Posted July 17, 200816 yr This has to be a chip issue, checked all other possibilities. Every time i put the boost up to 14psi i get det over about 5k rpm?? 12psi is fine? I ehink its got to be worth trying another chip. I currently have one from a forum trader but was thinking of a JD Chip??
July 17, 200816 yr Have you checked your fuel pressure ?. Did you run the dyno at Surrey ?. If so hav eyou got your graph, check the AFR lines. I was getting Det above 16 psi, but running lean even at idle. Fuel pressure should have been 45psi but was about 18psi.
July 18, 200816 yr Have you checked your fuel pressure ?. Did you run the dyno at Surrey ?. If so hav eyou got your graph, check the AFR lines. I was getting Det above 16 psi, but running lean even at idle. Fuel pressure should have been 45psi but was about 18psi. IIRC running lean at idle isn't that bad - but it will raise your HC figure when MOT man does the emissions check.
July 19, 200816 yr Well considering that the ideal AFR line should stay on 12 all through the range. This is what I consider a little too lean ;)
July 30, 200816 yr Double check the timing, make sure it's properly warmed up when checking and that temp sensor is working correctly. If you use the inductive loop for checking timing try the alternative method with a length of HT cable and plug cap between direct fire coil (incorrectly referred to as a 'coil pack' ;-) ) and plug terminal. Both methods have been reported as giving 'odd' results so trying both should rule out any inaccuracy... Has your det sensor been bypassed? Have you checked all injectors and CAS are working reliably? Fuel pressure also looks like a good bet...filter replaced? What plugs are you using? You should be on a colder grade and pref with smaller preset gap (= shorter ground electrode) if making over 400BHP, 2 grades colder if making 500BHP+, downside being idle may not be as smooth and fouling may occur in town traffic. Cheers H
July 30, 200816 yr In the same way as SMW1 above, is that incorrect? Air Fuel ratio is not fuel pressure although they are related, why don't you post up your dyno sheet?
July 30, 200816 yr The timing is retarded to 14 degrees Hiya James forgive me if i'm wrong cos i aint read the whole thread :smash: but is'nt your timing supposed to be 15 deg?
July 30, 200816 yr Hiya James forgive me if i'm wrong cos i aint read the whole thread :smash: but is'nt your timing supposed to be 15 deg? it is but retarding it 1 degree would help it run slightly safer i would of thought?
July 31, 200816 yr it is but retarding it 1 degree would help it run slightly safer i would of thought? Should definately reduce the chance of det :) CheerZ, Vern
August 13, 200816 yr Finally scanned my dyno results. Mark, does this look ok??? air flow on about 14.5 looks about right to me!!! anyone else?
August 13, 200816 yr your looking at the wrong line mate, your looking at HP, Looking at my dyno sheet, your about right. I think im right in saying the AFR should be around the 11.5 area on full boost. Edited August 13, 200816 yr by nickz32 i was being a clot
August 13, 200816 yr Look like its leaning out halfway up the rev range, but peaks again after 6000rpm. Your boost is nice and consistance across the rev range, but for some reason your not getting the fuelling, especially at about 4800 rpm You're looking at the line upside down. 4800 is it's richest point.
August 13, 200816 yr You're looking at the line upside down. 4800 is it's richest point. Ive just notice that as i was looking at my dyno sheet. What a clot!
August 13, 200816 yr your looking at the wrong line mate, your looking at HP, Looking at my dyno sheet, your about right. I think im right in saying the AFR should be around the 11.5 area on full boost. god i give up when looking at graphs :( all i remmember is sw1's on about 12 which was lean.
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