Weyro Posted June 12, 2012 Share Posted June 12, 2012 So im planning on taking my car to a garage to having the fueling checked, running a bar of boost and 3bar fuel on the rrfpr.I was thinking though, could i buy a wideband and do it myself? Quote Link to post Share on other sites
akyakapotter Posted June 12, 2012 Share Posted June 12, 2012 Yes you could and sat it up your self with a wide band Quote Link to post Share on other sites
Flaminsam Posted June 12, 2012 Share Posted June 12, 2012 Yea you can get it somewhere close to what it needs to be. Idle wants to be around 14.7 on boost wants to be about 13. Just to be safe. Funny onion has been doing loads of research on the matter and richer isn't really better. Quote Link to post Share on other sites
Jamie1st Posted June 12, 2012 Share Posted June 12, 2012 Yea you can get it somewhere close to what it needs to be. Idle wants to be around 14.7 on boost wants to be about 13. Just to be safe. Funny onion has been doing loads of research on the matter and richer isn't really better.an AFR reading of 13 seems abit high to me for on boost, just going from what cars a mapped to. I'd be looking in the 11's Quote Link to post Share on other sites
mattyD Posted June 12, 2012 Share Posted June 12, 2012 i think between 11.2-11.6 is good for when your on boost Quote Link to post Share on other sites
Flaminsam Posted June 12, 2012 Share Posted June 12, 2012 That's way too rich. Your going to give yourselves bore wash. Plus your sacrificing power. Perfect afr where everything is burnt is 14.7 parts air to 1 part fuel. This is also known as lambda 1. Too much fuel will rinse the bores of oil and wear the rings a lot quicker. Then when the fuel gets into your oil and sump it will reduce the protective properties of the oil and cause engine damage without regular servicing. Afr also gives you an idea of cylinder bore temp. If you have unburnt fuel the excess fuel removes heat from the bores. But this can also cause bore wash. Less unburnt fuel will raise bore temps to what they should be. I can go on for hours about fuelling. Quote Link to post Share on other sites
AdamB Posted June 12, 2012 Share Posted June 12, 2012 And running too lean you will burn out the exhaust valve seats, maybe even drop a valve head. Then you'll probably destroy piston rings, and manifolds, turbo's. Quote Link to post Share on other sites
Flaminsam Posted June 12, 2012 Share Posted June 12, 2012 Either way too lean (anything more than 14.7afr) and you run the risk of overheating the cylinders, burning valves out and melting electrodes on the spark Plugs. Not to mention blowing a rather large hole in the piston. At around 13 afr (the reason why I said if your going to be doing it yourself) you are not massively rich and you are on the right side of lambda 1. Anything more than 14.7 afr on boost and you run the risk of killing your motor. Quote Link to post Share on other sites
Weyro Posted June 12, 2012 Author Share Posted June 12, 2012 cool guys, thanks for the info.Im thinking i might go for a wideband now, is it just a case of adjusting the fpr higher or lower, till i get the right reading? Quote Link to post Share on other sites
rorenapier Posted June 12, 2012 Share Posted June 12, 2012 An AFR of 13 would be fine on a N/A motor, certainly not on a F/I motor.Standard or forged motor? Quote Link to post Share on other sites
Weyro Posted June 12, 2012 Author Share Posted June 12, 2012 its standard internals Quote Link to post Share on other sites
Flaminsam Posted June 12, 2012 Share Posted June 12, 2012 Wether its n/a or forced induction it doesn't matter. Afr is the same on both engines. Quote Link to post Share on other sites
Jamie1st Posted June 12, 2012 Share Posted June 12, 2012 (edited) Wether its n/a or forced induction it doesn't matter. Afr is the same on both engines.How many cars you mapped up dude?I know I wouldn't run 1.4bar through my engine if the AFR's were at 13, and I've never seen any forced induction cars mapped as lean as that either.I agree with the 14.7 when not in boost Edited June 12, 2012 by Jamie1st Quote Link to post Share on other sites
Flaminsam Posted June 12, 2012 Share Posted June 12, 2012 weyro is only using a bar of boost. hence why i say 13. 1.4 bar i would say be more like 12. i dont map cars. im a mechanic, and have been for 11 years. 1.4 bar is different. the inlet temps will be too high so you will need to put more fuel in to help cool down the cylinder temps. hence why when people start running over a bar they look into things like water injection or water meth injection to cool down the cylinder temps.also wether its n/a or turbo afr is afr. if you put 14.7 litres of air in the engine expect to put 1 litre of fuel in with it.either way its up to weyro what he wants to do, ive justified my reasons with an explanation. Quote Link to post Share on other sites
