I would need a LOT more information about your build to give good recommendations. Have you got a build thread?
Yes. a standard crossflow has a very high G' moment of inertia as the piston changes direction. Poor balance, weak connection components and the type of fasteners don't help. The motor is plenty strong to spin at it's factory redline. But once you start exceeding 5krpm these forces fall outside the envelop it was designed for. Making 300HP at 7000RPM NA is going to be much more destructive to the engine than making 300HP at 4500rpm with 15lb boost.
From the best of my knowledge having matched headers on a turbo application, in order to have perfect exhaust gas pulse phasing, is far more trouble than its worth. The power/gain from doing so is not worth the effort/cost/drams associated with turned length headers. Up to you, But a home built, well designed log manifold made using steam pipe bends will be strong, less prone to fatigue failure and perform just fine.
A turbo similar size to a factory falcon turbo (GT35?) would likely be perfect, maby with a slightly smaller exhaust housing if you have the choice. But ideally before choosing your turbo you need to know your airflow and peak HP target. i am NOT a good advisory for turbo choice, you should talk to someone who knows turbos. Before you do, you need to know what your aim is.
Injectors. I can recommend the Bosch EV6 42lb injectors, Will bolt into factory fuel rail and injector manifold, even use the same electrical connector. TI performance sells them at a good price https://www.tiperformance.com.au/ it's where is got mine and i can confirm that they are genuine. But their flow capacity may not be big enough, depending on your HP Target.
I haven't put or finished my build thread yet, its in the pipeline. But I will give you the run down.
Enter engine has been re-built to factory specifications.
- Anti-Pump Lifters
- Roller Rockers
- Single with Damper Valve Springs
- New Valves
- Moly Chro Pushrods
- Gaskets and Other
- Bottom Block
The crankshaft and rods where shot peened and checked.
Enter motor was acid cleaned, honed and blueprinted. All professionally re-built.
Motor was balanced internally, all from:
- Pistons Balanced
- Rods Balanced
- Crank Balanced
- Bolts and End Weights Balanced
Motor Was also balanced externally:
- Harmonic Balancer
- Lightened and Balanced Flywheel
- Accessory Pulleys
The new head is a C2 head which has had head work done to it, with a valve grind done as well. It also has these weird lock type seals on the top over the valve guides (Might upload a pick)
The camshaft is Crow Cam with the following specs:
Is matched witth anti-pump lifters, moly pushrods (Nice and strong), 1.73 Adjustable Roller Rockers, and Single Spring with Damper, as well as new colletts and retainers.
The manifold will the original XF log manifold, with some port work done to it, I will be putting a larger intake throttle body on it, most likely from an LS with built in idle motor.
Got to run the relevant vacuum lines and what not
After Market Fuel Tank from the States, was mean't for a mustang, however made custom mounting plates, holds 85L, fully baffled with drop in fuel pump.
Custom 3/18 Full metal Fuel Line, with return line and filters.
Injectors will be Bosh EV14, 725CC at 70LB, will allow for alot of Head Room in HP
Then there will be the fuel regulator.
Current system is TFI Hall-Effect Dizzy matched with a MSD 6AL Programmable, with a huge MSD coil pack, makes a spark the size of a lighting ball.
The exhaust will be custom made, my welding isn't that good yet, and will be getting it to the best we can, still not sure if we want the turbo hanging or sitting on top.
Remote Oil Cooler for the Engine
Upgraded Three Row Radiator for Coolant
Slightly Beefed up Borg Warner 3spd Auto, with higher stall. It will be gone eventually, want to put a 5spd manual in it.
Frankenstein Diff, with a 9inch center, in a borg warner housing from the states. Has massive splines, and 9 inch flanges to suit.
Gearing is 3.45 LSD
Brembo Disc Brakes. 4 Pots with 320mm Discs
Probably something similar to the GT35, like the falcon turbo. I want something that will spool up early and won't run out of, and holds boost till 5000rpm.