Yes I know this isn't a chip question,but I'm sure Mike or whoever reading can get me a quick answer...I have Steeda underdrives(3 piece set)..I'm only useing the water pump and crank pullies Using stock Alt. pulley...Will this set up still slow down my Alt? I'm having voltage issues with my truck...I have a SERIOUS stereo load now(new set up)...I've done everything to counter act voltage problems that I can think of...
-Optima yellow top..
-220 amp alt.
-1/0 power wire
-5 farad cap
-increased enginge ground size to #4
-added a parallel#4 from batt. to alt.

What do you think?

 

Hi RF-1,

Those are Mustang pulleys - they aren't designed specifically for these street-driven F-150's, and many people have tried to save a few bucks using March, Steeda, etc. pulleys, and have found this out the hard way - sure, they'll fit, but they are *not* engineered for street-driven trucks.

It also doesn't matter that you aren't using the alternator pulley from that kit (well, unless that alternator pulley is designed to actually speed the alternator back up), in these F-150's that one serpentine belt drives *everything* in the entire accessory drive chain (Lightnings & supercharged Harleys excepted) - so just the crank pulley by itself certainly *is* slowing down your alternator and everything else in the entire accessory drive chain - by a bunch.

This is exactly why we do not use March, Steeda, or any other pulleys that are actually designed for the 4.6 Mustangs - not because they aren't good quality, sure they are generally good quality, that's not the issue - they are just far too aggressive for these trucks. In fact, we use our truck pulleys on a lot of 4.6 Mustangs precisely because most of the Mustang pulleys are too aggressive for the street even for Mustangs - they're great for a drag-race only Mustang, but not for the street where you may have to idle at night sitting at a stoplight with the A/C, headlights, stereo, etc. all on - even with a manual transmission.

A/C performance, alternator performance, power steering performance, etc. are critical in these heavier trucks. You'll actually see reference to the Mustang 4.6 in our F-150 underdrive pulley instructions, because we use them on the 4.6 Mustangs if they are driven on the street.

Our 2-piece set for the 1997-2004 V8 F-150's (all years from 1997 on up, including 2004, and with 4.6 or either 2-valve or 3-valve 5.4's) only requires 850 rpm of engine speed to provide normal alternator output. We use a smaller crankshaft pulley to slow the chain down, and then a *larger* water pump pulley to restore proper coolant flow thru the motor.

There is an option that a number of people have had us do for them in this situation (where you have already upgraded to a bigger alternator, but still don't have enough power at idle), and that is to have us do a custom tune for your truck - for the automatic transmission models, we can just bump up the idle speed in gear - we can move it up in the program just enough so you've got sufficient alternator output, power steering output & A/C performance in summertime, when idling in gear.

For those with manual trannys, they obviously don't have an "in gear" idle speed adjustment, they just have the basic idle speed parameter - so we just bump that up a bit and that takes care of allowing them to run the pulleys they want along with a lot of other things like electric fans & underdrive pulleys, big stereos, a lot of auxiliary lighting, etc. - even all of that combined. Some of these trucks will also have power steering idle "switches" as well as A/C idle speed adders - and if the truck has that, then we also have control over that, too - like if someone has 37" tires & has to parallel park frequently, we can just increase the amount of idle speed added *only* when the pressure in the power steering pump hits a certain level, or only when the A/C compressor clutch is engaged, etc.

Those big rewound (or the high $$ custom-made) 220 amp alternators don't make 220 amps of actual output unless the engine is turning significant rpms, usually above 2500 rpm or so - at a typical idle speed of about 600-650 rpm, they aren't delivering a whole lot more than stock amperage. Once the engine can spin some more rpms, *then* they can put out a tremendous amount of additional output over stock.

It's nice that you've upgraded the battery to an Optima, a 220 amp alternator, bigger gauge ground & power cables for the battery, etc. those are all great ideas and needed with a really big stereo setup - but they won't fix your problem of having a set of Mustang pulleys that is far too aggressive for any street-driven F-series.

Assuming proper installation of that stereo setup and no other problems with the vehicle's charging system, you have some options..........................

1.) Go back to your stock pulleys.

2.) Have us do a custom tune that bumps up your idle speed (as well as gets you even more power gain than your present Superchips tune) a bit, so you'll have the power you need at idle.

3.) Have us do the custom tune and switch over to our underdrive pulleys. (really shameless sales plug)

Give us a call to go over this in more detail - we'll be happy to help, as always.

 

Another amazing answer Mike ..Thank you..I was planning on going back to stock..I just wanted your input..I don't see the need right now for another underdrive set up..I will keep you in mind as always..A few ponies aren't going to help with the weight of my system,and some heavy 20" rims...

Thank you again!!!

 

Hi RF-1,

I hear you - it's a shame you can't use those pulleys, as they certainly do free up some power, and help throttle response down low - but if you don't have enough amps, then you don't have enough amps.

Just a thought here - you could just go back to the stock pulleys for now, and then if your budget can tolerate it at some point in the future, have us do the custom tune to bump up that idle speed as needed (and get even further power gains) so you can put those pulleys back on and get that additional power gain, too. Some of the power gain from underdrive pulleys is available right there from just off-idle which helps off the line & low-end response - they're on of my favorite mods, as I like anything that reduces parasitic losses.

Have fun & good luck!

 

Just a note. A larger water pump pulley will slow the pump, not speed it up. With the exception of the drive (crank) pulley, anything else will be slowed by using a smaller pulley.


Roushfan-1,

If your alternator pulley is smaller on the aftermarket set, use it. Most that I have seen are made this way. I have FRPP pullies on my 5.0 truck and the alternator pulley is smaller, in an effort to bring charge closer to stock rpm requirements.

 

So if i buy a 3 piece set (i am currently looking at bbk and mac) and get a custom superchip, the idle can be bumped up to help with the alt charging? i dont have any extra load on my elec system (no extra lights, no big stereo, etc) and i dont plan to, so should this set up be ok on my truck? i do mostly highway driving (about 60-75 miles a day) and very little city driving.

thanks.

 

 

Yo Spaceman!

I'm right up ol' 55 from you!

I think Mike might be on vacation or something. I e-mailed him a question Friday and haven't heard from him. His rep would indicate that's not normal operating procedure!