3.5” exhaust

What tuner do you guys recommend. And idk how to figure out the afr issue. Iv boost tested from the air filter back and there is no leak the issue was there before aux fuel. Also took it to a mechanic and they couldn’t figure it out.

 

Make a thread about it and tag me in it. I have a sneaking suspicion I already know what it is, as it's been an issue trending with other people I've helped recently.

 

Freektune - Justin or PurpleDrank - Will are the best tuners for the platform.

you 100% need to figure out the AFR issue before proceeding with tuning. A good tuner would have stopped after the first revision to make you get it sorted.

 

This this this this.

You wouldn't trust a Dr that had no problem operating on you if there was a moderate to high chance it would result in your death and he/she was like "fuck it, yolo lol!" That's basically what you have here. Looking at your AFR curve, you are one WOT pull with bad conditions away from needing to install a screen door in your block.

 

https://mazdaspeeds.org/index.php?threads/lean-afr-during-wot.15272/

 

Just an FYI: CST5 runs out of steam at 31-32psi with a peak rpm of 7500rpm. This makes 530whp with some taper down above 6500-7000rpm depending on headwork. I've seen this power curve repeat itself a few times on well sorted MS3s on a dynojet or other dyno with same dynojet equivalent calibration. You can make more torque (I've seen 550ftlbs) at lower rpm as the turbo can light off pretty quick if desired.