I bought my 2011 XJL SC a couple months ago and I absolutely love it. I was reading some threads about upgrading the tune to 575 hp, but... well, here's the thing: I really don't think it's on the stock 470 tune.

When I was driving it home the night I bought it a Charger Hellcat Redeye (with a YouTube channel sticker on the rear window) rolled up next to me on the highway wanting to race, and I decimated him. Twice. I was very surprised. So I'm thinking the previous owner had already tuned the car to at least 550, if not more.

Is there a quick way I can find out what tune it has, short of taking it to a dyno shop?

Thanks in advance.

 

I can tell if you have a tune using the SDD. Well more accurately I can tell how many times the ECU has been programmed.
BUT it won't tell me what brand it is.
I don't know how to identify the tune?

You could run a few 1/4 miles? Post the times and it will be easy to determine if your stock or not.
Might be the best way too?
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