Will I need a bigger intercooler with a bigger turbo? This is a very hard question with many opinions and not a great deal of facts. There are quite a few aftermarket turbo users posting impressive numbers with even the stock TMIC. This isn’t to say that they wouldn’t benefit from a larger intercooler, but it shows that it may be considered a supporting mod worth serious discussion and consideration during or just after a turbo upgrade. This decision should be discussed with a trusted Vendor or tuner for the best advice as to what suits your needs.
Subaru WRX/STI turbo charger basics
How hard is it to install an aftermarket turbo? Allow around one hour for install time. Professional installation, depending on your area, is around $75. This is one vehicle modification that is very simple and can be successfully accomplished by even the greenest shade tree mechanic. Rotated mount installations are much more difficult and may require professional assitance due to needing custom exhaust work, TGV deletes, etc.
Do I need engine management/tuning with a new turbo? Yes. The only bolt on turbo that will require no tuning/engine management is a ported and polished stock turbo. All other turbos will require tuning and supporting mods.
Is there any additional advice for turbo installation?
Materials Checklist:
Downpipe Gasket (DP to turbo) ~$20
Uppipe Gasket (uppipe to turbo) ~$11
1 qt of oil
1 qt or so of coolant
Prior to/during turbo installation:
1.) Pre-oil turbo
2.) Prior to removal of any bolts, spray with a oil penetrate such as PB Blaster and allow to soak for 5-15 minutes.
3.) Uppipe to turbo and turbo to downpipe bolt torque spec is 26-30 ft. lbs.
After turbo installation:
Crank engine for 20 seconds to lubricate turbo (by pulling the ‘IGN’ fuse)
Let idle for about 30 minutes
Check for leaks and fluid levels several times
Break turbo in for a couple hundred miles (for new turbos)
Change oil after break-in (for new turbos)