I was told if you change the y-pipe, you change the amount of air flow and then the air/ fuel mixture is now "wrong" unless you now change the computer program to match the new mixture, or you have negative effects, like bad gas mileage. Any veterans who actually knooow if this is true. Give me some facts, not " my buddy said his car feels better"type of thing. thanks

 

Well, if you're going by what your buddy said, why can't we?

Modern cars have feedback mixture controls, via the computer, using the oxygen sensors.

 

Some cars are more finicky about tuning, but the 5th gen likes bolt-ons.

 

Most cars will keep the fuel ratio at the optimum level in closed loop.

Closed loop is like when your cruising or lightly accelerating.

When you floor it, the ECU enters open loop, and with certain mods, you may run a little rich or lean but it's really no biggie.

That's why alot of people get AFC's after they do significant mods.

(AFC= air fuel controller)

 

Been researching ECU flash and piggybacks (specific to a 5.5 gen with standard mods), and keep seeing a repeating opinion that the TS flash is more effective (for a 5.5 with standard mods). And then the AFC after the ECU flash, but with diminishing returns.

Unklejoe - is that about right by you?

 

I believe there is two different flashes from Technosquare. The one extends rev limiter and various other things and the other actually changes your fuel maps.

The only problem is that the one that changes your fuel maps is like $500, where as you can most likely find an AFC for like $200.

Also, the flash that technosquare would give you would be a generic flash and not fine tuned for your car.

Alot of people opt for the cheaper reflash that extends the rev limiter and then use a piggyback on top of that to correct the AFR.

I don't really know too much about this topic but I'm sure there are some people on here who can help you

 

good info guys, Soo there really is no negative effects to y-pipe and the other common things here unless you think more hp and gas mileage are negative effects! thanks

 

Yea I would say there is no negative side effects.

I'm not sure about the 5th gens, but on the 5.5, its actually better to get headers because you get rid of the precats that can sometimes deteriorate and get sucked back into the engine.

Not sure if the precats are on the manifold or on the y-pipe on the 5th gens.

On the 5.5 gens they are on the manifold.