Why Do Some Cars Pop When Shifting Gears?
Originally Posted past: HIR07A
Originally Posted by: TwinMagician589
Originally Posted by: CW40
Mine backfires all the time and I don't have a supercar. The cars in the game (even the regular ones) are speeding and racing so we tin can presume they're running rich. I call up this causes backfiring. Information technology does in my machine anyhow.
That is really incorrect, real cars run rich on the idle and get leaner as the revs become up. The aim when tuning a fuel system is to choose the RPM range where the machine will be used the most - usually 3000 RPM for a regular car and make sure the transition from rich to lean happens at that place making the mixture STOICH at that given RPM for the sake of economy and power.
:)
Actually no, about EFI cars still run rich at wide-open-throttle due to them running in open-loop way (ie non relying on an exhaust oxygen/lambda sensor for feedback). At part throttle they will cruise in airtight-loop manner (trimming the fuel map based on the O2 sensor readings) to proceed AFRs near stoich for fuel economic system, just as shortly as you plant your foot the calculator disregards the O2 sensor (as it can't react fast enough) and goes off the internal fuel map. Stoich isn't where max power is made either (it is the ratio where combustion is most consummate), and running lean at loftier rpm tin be quite unsafe peculiarly for loftier-compression or turbocharged cars (misfires or detonation can grenade an engine extremely quickly), hence the extra fuel being dumped in as a precautionary measure.
Remember that when you lot bulldoze a motorcar in a game, chances are yous aren't driving it like yous do in real life (no-1 redlines their automobile in every gear and drives effectually at three-times the speed limit drifting everywhere), so you're not experiencing the aforementioned conditions. Most people will exist running in closed-loop stoich mode in existent life for 90% of their driving fourth dimension (except when idling), whereas in Forza you're commonly driving flat-out 24/seven unless you lot're cruising looking for bonus boards or merely enjoying the scenery.
I completely agree with you, I mentioned they become leaner as the rpm goes up, i did not mean they run lean. I was trying to avoid writing a book on it :)
In the example of a stock motorcar the manufacturer will always fix a condom compromise shut to stoich but nada leaner as they practice not know how it will be driven, and yes you are very correct on how it works 100% ( I always thought the new cars could get away with a fleck bacteria to improve ability and economy due to the knock sensor being able to find a ping before damage occurs and reduce the timing to a prophylactic betoken? i may be wrong - efi is non my potent point)
Lots of different tuning ideas apply to lots of different situations, HP vs economy, in some cases economic system does not play a role :)
I was talking nigh a racing situation where lean is desirable if you know exactly what is required from the motor and can make a safe melody for the state of affairs.
I cannot quote how the circuit guys prepare their mixtures or fuel mapping- not much experience there.
Im not a fan of EFI (im as well erstwhile) only I accept a long history of mechanical fuel injection in drag racing (methanol) and as well a lot of carby experience but the formula is the aforementioned. Lean =Power / Melted pistons. Its a fine line that you take to cut close for the win.
My bad habits are all drag racing based. The auto I was involved in had 54 fuel injectors - sixteen of which were only used to richen upwardly the mixture to get off the line without melting anything, afterwards that they were cut allowing a very lean mixture on the edge of destruction for the remaining laissez passer - we did supplant the pistons after every i/four mile along with every other engine component and a new 7 plate clutch. This car did consume 100litres of fuel in a 5 second pass and distorted the piston tops almost every fourth dimension. We ran a datalogger and every pass was diagnosed for exhaust temp, rail temp, humidity, air temp, traction, rpm, crank rotations etc etc and changes were made to the tune for each pass based on the terminal one. By the end of the dark we crept up on the leanest we could and thats why in drag racing the last run of the night is where records are cleaved. Besides the last run is a practise or die state of affairs then all the prophylactic tunes get out the window for the win.
Life in the fast lane huh?
(maybe now people volition understand why the in game drag racing is a thorn in my side the way it is)
Modern Edit: Sig size exceeds forum limits, 480x115 pixels max. Practise non repost. - D
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Why Do Some Cars Pop When Shifting Gears? UPDATED
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