I was thinking about getting underdrive pulleys. Are they really worth it? About what gains would I see and where would I go about purchasing them?
I wouldn't mess with the engine's balancing. Not a mod if you're
what do you think heads/cam does? changes the engines "balance"
That's not what was being asked. I, myself am uncomfortable changing the balance of an engine, especially at the lower most part...1onebadfox said:what do you think heads/cam does? changes the engines "balance"
Underdrive pullies do not change the engine's balance one bit.I wouldn't mess with the engine's balancing. Not a mod if you're going to keep the car for a long time, but that's my .02.
These engines aren't balanced with the crank pulley? It's not a harmonic balancer?Underdrive pullies do not change the engine's balance one bit.
Jasonhttp://www.miracerros.com/mustang/pulley_tech.htm said:Some Commonly Expressed Concerns about Underdrive Pulleys
1. Lowering the alternator speed will cause the battery to run down. That may be true for some people. If your driving style includes idling the car for long periods, or if you have a high end audio system that requires constant power from the alternator, underdrive pulleys may not be for you. The hot idle speed for a 2000 Mustang 3.8L V6 engine is 700-800 RPM. ASP claims that with its 25% underdrive set the alternator will provide a full charge when the engine is turning over at 850 RPM. I don't expect any problems in this area.
2. Lowering the water pump speed will cause the car to overheat in traffic. If your cooling system is in marginal condition, that could become a problem. An underdrive pulley will remove some of the margin of safety that Ford builds into its systems to account for clogged radiators, slipping belts, etc. If you keep your cooling system in good shape, it should not be a problem. I live in Southern Arizona where it gets HOT in the summer. I haven't had any overheating problems.
3. Lowering the power steering pump speed and the A/C compressor speed will result in decreased power steering and A/C efficiency. The people I've talked to who have installed 25% underdrive pulleys don't seem to notice any difference in A/C or power steering performance.
4. Installing a smaller crankshaft pulley can cause the crankshaft to fail. The people who say this always seem to be talking about the (stupid) practice of removing the harmonic damper and not replacing it when installing a smaller crank pulley. The damper is there for a reason, and removing it probably will result in damage to the crankshaft over time. Manufacturers of underdrive pulleys for the V6 Mustang agree. Their underdrive crank pulleys either piggyback on the stock pully/damper, or they come with a new harmonic damper to be installed along with the new pulley.
5. Underdrive crank pulleys are not compatible with superchargers. True. You don't want to underdrive a belt driven power adder. If you have any plans to install a supercharger at some later date, don't waste your money on underdrive pulleys now.
UPDATE August 2003: It's been ten months and 7,000 miles since I installed this pulley, I've had no problem with overheating, even when sitting in Tucson traffic in 110 degree weather. My battery has not run down. And I haven't noticed any difference in A/C or power steering performance.
UPDATE February 2006: More than three years and 40,000 miles with this pulley and still no problems.
Sigh...These engines aren't balanced with the crank pulley? It's not a harmonic balancer?
This was the issue with 6G72 engines (3000gt/stealth)... They were externally balanced and the crank pulley was the harmonic balancer.
For the OP:
Jason
+1 b1lk1...Sigh...
Anyhow, if you buy the correct kit for your Mustang it will come with the correct crank pulley. 94-98 are a pulley only change while 99-04 require a pulley/balancer (which is one piece) to be changed.
A proper kit that is made to proper specs will not change the balance of the engine one bit. I personally would not install one on my car as well, the gains are not worth it.
None.so i have a 98 mustang gt. how much off a difference would i notice while driving?