Adeeb1395 Posted December 24, 2014 Share Posted December 24, 2014 (edited) If i boost an NA car how much fuel i need to add for every psi of boost?How much ignition timing retard needed? Edited December 24, 2014 by Adeeb1395 Quote Link to post Share on other sites
triple j Posted December 24, 2014 Share Posted December 24, 2014 Am not a pro tuner by far. But fuelling will be judged via wideband gauge and your timing will need to be pulled the use of det cans will need to be used. U can't just say how much will it need and punch that in because u will blow all for sure. There is other things to be done like uprated fuel pump,injectors ect before u boost. Quote Link to post Share on other sites
Stu Posted December 26, 2014 Share Posted December 26, 2014 As above, its not that simple. Depends on the ecu and its capabilities/resolution as well. What ecu are you using? Quote Link to post Share on other sites
TimD Posted December 26, 2014 Share Posted December 26, 2014 You will need 1 bar of fuel pressure per PSI. Quote Link to post Share on other sites
Adeeb1395 Posted December 26, 2014 Author Share Posted December 26, 2014 i am using AEM Fic6i hv heard i need to add 125% of fuel for every psi of boost for my ecu and retard 1 degree. is that ok? Quote Link to post Share on other sites
triple j Posted December 26, 2014 Share Posted December 26, 2014 Get a wideband and some det cans and maybe look a bit more in to tuning, 125% fuel per psi will most likely leave u bog rich with no power an injectors maxed depending on how much boost u are runnin, the timing isn't a bad place to start with the use of set cans that is, by the sounds of it u are just going to just punch in digits people is telling u. U will blow your engine this way that's a fact. Quote Link to post Share on other sites
Stu Posted December 27, 2014 Share Posted December 27, 2014 As above totally! Wild guesses will destroy your engine... I'd hope your software will show the 3D view of your fuel map and I'm assuming you have a tune that its running on and driving in vac load zones ie 100kpa and under.First thing I'd do it make sure the fuel map looks nice and progressive/smooth and isn't all erratic. The ignition table should be similar to a degree although there are reasons for dips and spikes. This will give you a starting point to tune from and its much easier than having a mine field of a map. Then just start tuning from there. Start low and build up - set your ideal target AFR then compare using the wideband to what you're getting - adjust zones accordingly. If its miles out then just adjust a whole row of cells across the table so you get the map roughed out before honing in and fine tuning. Idle/cruise is actually a bit trickier to tune I find but boost areas are fairly straight forward. There is no formula to work this out. Ignition is trickier and you can run quite a lot of timing in places but again start in small decreases smoothly adjusting the map as boost increases and keep and ear on the detset. Timing wise 4e's and 5e's take way more ignition timing than 4ages so you can be reasonably aggressive with the advance and not see det. But always use a good detset and pay attention to what your hearing - need to be pretty quick to back off if you hear any det. Here's what a smooth fuel map should look like: Quote Link to post Share on other sites
Stu Posted December 27, 2014 Share Posted December 27, 2014 Really?!!! Its advise like this you should not listen to. So to test your theory and assuming base factory fuel pressure is 43psi ish - then at say 10psi of boost you'll need 10bar more fuel pressure ie 145psi more? Most fuel pumps are not capable of going that high!!! Even a Bosch 044 is only capable of 5 bar. You will need 1 bar of fuel pressure per PSI. Quote Link to post Share on other sites
AdamB Posted December 27, 2014 Share Posted December 27, 2014 Go to a tuner who maps AEM. Don't listen to anyone on here, or anywhere else for that matter (no disrespect to those that actually do know what they are talking about), every engine is different and no one single person can give you an answer. There's a hell of a lot more to mapping than just pumping in some digits and getting a result, problem solving is key for mapping. Quote Link to post Share on other sites
teta Posted December 28, 2014 Share Posted December 28, 2014 Go to a tuner who maps AEM. Don't listen to anyone on here, or anywhere else for that matter (no disrespect to those that actually do know what they are talking about), every engine is different and no one single person can give you an answer. There's a hell of a lot more to mapping than just pumping in some digits and getting a result, problem solving is key for mapping. i know you said to leave it to the tuner dont take advice but like me where i live there are no one qualify to do it,some uses there experience since they been doing it longer thats all,we dont even have a dyno we have little or no option to learn on the net ourself Quote Link to post Share on other sites
AdamB Posted December 29, 2014 Share Posted December 29, 2014 i know you said to leave it to the tuner dont take advice but like me where i live there are no one qualify to do it,some uses there experience since they been doing it longer thats all,we dont even have a dyno we have little or no option to learn on the net ourself That's fair enough, but I would be looking at specific websites like efi101 etc that are specific to engine management systems and their programming rather than asking on a generic vehicle enthusiast website. Quote Link to post Share on other sites
Duduglanza Posted January 7, 2015 Share Posted January 7, 2015 To where you people bolt the detcans.. i made a set and cannot hear anything Quote Link to post Share on other sites
Stu Posted January 9, 2015 Share Posted January 9, 2015 Back of the block between the water pump and starter - on the cylinder wall is the best place. Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.