KeithTheBricklayer Donating Members 450 Member For: 15y 1m 10d Gender: Male Location: perth Posted 15/06/10 08:40 AM Share Posted 15/06/10 08:40 AM im not I know oncei get stuff done ill keep going.. why I ty get better gear so no need to upgrade on that al cruise dean u were sayin they making 10inch dark argent fakies? so whats the go Link to comment Share on other sites More sharing options...
IH8TOADS Silver Donating Members 3,618 Member For: 19y 5m 24d Gender: Male Location: OZ Posted 15/06/10 08:44 AM Share Posted 15/06/10 08:44 AM Yeah I know what you mean but I'm just an@l lol. Deka's are still fine for lower power, no probs there either. You need to be shown in practice to appreciate where I'm coming from. Even common nizpro scaling is engineeringly flawed, an injector low slope should not be lower than the high slope. Link to comment Share on other sites More sharing options...
Buf-Phoon loitering with intent Lifetime Members 13,318 Member For: 21y 4m 13d Gender: Male Location: Zombie Birdhouse Posted 15/06/10 09:06 AM Share Posted 15/06/10 09:06 AM Toad, to an extent I agree with Slash. I have had 370 rwkw at the treads for some time with Dekas, no cold start problems, perfect idle , crisp power delivery and great fuel economy.Or is my car a low power application ?In your opinion are many shops tuning these squirters properly, as there have been hundreds of cars succesfully tuned with these across the country.What are the downside/positives with running these, and what should we look for in our tunes, given we generally only get power, boost, torque and AFR graphs ?Not being a smart arse as you have obviously spent a lot of you own time understanding this popular brand of injector.Curious tis all Link to comment Share on other sites More sharing options...
RIP_HSV HOON Member 1,636 Member For: 14y 9m 17d Gender: Male Location: W.A Posted 15/06/10 09:14 AM Share Posted 15/06/10 09:14 AM It's worth considering I have 42lb injectors lined up to go in too. Low 300's is my plan so a full exhaust is probably going to be overkill? Decisions decisions... Ahhh...Bosch injectors are nasty, I agree with Dean you should go for a set of deka's Link to comment Share on other sites More sharing options...
IH8TOADS Silver Donating Members 3,618 Member For: 19y 5m 24d Gender: Male Location: OZ Posted 15/06/10 10:21 AM Share Posted 15/06/10 10:21 AM Toad, to an extent I agree with Slash. I have had 370 rwkw at the treads for some time with Dekas, no cold start problems, perfect idle , crisp power delivery and great fuel economy.Or is my car a low power application ?In your opinion are many shops tuning these squirters properly, as there have been hundreds of cars succesfully tuned with these across the country.What are the downside/positives with running these, and what should we look for in our tunes, given we generally only get power, boost, torque and AFR graphs ?Not being a smart arse as you have obviously spent a lot of you own time understanding this popular brand of injector.Curious tis allWithout logging you would never know anything was wrong....and in the end of the day it kinda isn't because nothing gets damaged which is why I do agree with the comments you and slash have made :-) But I'm fussy. I'll try and explain things a little better. The injector ‘slopes’ refer to the actual fuel flow vs pulsewidth. Tuning is all maths and in ‘maths language’ the slope is defined as rise over run. When you plot injector flow on the Y axis and pulsewidth on the x axis you will see that the ‘slope’ is steeper at low pulsewidths. I.e. the injector flows more fuel for a given pulsewidth. As you increase the pulsewidth the flow hits a ‘breakpoint’ and from here on the slope becomes more linear and less steep (more run and less rise!). So for the PCM to be able to fuel the car correctly it needs to know the low flow characteristics of the injector, the high flow characteristics of the injector and the breakpoint at which it switches between slopes (flow rates). Basically the pcm is trying to model the flow characteristics of the injector as the flow rate is only linear down to a certain pulsewidth. In the case of nizpro scaling, if you edit the PCM so that the low slope has a lower figure than the high slope (common scaling) so that your closed loop correction is buggerall at low pulsewidths (I.e. the long term fuel trim is around 1.0), then the PCM is going to inject more fuel when really it should be injecting less! In this case a tuner would have left the battery offset table as factory and the deadtime adder is not large enough (the offset and low slope work together at low pulsewidths). As such the tuner has had to richen the low slope so much it is now below that of the high slope. This will get the injector working in the software, however it is engineeringly wrong as the mechanics of the injector stipulate that the steepness of the flow curve/line is greater at low pulsewidths yet the software has been told the steepness is less! Ever heard anyone complain about nizpro cold starts in the past? Moving on to the deka’s. Leave the battery offset values as factory and again the PCM is going to be fighting against the mechanics of the injector. Tuners who leave the offset at the factory calibration end up having to lean the low slope off massively as the deadtime adder/offset is way too high! All round you would never know or feel a difference in your cars performance, but again $hit just ain’t engineeringly correct and your PCM is not correctly modelling the mechanics and ACTUAL slopes of the injector correctly…..remember back to our maths and the rise over run. So on a cold start when the PCM is in open loop fuelling for a bit, your AFR’s are going to be pig rich as the deadtime adder/offset is simply adding way too much fuel. Once it switches to closed loop you’re long term fuel trim is going to be removing 12 – 20% fuel constantly (we’re lucky the O2 feedback correction works so well to bring fuelling to stoich). Your cold starts are so good with the deka’s a lot of the time because these engines idle nice on a really rich start! The closed loop system works really well in the fords which is why tuners can get away with incorrect scaling. So now I will post a question to see if anyone has learnt anything lol. Question is based on real data. If you log an 800rpm idle pulsewidth of a deka 60 (~70lb/hr flow rate @ 4bar), nizpro 72 (~71lb/hr @ 4bar) and a ID1000 (~110 lb/hr @ 4bar) in a warm XR6T operating in closed loop (14.64 AFR) you will see ~1.62ms, ~2.0ms, and ~1.85ms respectively. Tell me why these have different pulsewidths in this car operating under the same conditions? Link to comment Share on other sites More sharing options...
RIP_HSV HOON Member 1,636 Member For: 14y 9m 17d Gender: Male Location: W.A Posted 15/06/10 10:27 AM Share Posted 15/06/10 10:27 AM holy sh*t man, ive got a headacheso Deka's or Bosch in your expert opinion? Link to comment Share on other sites More sharing options...
xr6t ego Member 1,112 Member For: 18y 8d Gender: Male Location: PERTH WA Posted 15/06/10 11:00 AM Share Posted 15/06/10 11:00 AM Pass Link to comment Share on other sites More sharing options...
IH8TOADS Silver Donating Members 3,618 Member For: 19y 5m 24d Gender: Male Location: OZ Posted 15/06/10 11:09 AM Share Posted 15/06/10 11:09 AM always best going with your tuners advice IMO rip hsv, cost is also important which makes the dekas an attractive choice :-) Link to comment Share on other sites More sharing options...
KeithTheBricklayer Donating Members 450 Member For: 15y 1m 10d Gender: Male Location: perth Posted 15/06/10 11:21 AM Share Posted 15/06/10 11:21 AM yeh I cant complain I got 340 intake pump *genuine band new not used* an second hand dekas for 400 bucks cant complain an was running in a car tunned by xft running 350rwkw's Link to comment Share on other sites More sharing options...
RIP_HSV HOON Member 1,636 Member For: 14y 9m 17d Gender: Male Location: W.A Posted 15/06/10 11:27 AM Share Posted 15/06/10 11:27 AM yeah I agree, use what your tuner likes to use, theres a set of Deka's in for sale section for $250 Link to comment Share on other sites More sharing options...
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