does anyone know if the zex kit requires a reflash on an 05 4.0 auto? thanks

ORIGINAL: stang13

does anyone know if the zex kit requires a reflash on an 05 4.0 auto? thanks


techincally on a the 75HP shot, no you can run the stock Ford tune... however I highly recommend against it... on a automatic with the stock tune the shifting is way to soft... you'll want ot firm it up...

I would get a tune.

I know you had this setup scrimg but how hard was the install? Is there a button you push or does it just turn on at WOT? I think i might get this kit. Also if I stay with the 75 hp shot will my engine safely handle it. I know you lost a piston but I think you where pushing more to it. Also would you recommend a dyno tune if I did install the nitrous?

scrming blew a piston cause he got a little greedy and sprayed a 125 shot too low in the rpm range. (something like 2000 if I remember reading correctly)

The 75 shot tuned correctly is quite safe. I'd suggest a custom dyno tune with any nitrous system. There's too much that can go wrong that only a dyno with a wideband A/F meter can tell you.

Don't spray below 3000 (at least not until you're comfortable doing so). Only spray at WOT.

Ok but do you think the stock rear end would hold up. I plan on getting the t-loc with 373 gears but can only get one or the other.

ORIGINAL: chadlet

Ok but do you think the stock rear end would hold up. I plan on getting the t-loc with 373 gears but can only get one or the other.


My trac-lock and gear have held up to LOTS of 100HP shot runs and about 8 runs on the 125HP... this is using Drag Radials and an automatic... you should be fine unless your a manual tranny and your launching on slicks... and dropping the clutch at 5000 rpm!