History

In late March, we began the process of designing the Mustang GT turbo kit on a 2001 model 4.6 liter SOHC Bullitt edition Mustang. The timing of the process was a bit of a problem since seemingly everyone on earth was running behind on in stock parts. Backorders ranged from 2 to 7 weeks for some parts and ultimately we had to get parts such as the wastegate from sources outside of the United States. After a delay of 3+ weeks we were finally able to begin doing some serious work on the car.

For reference purposes, the car is a stock 4.6 liter SOHC with a 5 speed transmission. These cars average 234 HP at the tires in stock form. As stated above, this is a Bullitt edition car, and is #805.
 

The Guts

The guts of the prototype kit includes the following components.:

Turbonetics T04B turbocharger with .68 AR exhaust housing
Turbonetics Deltagate MKII wastegate
TurboX dual stage boost controller
TurboX type H blow off valve
Custom Spearco intercooler (1/2 PSI drop at 750 CFM)
Air/Fuel ratio gauge
Boost/Vacuum gauge
Pillar mounted gauge pod
Console mounted high/low boost switch
TransDapt oil filter relocation kit
Accel 34 lb/hr injectors
Walbro 255 LPH fuel pump
Blitz turbo timer
Performance Technologies turbo manifold
Performance Technologies intercooler hard pipes
Performance Technologies intake tubing
Performance Technologies stainless braided oil feed line
Performance Technologies oil drainback kit
Performance Technologies crossover exhaust pipe
Performance Technologies 2.5 inch downpipe
Performance Technologies Y pipe
Performance Technologies water inlet
Performance Technologies heat shielding

Results

The results to date are a bit predictable. Do to ongoing parts availability problems, the fuel pump had not arrived by the time we were ready to dyno and tune the car for the first time. For that reason the power output is less than stellar, although still quite impressive considering that both dyno runs were aborted at 4100 RPM due to fuel starvation.

The first dyno run netted 321 HP at the tires at 4100 RPM and 411 lb/ft of torque at 5 PSI of boost. The second run netted 306 HP at 3980 RPM. Both runs saw the air fuel ratio dip below 10:1 (the lowest the dynojet can read) until we ran out of fuel pump at around 4000 RPM. Each run saw an upward spike of 14:1 air fuel ratio and the run was aborted.

A customer supplied Diablo chip will be installed and mapped for a more suitable fuel and ignition curve for the next dyno run and now that the Walbro pump has arrived, the fuel supply should be more stable. The next dyno time is scheduled for  06/01/2002, at which time I fully expect to see 380 HP at 5 PSI of boost. The high side boost will be set at 8 PSI and should net well over 415 HP.

Keep in mind that this kit is still in the prototyping phase and changes in programming and/or some kit components are a matter of trial and error. The results will be posted here, good, bad, or ugly, as the testing continues.