Need a tune update for a muffler to straight pipe change?

Hello Guys,

So I am thinking of getting a new exhaust setup for motorsport events to both save some weight and create some noise. Will i need to modify my tune since it is just the muffler section being changed? I am always running on the high side of the Fuel Pressure diff offset, and usually running rich with the current tune.The idea is to take the muffler section off (pink) and create two straight pipes for each side (where the blue is). Not the best finger sketcher. Will take it off this weekend and see how loud it is, then hopefully get some new pipe fabricated up next week.

[img="https://uploads.tapatalk-cdn.com/20170720/ade654fd7730e533040f4ab2e2d03111.gifhttps://uploads.tapatalk-cdn.com/20170720/1bc03bef1d49d2ce7497972902564fa3.jpg" alt=""]

Any mod that changes the sound of the motor has potential to mess with the tune. You may need more fuel, you may need less, I simply can't tell you but it will change. Now the million dollar question is how much will it change and will you feel the difference?

Andy

Will depend on the Load source of your ecu, if the engine breathe better (or more) it will make more power if you add the right amount of fuel. If the ecu use MAF sensor to know how much Load is under, it may correct this perfect if the tune is "perfect", if it use MAP it will probably run leaner than what it was with the mufflers (more restrictions on the exhaust), if you run already in the rich size you will probably get away but you have to check that to run safe.

Felipe

Any modification that has the potential to affect the volumetric efficiency of the engine may impact the tune. How much effect this has will depend to a degree on how much the new muffler/exhaust affects the back pressure. My rule of thumb is to always check your tune when you make changes like this. better safe than sorry, plus you get to see the results of your mods.