Muscle Mustangs & Fast FordsHow To Engine
Economical Turbo Kit - Wind Of Change
Building a 521hp, super-low-buck turbo kit for under $2,000!
Along with the tubing, we snatched up a couple of extra reducers (2.5 to 3.0 inch and 3.5 to 3.0 inch) to attach the turbo to the tubing and the tubing to the intercooler (in and out). CX also supplied an oil feed and return line kit, a couple of V-band clamps and even the T4 turbo flange needed to mount the turbo. Rather than go the homemade route for our turbo kit using the factory exhaust manifolds (or shorty headers), we snatched up a complete kit from CX Racing for just $199.
The availability of the turbo tubing from CX Racing means we can eliminate the do-it-yourself welding portion of the low-buck kit. For any single-turbo application, it's necessary to direct the exhaust gases from the factory exhaust manifolds (or shorty headers) to the turbo. The common practice is to flip over the stock manifolds or shorty headers and build a common Y-pipe to mount the T4 turbo flange.
If you take this route, don't forget provisions in the exhaust for a wastegate and oxygen sensor(s). CX Racing offered an affordable wastegate (less than $100), but we opted to run a new wastegate design from Turbo Smart. Its Hyper-Gate45 combined exceptional flow; a smaller, lightweight package; and revolutionary new locking collar to ease spring changes. It costs a little more (you can always go with the more affordably priced gate from CX Racing), but boost control is a critical element in a successful turbo application.
For the true low-buck approach, forget the tubular headers or mandrel-bent pipes--just get the exhaust to the turbo. It doesn't matter if you route the crosspipe under the pan or in front of the motor, just make sure to leave sufficient room for cooling as the exhaust side of a turbo motor gets pretty hot. The kit from CX Racing features 15?8-inch primaries and a 2.0-inch crossover tube.
To test the merits of our system, we went to a local wrecking yard and snatched up a bone stock 5.0L. If you have a 5.0L, your motor is essentially ready for low-buck boost. Nevertheless, we made a few minor changes to our "stock" motor prior to cranking it up. Knowing we're looking to more than double the factory output, we elected to replace the stock head bolts and head gaskets. We installed Fel Pro gaskets and ARP head studs. No changes were made to the stock heads, though it was difficult to resist the temptation to install a decent set of aluminum performance heads.
To properly illustrate the gains offered by the turbo kit, we first had to run the motor in normally aspirated trim. The 5.0L motor was run sans accessories, with a Meziere electric water pump and a set of stock exhaust manifolds. Naturally the MAF and attending air intake system were ditched on the engine dyno (the motor was tuned with a FAST XFI management system). In bone-stock trim, our high-mileage 5.0L produced a whopping 252 hp at 5,100 rpm and 306 lb-ft of torque at 3,600 rpm. Obviously tuned for torque, the 5.0L H.O. EFI motor offered 286 lb-ft all the way down at 2,500 rpm.
Prep for the turbo system included drilling a hole in the oil pan to serve as a drain for the turbo and upgrading the stock injectors to 36-pounders from FAST. The stock 19-lb/hr injectors were simply not going to get the job done. We installed the exhaust manifolds and crosspipe supplied by CX Racing. On went the 76mm turbo along with the oil feed and return lines (fittings supplied by CX Racing). Next, we positioned the intercooler and ran the supplied aluminum tubing from the turbo to the intercooler, then from the outlet of the intercooler to the throttle body. The position in the car would most likely be different, but the results would be the same. We then installed the supplied 3-inch downpipe section using the supplied V-band clamp to serve as the exhaust.