funny onion Posted June 12, 2012 Share Posted June 12, 2012 Agree with flaminsam. Richer isn't perfectly safe, it's not as risky as running lean but still. You're always compromising certain aspects when setting up Fueling in a way. Inlet temps on 1.4 bar will be a fair bit higher than for 1 bar hence the richer mixture to drop and maintain an even cylinder temperature. I'll out a pic up of my rolling road graph when my afr was around 11 on full boost, you will Lols Quote Link to post Share on other sites
Flaminsam Posted June 12, 2012 Share Posted June 12, 2012 cheers charl, was going to say can you put up your graph please also can you put up the one from race tech where it was lean but made more power. Quote Link to post Share on other sites
Jamie1st Posted June 12, 2012 Share Posted June 12, 2012 I haven't a clue then lol, yeah seen your pic on facebook I think.. I'm just going from what I seen on the froums and when Ive had cars mapped Quote Link to post Share on other sites
Flaminsam Posted June 12, 2012 Share Posted June 12, 2012 no worries jamie. fuelling is dependent on so many variables its unreal. but the general idea is if its rich its got unburnt fuel, this unburnt fuel acts like a heat soak and removes heat from the cylinder bores. easiest way to put it is like having a wet hand, when you blow on it, it feels colder. very similar principles to how air conditioning systems work. the reason it feels cold is because the water is removing heat from your skin trying to boil off or evaporate. same principle in an engine. The fuel is trying to evaporate so it will remove heat from the cylinders to boil off or evaporate. Quote Link to post Share on other sites
Jamie1st Posted June 12, 2012 Share Posted June 12, 2012 Yeah man, makes sense. I just thought AFR in boost was fairly constant, but after I think about it, the more boost, the more heat produced, so more fuel to keep it cooler. Quote Link to post Share on other sites
Flaminsam Posted June 12, 2012 Share Posted June 12, 2012 That's the badger Quote Link to post Share on other sites
AdamB Posted June 12, 2012 Share Posted June 12, 2012 (edited) Theres more to it than just having the "perfect" Stoichiometric lambda. An N/A engine will be totally different to a force induction engine, for starters it has a higher compression ratio, the higher the ratio the higher the octane rating needs to be to keep det away. Also an N/A engine is only able to draw air in at 14.7 psi or atmospheric pressure on the intake stroke. Even then if you take into account the resistance to flow before the air even gets into the cylinder your N/A engine will only be sucking in around 12 psi of air. This is around a 10% drop in peak power!Running an AFR of 13 on a turbo engine at WOT to me is ridiculous, your already increasing boost pressure, moving away from the turbochargers efficiency envelope heating the air at this point, plus the heat of resistance to flow. Without injecting a "safe" amount of fuel cylinder pressures are going to be high, and are more likely to induce det or even headgasket failure.Every engine will respond differently to X amount of fuel and Y amount of ignition, every batch of fuel you place in your fuel tank will be different. One engine may perform well at an AFR of 12 or another at 11.6.No offence but I know people that have been a mechanic for 25 years, a mechanic is totally different from a tuner, and for this reason I wouldn't let them build me a race spec engine. Edited June 12, 2012 by AdamB Quote Link to post Share on other sites
Flaminsam Posted June 12, 2012 Share Posted June 12, 2012 you know when you wish you had just kept your mouth shut? yup thats me now. good luck with the wideband weyro. Quote Link to post Share on other sites
daniel_g Posted June 12, 2012 Share Posted June 12, 2012 Nice swift exit haha, yeah mate let the pros do it. Normally i think people should have a play about with cars and do a few mods themselves but it really depends on the person. Also i'm a mechanic but i wouldn't really want to fuck about with AFRs. As said it is a job for a tuner, imo it seems a little bit sketchy trying to set up AFRs on a wideband by yourself, good luck man. Quote Link to post Share on other sites
Flaminsam Posted June 12, 2012 Share Posted June 12, 2012 i just hate the way when some one says mechanic that they just think of quick fit fitter. not trying to blow my own trumpet but when you play around with £2.5M of vehicle every day it kinda takes the piss. Quote Link to post Share on other sites
funny onion Posted June 12, 2012 Share Posted June 12, 2012 At the end of the day it's what the individual prefers. Mine runs like an absolute sack of shit when it's too rich. Unless you're boosting big you don't need it stupidly rich IMO. Id get a wideband and do it myself if i were you (IM in the process of doing mine). Can't wait to get it mapped as it is so much easier. Have a go and see what you think, Haters gonna hate . Quote Link to post Share on other sites
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