Installed the underdrive pulleys

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Back in February, I bought a set of Steeda underdrive pulleys for my Grand Marquis. Silly me, I opted to have them shipped directly to Kuwait through USPS, instead of having them shipped to DHL's forwarding service in OH. It arrived in Kuwait 8 days after it was shipped, but got delivered the other day. Local post is terrible. Temper aside, I installed them yesterday (just the crank and water pump, left out the alternator pulley as I have a sound system installed). First impressions:

Idle
Wow - you barely feel the engine running. A definite improvement.

Steering
The steering feels a bit heavier, and overall I like the feel compared to how light it was before. Another bonus.

Get up and go
With a conventional 3.08 rear end, I always had a one wheel peel from halt at half throttle, and had to be feather light on the gas. Not a good thing when you need to go. Not sure what the connection is, but the pulleys seem to have stopped that. Another plus point.

Only downside is, it seems to have lost a bit of low end torque from a complete halt and I reckon that's what stopped the wheelspin. When when you're on the highway, or in a situation where you need to accelerate quick, there's no longer any need to go WOT. Acceleration is very strong in third now, and even better in second. Lacks a bit of guts in first, but that more than made up for it.

Cooling
I have a 180 F thermostat installed. Head temps mostly hovered in the 188-190 F range based on my ScanGauge. The AC commands the fan to come on, so with the AC off, head temperatures got up to 194 at idle. Turn the AC on and it drops.

Getting the tune redone for the pulleys now. Requested an increased idle speed from 560 to 600 in drive, and up to 900 rpm in neutral/park. No idle speed adder with the AC on in drive, versus +24 rpm stock.
thumbsup2.gif
 
Nice gains, you'll need a reprogrammer to take full advantage of the Thermostat mod. Then you can adjust the fan trigger temps to get the temps to stay low all the time.

AC drops them as the fans come on.
 
Originally Posted By: TallPaul
I don't see why it should lose low end torque. Maybe the computer just has to adjust to the new situation.
I agree, there should be a slight improvement in low end.
 
^^what they said^^, engine should spool up a tad quicker. On my 2002 CV with mods/tune, the UD's added to traction issues lol.
 
You shouldn't need a tune for underdrive pulleys. I don't get this at all.
Usually, a smaller crank pulley is the only mod, with maybe an overdrive for the alternator if you have high idle demands.

This frees up power, but it doesn't matter if it is a 1.5L or 5.0L. The accessories are about the same.
The gains are at high RPM - that is, increasing gains. About 5-7 HP if you turn 6,500RPM. A bit less drag at idle, so it might be smoother.
 
Pretty much spot on. On my 98 Neon R/T the pulley setup made a difference you could feel, and as a side effect cured a harsh A/C engagement issue at the same time.

I would think on a big V8 the difference would be very slight if noticeable at all.
 
I have heard that underdrive pullys cause your headlights to dim when at a traffic light because the alternator is spinning so slowly.
 
Originally Posted By: TallPaul
I have heard that underdrive pullys cause your headlights to dim when at a traffic light because the alternator is spinning so slowly.

I never had that problem. I bought a set of march underdrives. You don't need to tune for pulleys so save your money. Buy a tuner,I've got an sct and I'm happy with it and our local tuners use that particular software so no problems getting tunes.
As far as headlights dimming that's a non issue unless there is a serious load pulling on the system.
I only put on the crank pulley and torque was better of the line. Bizarre that you experienced the opposite. Interesting
 
Originally Posted By: TallPaul
I have heard that underdrive pullys cause your headlights to dim when at a traffic light because the alternator is spinning so slowly.


This is very platform specific. While it is possible, no vehicle that I have put them on has had any issues whatsoever. And we use (and have used them) on a lot of our vehicles.

One of the tricks used on my SRT8 is the factory underdrives the crank pulley on the 6.1!
 
possibly free up a little bit of mileage, a bit of throttle response. Most 4 bangers can actually have a noticeable improvement from just a crank pulley.
 
Originally Posted By: TallPaul
I have heard that underdrive pullys cause your headlights to dim when at a traffic light because the alternator is spinning so slowly.


Yes, this is common with UDPs, but generally harmless.
There usually is a slight difference with a stock system, also.

Guys with high powered sound systems use an overdrive on the alternator to get around this.
 
Originally Posted By: mechtech2
You shouldn't need a tune for underdrive pulleys. I don't get this at all.
Usually, a smaller crank pulley is the only mod, with maybe an overdrive for the alternator if you have high idle demands.

This frees up power, but it doesn't matter if it is a 1.5L or 5.0L. The accessories are about the same.
The gains are at high RPM - that is, increasing gains. About 5-7 HP if you turn 6,500RPM. A bit less drag at idle, so it might be smoother.


Agreed, i never heard of a tune from any type of accessories pulleys. Maybe it was mistaking for supercharger pulleys.

The crank pulley has always been one of those things that i've always wanted to try but never did. On the VQ30/Vq35, its a harnmoic balancer, some say replacing them with lightweight pulleys ( normally stock are 3-5lb and aftermarket ones are about 1lb) will not do anything or some will cause vibrations. They normally run $150-250 for my but if there is a chance of better MPG i would be down to try ( never heard of it until this thread)
 
Originally Posted By: bowlofturtle
Originally Posted By: mechtech2
You shouldn't need a tune for underdrive pulleys. I don't get this at all.
Usually, a smaller crank pulley is the only mod, with maybe an overdrive for the alternator if you have high idle demands.

This frees up power, but it doesn't matter if it is a 1.5L or 5.0L. The accessories are about the same.
The gains are at high RPM - that is, increasing gains. About 5-7 HP if you turn 6,500RPM. A bit less drag at idle, so it might be smoother.


I read the same thing about fords 4v engines that came in the cobra's and mach's. Apparently the dampner eliminates vibration at high rpm,which I believe is more important to control than a couple extra hp.
Agreed, i never heard of a tune from any type of accessories pulleys. Maybe it was mistaking for supercharger pulleys.

The crank pulley has always been one of those things that i've always wanted to try but never did. On the VQ30/Vq35, its a harnmoic balancer, some say replacing them with lightweight pulleys ( normally stock are 3-5lb and aftermarket ones are about 1lb) will not do anything or some will cause vibrations. They normally run $150-250 for my but if there is a chance of better MPG i would be down to try ( never heard of it until this thread)
 
Originally Posted By: mechtech2
You shouldn't need a tune for underdrive pulleys. I don't get this at all.
Usually, a smaller crank pulley is the only mod, with maybe an overdrive for the alternator if you have high idle demands.

This frees up power, but it doesn't matter if it is a 1.5L or 5.0L. The accessories are about the same.
The gains are at high RPM - that is, increasing gains. About 5-7 HP if you turn 6,500RPM. A bit less drag at idle, so it might be smoother.



Same thing I was thinking..no need for a tune for this (there is't one anyhow). There is no change in air or fuel or exhaust.
 
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