08'MustangDude

Believe what you want, you will see one day how wrong you were about UDPs adding
BHP. The engine is 320 HP, at the crank, changing the pulley doesn't change THAT.
It will increase RWHP because you freed up some of that BHP by reducing the parasitic
dreag/loss at he accessory pulleys.

Still, I DARE YOU, remove your serpentine belt, and DYNO the car, with the factor crank pulley.
Replace the factory crank pulley with a UDP, leave the serpentine belt off, dyno it again. You
won't see ANY increase in HP. I DARE YOU, do it... You won't, because you will be proven wrong.

That's like saying, you get $300 gross in pay, with $210 NET after the taxes (parasitic loss).
Now, adjust your tax rate so less taxes are taken. Well, you didn't GROSS more money, you
just freed up some of that gross into your pocket (NET)... That is EXACTLY how UDPs work.
Underdrive pulleys increase engine's output by reducing the draw of the engine's accessories by
slowing them down and reducing the HP they use. That freed up HP ads to RWHP, not BHP.

Underdrive pulleys divert otherwise wasted BHP away from the accessories, like the water pump,
alternator to drive the crank faster, making more RWHP. They do not ADD BHP.

One day, when you wise up, you'll see... RWHP is not BHP, no matter how you slice it. When
you DYNO your own car, with no serpentine belt, with OEM and UDP, you'll see, there is no
increase in HP. You will see RWHP go down when you put the serpentine belt back on, with
either pulley, just that the UDP will not be as low.

Dino Dino Bambino

Never mind. I give up!
You still want to believe that underdrive pulleys only increase HP measured at the rear wheels (RWHP) and not HP measured from the rear of the crankshaft (crank HP). In other words, you're implying that UDPs reduce drivetrain HP loss despite the fact that they're mounted at the front of the engine!

Regardless, UDPs will add 8-10rwhp, make your car go faster, and give a slight improvement in gas mileage which is what the OP is looking for.

Dino Dino Bambino

Here's some interesting reading for HP junkies:

https://www.dynomitedynamometer.com/...horsepower.htm

https://ateupwithmotor.com/terms-tec...et-horsepower/

08'MustangDude

PROOF IS IN THE TEST!

Remove the serpentine belt, keep the factory crank pulley on, DYNO the car.
Replace the crank pulley with the UDP pulley, leave serpentine belt OFF, DYNO the car.

You will not see an ADDITION of horsepower, PERIOD!

You said it (UDP) ADDs horse power, so, the dyno should show an increase in horsepower
when you replace the factory pulley with the UDP pulley. It will not, and you can take
that to the bank.

pascal

Putting cams on, long tubes etc... is by then more costly than going with a centrifugal blower like Vortech or similar.
Not to mention that you'll have more than 400 ponies at the wheels...
After 350 hp on these engine, a supercharger makes the most sense IMO.

Dino Dino Bambino

Duh! If you leave the serpentine belt off for both dyno tests, of course you won't see any change!
The whole point of having underdrive pulleys is to have the belt in place to drive the accessories at a reduced speed, and it's the reduced operating rpm of the accessories that consumes less HP.
You obviously don't have a clue what you're talking about and you're making a pointless argument.

Dino Dino Bambino

I totally agree.
The way I see it, the two most cost-effective options are:

1. N/A: Stick to the basic bolt-ons i.e. CAI, CMDPs, UDPs, off-road midpipe (if legal in your state), custom tune, and settle for 310-315rwhp (manual tranny) or 355-360 crank hp.

2. Choose forced induction from the outset with a self-imposed 460rwhp (manual tranny) or 525 crank hp limit since the short block will remain stock. The Department of Boost GT450 intercooled supercharger kit costs ~$4500 and can be installed by a competent DIY mechanic plus assistant over a weekend.

08'MustangDude

YES, so they DO NOT ADD HORSEPOWER like you said, no, like you INSISTED. They
increase RWHP, not BHP, as I said three times, or more.. Glad you finally see it...

I also mentioned all that other crap you have there too, you missed it somehow...

Dino Dino Bambino

You need lessons in reading comprehension!
​​​​​If you run a car on a chassis dyno with NO drive belt and the stock crank pulley, and run it again on the same dyno with NO drive belt and an underdrive crank pulley, there won't be any increase in RWHP either!
Get it?
Tell me. What idiot would install underdrive pulleys and run his engine without a drive belt? Your whole argument is making you look foolish.

​​​​​​Read this:
https://en.m.wikipedia.org/wiki/Underdrive_pulleys

08'MustangDude

The entire argument is you saying the UDP adds BHP horsepower, they do not. I know how
they work, WHY they work. I work in a PERFORMANCE SHOP, and we only work on high
end vehicles. The entire point in dynoing the car without the drive belt with the UDP is to
PROVE they DO NOT add BHP horsepower.

Also, hell yes it would increase RWHP without the serpentine belt! Since the UDP would
reduce the parasitic loss, allowing more BHP to RWHP in the FIRST place. Running without
the belt you will get the most RWHP you can, because there is no belt installed to drive any
of the pulleys. If I build a 1/4 mile drag car, it will have an electric water pump, and manual
steering. The only belt you're going to see is the one driving the blower.

For a daily driver, you settle with a UDP, that does not ADD BHP, it will simply add to your RWHP
with the reduced drag at the accessory pulleys. YOU kept right on saying that they ADD horsepower
TO THE ENGINE, and they don't, they never did, and never will.

I never said drive without a serpentine belt, I said, for DYNO testing, not to be taking mommy
to the grocery store to pick up her preparation "H". Show me anywhere I said, drive around without
a serpentine belt. I said to prove they do not ADD BHP, Dyno it that way. I didn't say, drive mommy
to Giant Eagle while doing the test. You said all that, not me, so I am not the fool here. Dyno
testing is not driving around town...

Increasing engine output is not increasing BHP, else it would indicate that, specifically. It is a play
on words to fool people like you into thinking that it adds BHP. I can increase engine "output" by
changing to lighter weight body panels, and/or tearing everything out of the interior except the driver
seat. I can use lighter alloy rims, and even use lighter accessory pulleys. I did not say doing that
increased engine HORSEPOWER, just output, which is to the wheels, another play on words to
fool you. They want people like you to assume "output" is to the crank, and look how it worked,
you took the bait and are slinging it everywhere.