Larger injectors, when is the need?
#52
Super Member
Since installing a 180mm crank pulley I have been experiencing some issues and thought it felt like a fuel delivery problem. When I purchased my E55 the injectors had only just been replaced and upgraded - or so I was led to believe - but upon checking the symptoms I am guessing that they were just replaced with original flow injectors. (It doesn't surprise me considering how dodgy the seller turned out to be....) I will have a look today to confirm and assuming I'm right will replace ASAP.
Most importantly though it appears as though the stock injectors cannot handle the 500 or so RWHP from my car and this seems to correlate with the figures below.
While researching injectors I came across this handy Fuel Injector Calculator which determines suggested injector size for a specified horsepower. Aside from indicating our cars need immediate injector upgrading it seems a little overprotective to me plus I'm assuming they are actually referring to RWHP rather than flywheel? Am I reading it wrong - can someone more knowledgeable set me straight?
The calculator can be found here: http://clean.injectorrx.com/fuel-injector-calculator/
I have included a couple of screenshots from the Fuel Injector Calculator; the first is for a stock E55 at 469HP the second is my vehicle with current mods:
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SCREENSHOT 1 @469HP (fuel-injector-calculator)
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SCREENSHOT 2 @630HP (fuel-injector-calculator)
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Most importantly though it appears as though the stock injectors cannot handle the 500 or so RWHP from my car and this seems to correlate with the figures below.
While researching injectors I came across this handy Fuel Injector Calculator which determines suggested injector size for a specified horsepower. Aside from indicating our cars need immediate injector upgrading it seems a little overprotective to me plus I'm assuming they are actually referring to RWHP rather than flywheel? Am I reading it wrong - can someone more knowledgeable set me straight?
The calculator can be found here: http://clean.injectorrx.com/fuel-injector-calculator/
I have included a couple of screenshots from the Fuel Injector Calculator; the first is for a stock E55 at 469HP the second is my vehicle with current mods:
_________________________________
SCREENSHOT 1 @469HP (fuel-injector-calculator)
_________________________________
_________________________________
SCREENSHOT 2 @630HP (fuel-injector-calculator)
_________________________________
Last edited by TheTherapist; 11-16-2014 at 11:42 AM.
#54
Super Member
Dashdaq is saying N/A for the AFR? Unsure why no reading there? The boost seems way down (not sure how accurate Dashdaq is there?) as it travels between -11 and -2. Timing also seemed really lean if I recall showing readings between -30 and -10 (roughly: those numbers could be out).
I did actually put some injector cleaner in and for what it's worth it appeared to make an immediate difference.
I did actually put some injector cleaner in and for what it's worth it appeared to make an immediate difference.
#55
MBWorld Fanatic!
You need the zt2 to read afr, it connects to the dashdaq, highest boost will be seen in 3rd gear on road test. You don't have the proper logging equipment to know if you are going lean
#56
Super Member
Yep that's what I figured.
She's running on around 50% power I reckon with sort of surges when accelerating and revving high. Drinking more fuel also.
She's running on around 50% power I reckon with sort of surges when accelerating and revving high. Drinking more fuel also.
#58
Super Member
#60
Super Member
Ya I did speak to Philip about 8 weeks back. I'm in Australia so planned on sending it with the cable. With the ec tune, the 84 sc pulley and other mods the car went like a rocket and when we dropped the 180 cp initially the pull was insane - felt like the car wanted to pull itself apart but power has gradually declined and circumstances have hampered repairs progress. So frustrating - especially with other issues that I attended to and was uncertain if they were related. It is only now that I have determined it is fuel related. And all along I have not had access to star das.
#62
Super Member
So if you reckon it's just the tune can I get away without upgrading the injectors yet or are they pretty much essential at this point also? Certainly that calculator to my reasoning says it is, although I know what the experts in this forum say also - what is your opinion on the calculator? It looks right and I have seen the same formula on a couple of sites, I just don't get why the injector capacities recommended should differ from what I read and know people to use?
#63
MBWorld Fanatic!
Yes the ecu will bleed off excess boost, there's a thread in here from sneakyneon from awhile back that his logs actually proved it, your car is running bad right now and I suggest getting a tune before you drive it hard again
#64
Super Member
sneakyneon did numerous 1/4 mile passes with a pulley with no tune and has logs to prove that the ecu was bleeding off the boost by opening the bypass valve
It's not recommended to do but it's unlikely you will blow up the motor as the stock ecu has fail safes and runs rich from factory
It's not recommended to do but it's unlikely you will blow up the motor as the stock ecu has fail safes and runs rich from factory
Sorry for sounding pedantic and worried but it is my baby we're talking about!
Last edited by TheTherapist; 11-16-2014 at 12:21 PM.
#65
Super Member
Oh and kponti sorry for hijacking the thread bro. Hopefully there's still plenty of relevant info since I've been posting.
#67
Super Member
#71
PLATINUM SPONSOR
to be safe, 500 to 510 RWHP and time to upgrade. Especially before the cold , high density air arrives.
__________________
E63 Biturbo, UPD Cold Air induction kit, UPD performance crank pulley and UPD adjustable rear suspension with ride height adjustment.
CL55 UPD Cold Air Boost kit, UPD 3000 stall converter, UPD 77mm SC clutched pulley and beltwrap kit, Custom long tubes, UPD crank pulley , UPD suspension kit, UPD SC pulley, Aux. HE, Trunk tank w/rule 2000 pump, Mezeire pump, UPD 5pc idler set, Aluminum rotor hats.
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instagram @ultimate_pd
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E63 Biturbo, UPD Cold Air induction kit, UPD performance crank pulley and UPD adjustable rear suspension with ride height adjustment.
CL55 UPD Cold Air Boost kit, UPD 3000 stall converter, UPD 77mm SC clutched pulley and beltwrap kit, Custom long tubes, UPD crank pulley , UPD suspension kit, UPD SC pulley, Aux. HE, Trunk tank w/rule 2000 pump, Mezeire pump, UPD 5pc idler set, Aluminum rotor hats.
www.ultimatepd.com
instagram @ultimate_pd
facebook.com/ultimatepd
#72
MBWorld Fanatic!
Thanks for the response, Brooke. I am already running 550cc injectors, have been for over 3 years now Would love to log IDC% with the dashdaq, but I don't believe there is a PID for it.
#73
and dont forget about the factory "blue" injectors that were phased in sometime around mid 2005 production. they have higher cc but i forget what it ended up being. there were a few arguments about it in other threads but they do actually have higher cc i think in the low 500's
#74
Super Member
anyone have the part number for the bosch 550cc? my injector guy can get them cheap, but want to make sure im ordering the right part number. thanks.,
#75
Super Member
550cc and looped rail is more than enough when you are approaching 500rwhp and above. 650cc is good to but once you go above 700cc, if they are not ID or equivalent high end squirtters, you will start to have drivability issues.
I was on 1000cc inj for e85, and drivability suffered.
I was on 1000cc inj for e85, and drivability suffered.