Lifetime Supporting Member
Join Date: Dec 2011
Location: Tallahassee FL
Bullitt Year: 08
Bullitt Color: HG
Bullitt Serialized Number: 4370
Once you modify the air intake sizes beyond OEM specs, a tune is necessary. That includes the CAI tube, throttle body and intake manifold. The computer is set for the OEM specs.
The Bullitt throttle body is the GT stock 55mm. The next step is 62mm. A tune is required.
A tune is set for a specific octane rating, so the unique Bullitt "octane sensor" (Knock adapability) is disabled. Good canned tunes are hard to find.
Just adding the FRPP 62mm throttle body ($600 and very pretty) is the start. To gain the full effect, the FRPP intake manifold ($600), FRPP hot rod cams ($750) and short or long tube headers must be added to gain the full effect of increased HP and torque at high RPM. Even so, torque and HP gain at low RPM is minimal.
Some aftermarket TB's reuse the motor from your OEM TB, which is why they are cheaper. But binding issues can then happen.
I have the Steeda underdrive pulley, good, cheap performance mod. No tune needed. No issue with A/C cooling and power steering.
MY motor is stock. run 87 octane for road trips and am happy, saving $. I do run a 93 tune for the road course track, mainly as the tune eliminates throttle lag at apex.
Yes, the BBK short tube headers will increase some HP and give some louder noise at a reasonable price. No tune needed.
Mufflers are a totally different issue, but with no tune needed.
For performance, look at a 1piece aluminum drive shaft is great. No tune needed. Over half the the rotational mass.You will definitely feel this on acceleration and no more drive shaft banging. You will then want a new shifter (MGW).
Hopes this helps. Look for no tune needed. Ford did a good job with the OEM computer. Just beware the law of unintended consequences of vehicle modification.
Last edited by tossass4370; 10-08-2019 at 03:03 AM.