 plus bhp, I swapped mine for the 27 gram/sec JPE pump, this is also fitted to the R500. Now that you have fitted 1227 cams to your high flow head, I do not think you will have a problem with the big SAAB injectors they work perfectly in my engine. I still STRONGLY advise you to have them cleaned and flow checked before you RR/ Map your engine. Its just false economy not to do so, if your engine doesn`t deliver the beans you won`t know where to start looking for the loss of power. Also be aware that the only check you have on mixure is a Lambda probe in the fourth branch of your primaries, if you have a duff/partially blocked injector fitted to 1 2 or 3 you will not see this and you may damage your engine. Edited by - Rob walker on 11 Nov 2002 17:52:00 Link to comment Share on other sites More sharing options...
Peter Carmichael Posted November 11, 2002 Share Posted November 11, 2002 I have done a bit more work on the ASCII stuff and I think I have discovered a few effects that occur as you approach 100% duty cycle. First an explanation of the ASCII art These are the pulses of fuel being injected. ___________ ___________ /########### /########### /############# /############# /############### /############### /#################__________________________________/#################__... Injector open:^--------------^ ^----------------------------------------------------^: Cycle time The # characters represent a volume of fuel injected. The slope at the start and end of injector actuation show that as the injector is opening and closing it delivers some fuel but not the full flow rate of the injector. Duty cycle is the ratio of "injector open" to "cycle time". Note that the "injector open" event starts when the injector starts to open. It ends when the injector starts to close. This is how the ECU controls the injector. The duty cycle increases when the width of the pulse is increased (more throttle opening, more fuel, more torque): ___________________ ___________________ /################### /################### /##################### /##################### /####################### /####################### /#########################__________________________/#########################____... Injector open:^----------------------^ ^----------------------------------------------------^: Cycle time The duty cycle increases when the rate of pulses increases (more revs, more fuel, more power): ___________ ___________ ___________ /########### /########### /########### /############# /############# /############# /############### /############### /############### /#################_________/#################_________/#################_________/... Injector open:^--------------^ ^--------------^ ^--- Cycle time:^---------------------------^---------------------------^--- When the duty cycle gets large (near 100%), the injector has not recovered entirely from the preceding pulse before the next one comes along. This sequence shows the injector open time increasing by the same unit (one dash) each time and the additional fuel delivered is marked up as numerals in the diagram: ___________________ ___________________ ___________________ /################### /################### /################### /##################### /##################### /##################### /####################### /####################### /####################### /#########################_/#########################_/#########################_/... Injector open:^----------------------^ ^----------------------^ ^--- Cycle time:^---------------------------^---------------------------^--- ____________________ ____________________ ____________________ /###################1 /###################1 /###################1 /#####################2 /#####################2 /#####################2 /#######################3 /#######################3 /#######################3 /#########################4/#########################4/#########################4/... Injector open:^-----------------------^ ^-----------------------^ ^--- Cycle time:^---------------------------^---------------------------^--- The last normal increase. One dash extra pulse width results in 4 extra units of fuel being delivered. ______________________ ______________________ ______________________ /8###################*1 /8###################*1 /8###################*1 /7#####################*2 /7#####################*2 /7#####################*2 /6#######################*3/6#######################*3/6#######################*3/ 5#########################*45#########################*45#########################*45... Injector open:^------------------------^ ^------------------------^ ^--- Cycle time:^---------------------------^---------------------------^--- As soon as the open and close events overlap, the next dash of extra pulse width results in 8 units of fuel being delivered, because at the time the opening pulse comes along, the injector is still partially open - it reaches fully open quicker. ________________________ ________________________ ________________________ /6*###################**1 /6*###################**1 /6*###################**1 /5*#####################**2/5*#####################**2/5*#####################**2/ 4*#######################**34*#######################**34*#######################**34 *#########################***#########################***#########################***... Injector open:^-------------------------^ ^-------------------------^ ^--- Cycle time:^---------------------------^---------------------------^--- This effect reduces so that the next dash of pulse width only sees an extra 6 units of fuel. __________________________ __________________________ __________________________ /4**###################***1/4**###################***1/4**###################***1/ 3**#####################***23**#####################***23**#####################***23 **#######################*****#######################*****#######################**** *#########################***#########################***#########################***... Injector open:^--------------------------^^--------------------------^^--- Cycle time:^---------------------------^---------------------------^--- 4 extra units of fuel. _____________________________________________________________________________________ 2***###################****12***###################****12***###################****12 ***#####################*******#####################*******#####################***** **#######################*****#######################*****#######################**** *#########################***#########################***#########################***... Injector open:^---------------------------^---------------------------^--- Cycle time:^---------------------------^---------------------------^--- 2 extra units of fuel. Edited by - Peter Carmichael on 11 Nov 2002 18:53:43 Link to comment Share on other sites More sharing options...
scooby dooby doo Posted November 11, 2002 Share Posted November 11, 2002 rob - I didn't mean to say that it was a universal colour code. sorry for the confusion if it read like that ❗ HOOPY 500 kg R706KGU Link to comment Share on other sites More sharing options...
V7 SLR Posted November 12, 2002 Share Posted November 12, 2002 Rob, I've checked with Caterhm and I do have the JPE pump. Apparently the SLRs, coming after the JPE all had them. In addition, I am most pleased with the big REDs, and agree that they will continue to offer sterling service with the 1227 cams. The only place where they might be slightly off is at idle where they appeared at the last mapping session to be slightly too big for decent emmissions. Perhaps the 1227 cams will change that..?? We'll work at it next mapping. I'm sure it isn't beyond DW's intellect to give me a lean map that I can punch in just prior to the MoT. BTW, we did swap the injectors over during the last mapping session, just to check for consistent fuelling. Although I didn't try all 4 injectors in branch 4 of the exhaust, the 2 or 3 we did try gave consistent readings. That said, if I can find someone local to give them an ultrasonic clean, I'll do just that. Hoopy, how did Rob tweek up the pressure on a non-adjustable FPR? Can you find out please? Worcs L7 club joint AO.//Membership No. 4379//Azure Blue SLR No. 0077//Se7ens List Tours Link to comment Share on other sites More sharing options...
scooby dooby doo Posted November 12, 2002 Share Posted November 12, 2002 V7 🤔 yerwhat ❗ 🤔 "Rob" 🤔 whose FPR 🤔 HOOPY 500 kg R706KGU Link to comment Share on other sites More sharing options...
V7 SLR Posted November 12, 2002 Share Posted November 12, 2002 Bugger, it wasn't Hoopy... it was Nick M. Nick, how did rob tweek up yeer fuel pressure? Have you got an adjustable FPR? Worcs L7 club joint AO.//Membership No. 4379//Azure Blue SLR No. 0077//Se7ens List Tours Link to comment Share on other sites More sharing options...
Nick M Posted November 12, 2002 Author Share Posted November 12, 2002 Yes, I have an adjustable fuel pressure regulator. It's one of these : http://216.242.145.16/products/product.phtml?p=10 As you can see, it will run from 30-70psi and it's a very well made piece of kit. Just wish I'd been able to pay US prices instead of UK ones for it !! Link to comment Share on other sites More sharing options...
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