[roboha]

1. would under drive pulleys affect the air conditioner?
2. will a cat back exhaust system still pass md. emission test?
3. changing the fresh air system and power computer tune affect fuel economy?
4. if you have all four done what shoul one expect in hp and torque increase?
5, if all four mods. were done will the affect the factory warranty?
looking for straight answers to make my decision. i was told that i would have to switch
to 91 octane but woul increase fuel economy by 10% what do all think? thanks for any info roboha

[Crazy001]

hmmmm....good questions.


1. Some have had no problems, but I think underdrive pulleys are a bad idea. Your engine accessories are designed to run at a certain RPM range, and lowering that can cause problems. If you think about it, if it was such a great idea, Ford would have done it, and boasted more power out of the V6!

2. A cat back system does not affect the cat, it just replaces everything behind it, therefore it would leave all your emissions equipment the same. Shouldn't have a problem.

3. Tuning your engine for more power is going to use more gas! Where does the energy come from? Burning more gas! If driven conservatively, MPG shouldn't change much. But, in my experience, when people do these things, they push their cars harder, which trashes fuel economy. Some of the tunes will have you switch to 93 octane gas, which will get expensive after awhile.

4. If all four were done, i wouldn't expect much more than a few more horsepower out of the engine. It would make a difference, but I don't know if it would be worth the cost.

5. No, these mods will not affect warranty. HOWEVER....say your alternator or A/C compressor dies....Ford could claim that your underdrive pulley caused it, and then refuse to cover the repair. That's their right to do, as an underdrive pully will be running accessories out of their normal operating range. Other than that, nothing should affect the warranty.

On the last note, about 91 octane, and more fuel economy: Yeah right. Most tunes that use 91 octane advance spark timing, and will burn just as much fuel, and maybe more fuel if you like to accellerate a lot. Regular 87 is the most cost effective to run.

I hope this helps!

[kj_cinci]

1. Your new normal operating range will still be within Fords normal operating range, no extra wear if you ask me. The gear ratio is still close you just make it easier on the dirveshaft. Steeda even went to say this mod WILL NOT affect your warranty. But me too have wondered why Ford didn't do it...?? Anybody smarter? Is it from another car? Better A/C while idling?

2. Yes you'll be fine only problem might be noise abaitments in your area but a axle/cat back system with some mufflers should be fine everywhere. (If that's all you do to your exhaust don't waste money on a cat back, axlebacks will do as the OM cat to axle pipes are sufficient and very similar to AM pipes.)

3. Tunes alone always show on around 15 RWHP and a lower consumption!

4. I have seen dyno runs with exactly those mods and you should break 300 RWHPs. To me that's worth $1500...

5. Depends on your Ford dealer, what you need fixed (Shaker no, oil leak yes), and what parts/tune you have on the car bringing it in... But I'd say YES, it does void your warranty for the engine, maybe even drivetrain and brakes... Probably not since your shop (that will see it) get paid by Ford to fix it, but the answer is still YES as they can claim (and rightfully so) that the mods was the source for the damage, mailfunction, etc...

I will spring for the extra 2 bucks per fillup for a better running/performing engine and will tune it with the highest grade fuel... My belief is that it's better for the engine and environment in addition to the direct benefits such as mentioned and cold starts, ideling etc. etc...