I purchased a 2016 GT California Special last week. The car had 5k miles and I think I stole it for the price I paid. It came with a few mods that I wasn't able to get any information on during the purchase, but learned afterwards. It has a Livernois Motorsports Windstorm CAI. Today, I put the car on the lift to find out what was going on with the exhaust and found it has the American Racing Pure Thunder cat back exhaust, but without the H pipe. The H pipe was replaced with straight pipes.

My questions relate to the warranty. The dealer I bought the car from "guaranteed" me that the warranty is fully intact. Does this combination require a tune? If so, would a tune for these mods void the factory warranty? Lastly, anyone familiar with this combination know if there are any hp gains? My son says the car feels really strong compared to his 2014 GT. He has 3.31 gears and this car has 3.55, but the CAI and the exhaust might be making it even better. Thanks for your help.

 

The "windstorm" doesnt require a tune, nor does exhaust mods that dont mess with the cats. If it's the "severe windstorm" that does require a tune. I'm not quite sure on the removal of any crossover (H or X) pipe, but I suspect it might actually hurt performance by a few HP not having one. People usually say a x-pipe gives you 10 HP (vs stock)

 

Yes, the warranty is still good, but once you touch the tune you'll have problems getting warranty work done.

 

Just an update...I ended up returning this car to the selling dealer because I found it had body/paint work. I also tried removing the CAI to install in the new car I was going to get, but couldn't. I removed it, installed the factory air assembly, and took the car for a drive. It stalled 3x trying to pull out of the garage. At the end of the driveway, it stalled when putting it in gear. Tried accelerating and the car stumbled and seemed like it was in limp home mode. It drove REALLY bad. So, I went home and put the Livernois CAI back in. The car ran fine. That tells me the car has a tune and couldn't run with the airflow from the factory box. This was my concern when buying the car.

I told the dealer I was returning the car because of the paint and body work and the tune. By not knowing what tune the car had, was 87 octane hurting the car? Who knows? I bought a 2017 GT with 50 miles on it. I now know that this car is under full warranty and any changes done to it are done by me!

 

Smart move. Happy modding ahead!

 

what color is the 2017?

 

Magnetic

 

Problem solved.

 

That's the first time I've seen a true-dual exhaust on a V8 Mustang with no crossover of any kind (no X-pipe or H-pipe). It's used to equalize the exhaust pulses side-to-side.

I don't think switching to an X-pipe from the factory H-pipe gains any HP, unless the new crossover assembly has better-flowing pipes. What I mean by that is that my factory H-pipe had these 2 thin pipes coming from the cat-converter, with almost 90-degree bends in them, quite a restrictive set-up.
I had a local muffler shop cut out those sections of pipe and install 2.75" pipe, and even with their pipe bender not doing mandrel bends, it still flowed better due to the much larger pipe diameter.

I ended up replacing that H-pipe assembly with a 3"-to-2.75" JBA H-pipe, and it flows even better, mandrel-bent pipes and all.