[WilltheThrill]

one of my friends recently got a 04 termi. he told me that hes getting a 2.8 pulley. how important is it that he takes the car to a shop and gets it tuned after the swap(to prevent detonation)???

[1Badsnake]

When you start changing pulleys, tuning is necessary!
1. It changes the max revolutions of the SC (intervals for SC oil changes goes from 100k down to every 30K-60K depending on other variable.)
2. Can change the boost (Ford states max boost for Eaton is 8LBS)
My pulley set-up was 2.8lb upper w/ 10lb lower (ran 21lb of boost before I was informed by Brent @ Dynotuned Performance that this was unsafe. So he advised keeping the stock 3" and the boost went to a more safe 15lb. Not sure if I believe Ford's 8lbs max because the compound boost set-up of twin 66mm going to a stock eaton sent 42lbs into the intake (Modified Mustangs Magazine article).
3. 2.8's even with appropriate belt size and tensioning can belt slip BAD! I went through
2 belts in a year!
4. Are difficult to change even with the appropriate removal tool ( SC and car have got to be completely cool)

[Doc8224]

Its not that you need to take it to a dyno shop, most companies sell a tuner/pulley/puller combo that will be all he needs. definatly need a tensioner for the 2.8. Ford says max 8psi to cover their but and most of the time if you read it it says the stock "setup" is max 8psi. Not the eaton is max. The eaton is good beyond 8 that is for sure. As for the compound boost and what the eaton can produce, the eaton isn't having to make all that boost so its not have to work harder, therefore you aren't hurting it any at all. But the compound setup and the stock setup is comparing apples to oranges. I would tell him to get a pulley tune from any of the reputable sct or diablo shops or get a dyno tune if he wants the max gain out of it. Definitly don't run it without the tune.

[1Badsnake]

The internal have been tested to 20lbs, but Ford recommends not going over 16lbs w/o detonation. The info on compounding is strictly that info. Please don't read too far into it!