Hey guys, I'm about to install a Berk 3" headerback exhaust (as soon as it ships), and was wondering if would be necessary to tune my AFR since the headerback may cause my car to run more lean. I know that in This thread, Takchi mentions that the CR S2000's come tuned rather lean from the factory, and that by removing the cat without a tune he would be risking detonation.

Now, I'm not sure if that would be a problem on my AP1 or not; I know that a tune would help me squeeze out a few more HP, but that's not really my primary concern right now, I just don't want to risk damaging the engine on a lean fuel mixture if it risks detonation. I would think however that the ECU would adjust itself though over time...

Anyway, let me know what you think guys. I'm hoping a re-tune isn't necessary at this point, as I really don't want to bother with tuning the car until I get something worth a dyno trip installed.

 

The MY01 S2000's actually ran rich from the factory, so it isn't 100% necessary, but I'd get it tuned at some point.

 

Cool deal. I hadn't actually thought about that, but my S2K definitely does run a little rich on cold and on the few occasions I've gone WOT my friend told me he could see some rich exhaust fumes.

Hopefully I'll get the car tuned by this time next year; If things go as I hope I may build enough cash for the King's Performance Stage1 Turbo kit and an AEM EMS Still talking about $7K all together though lol...

 

You are absolutely safe to run your ap1 like that without any tune.

 

Borrow or buy a wideband sensor and check the AFR yourself if you want to be 100% sure.

 

I have an AP1 as well w/ a heat tape wrapped OEM header, test pipe and currently an HKS. Been running this way for years. An AEM EMS is in my future along w/ a tune from Evans......but I feel safe for now.

Like you have I too have a Berk header back on order, BT1604-TP-AP1. Have they given you a ship date? Who was the distributor?

PM if you'd like.