Injectors ?
02-07-2009, 01:13 PM
#11
1.5 BAR
Thread Starter
Join Date: Feb 2007
Posts: 1,087
Re: Injectors ?
i could get a decent idle at like 13.2 but my part throttal like 20-15 hgin just is horrible either pig rich or really lean. people were telling me with a resistor box i get an un consistant voltage. im still newb at tuning my self but with my 450 i got the car to run how i wanted.
02-07-2009, 01:16 PM
#12
0.0 BAR
Join Date: Feb 2003
Posts: 0
Re: Injectors ?
People are silly. You get the same voltage consistency with or without a resistor box.
Sounds like you had some funky injectors. I see that a bit with the overbored stock injectors. It is not unusual to have to idle the bigger RCs at 13.5-13.8:1, but most everything else on the market should be tunable to the average intelligent person. If you got through one 450cc tune you should be able to do 1000cc with a small amount of extra effort.
Sounds like you had some funky injectors. I see that a bit with the overbored stock injectors. It is not unusual to have to idle the bigger RCs at 13.5-13.8:1, but most everything else on the market should be tunable to the average intelligent person. If you got through one 450cc tune you should be able to do 1000cc with a small amount of extra effort.
02-07-2009, 01:19 PM
#13
0.0 BAR
Join Date: Feb 2003
Posts: 0
Re: Injectors ?
Originally Posted by Joseph Davis
People are silly. You get the same voltage consistency with or without a resistor box.
Sounds like you had some funky injectors. I see that a bit with the overbored stock injectors, they do 440/450cc fine but the 660/680cc are a disaster. It is not unusual to have to idle the bigger RCs at 13.5-13.8:1, but most everything else on the market should be tunable to the average intelligent person. If you got through one 450cc tune you should be able to do 1000cc with a small amount of extra effort.
Sounds like you had some funky injectors. I see that a bit with the overbored stock injectors, they do 440/450cc fine but the 660/680cc are a disaster. It is not unusual to have to idle the bigger RCs at 13.5-13.8:1, but most everything else on the market should be tunable to the average intelligent person. If you got through one 450cc tune you should be able to do 1000cc with a small amount of extra effort.
02-07-2009, 01:21 PM
#14
1.5 BAR
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Join Date: Feb 2007
Posts: 1,087
Re: Injectors ?
thanks for the adivice i dont really wanna give up on them its a new year mabey ill try to stick with them since the cars down right now. i know i need to spend more time on battery offsets everyewere else the car ran great it was just idle and high vacume that was a PIA
02-07-2009, 10:37 PM
#15
0.0 BAR
Join Date: Aug 2005
Posts: 25
Re: Injectors ?
im new to tuning but i havent had much trouble tuning my precision 1000cc i did have to by a drive but now that i have that i can even get it lean at idle all im having trouble with is battery offset...well not really trouble havent even got around to messing with it yet but im sure when i get it set it will run great all im not sure about is there a way to control the voltage to be able to tune
02-08-2009, 02:53 AM
#16
1.5 BAR
Thread Starter
Join Date: Feb 2007
Posts: 1,087
Re: Injectors ?
they way i set my voltage was to hook up a battery booster and turn it on full voltage. ajust battery offset to on the highest voltage to run the same then unplug the alt and as voltage drops tune out your tables till it runs the same. im not having problem with the overall tune its just low vacume is inconsistant
02-08-2009, 03:16 AM
#17
0.0 BAR
Join Date: Feb 2003
Posts: 0
Re: Injectors ?
Voltage should drop when you turn on your headlights (high beams) and cut on your blower motor. Nothing is going to keep AFRs from fluctuating when the system is suddenly un/loaded, but pay attention to voltage and AFR with everything off vs voltage and AFR with everything on (after a couple seconds so everything stabilizes).
02-08-2009, 10:18 PM
#19
3.0 BAR
Join Date: Jul 2003
Posts: 6,449
Re: Injectors ?
The beauty of the Bosch 1000s (Injector Dynamics now) is that they are MATCHED SETS.
What does that mean exactly?
Say a company like Precision or RC buys 100 of the injector they are going to use to make there low imp 1000s. They flow them on a test bench using mineral spirits or some other calibrated test fluid at a fixed "max" duty cycle, say 85% duty cycle at 3 bar (43.5 psi). Out of those 100 injectors, they match them in sets of 4, 6 or 8 (depending on what motor) based on a flow number at one duty cycle. But does your car always run at this one static figure? No, of course not, injectors are "DYNAMIC"
The injector dynamics injectors are flow matched at a number of different pulsewidths and pressures. So the sets that are put together flow the same at 2ms, and the flow the same at 4 ms, 6ms, 8ms, 10ms...etc.
Injectors are most "finicky" at low pulsewidths and at very high pulsewidths. This is why there are varied opinions and reports about getting sets to idle correctly...some probably are closely enough matched to not see a difference where some sets can be off by probably around 10-15% between cylinders (at idle) and maybe at WOT.
What does that mean exactly?
Say a company like Precision or RC buys 100 of the injector they are going to use to make there low imp 1000s. They flow them on a test bench using mineral spirits or some other calibrated test fluid at a fixed "max" duty cycle, say 85% duty cycle at 3 bar (43.5 psi). Out of those 100 injectors, they match them in sets of 4, 6 or 8 (depending on what motor) based on a flow number at one duty cycle. But does your car always run at this one static figure? No, of course not, injectors are "DYNAMIC"
The injector dynamics injectors are flow matched at a number of different pulsewidths and pressures. So the sets that are put together flow the same at 2ms, and the flow the same at 4 ms, 6ms, 8ms, 10ms...etc.
Injectors are most "finicky" at low pulsewidths and at very high pulsewidths. This is why there are varied opinions and reports about getting sets to idle correctly...some probably are closely enough matched to not see a difference where some sets can be off by probably around 10-15% between cylinders (at idle) and maybe at WOT.
02-11-2009, 09:12 AM
#20
0.0 BAR
Join Date: Jan 2009
Posts: 1
Re: Injectors ?
I have dsm 450's and I was worried about the difficulty in tuning them as I have heard they can give you trouble , I am using neptune RTP and suprisingly I got them to behave pretty good idle 14.5 - 14.8 a toperating tempm warm up around 13.8 and they keep a steady AFR across the map , I didnt have to adjust the battery offsets I am just using the RTP's default offsets :| why is it that I didnt have to adjust them to get a nice idle?
