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762 Posts
Discussion Starter · #1 ·
Just as I promised, here is the data on the Bullitt vs stock GT pulley issue. I also included a comparison of my car's dyno results with 1999 and 2001 Cobras and 1999-2001 GT's. I'm not boasting I just want to hopefully reveal why a Bullitt is more than just a great looking and handling car but a performer as well and thus worth every penny.

(This will be a two parter because my server is being very weird)

As for the question of the pulley size difference; here is what I discovered.

Bullitt water pulley 5.5 GT 5.0
Bullitt alternator pulley 2.50 GT 2.25
Bullitt crank pulley 6.75 GT 6.75

The pulleys were in fact optimized for performance by Ford at the factory as promised. I gained a few more HP and TQ because the BBK kit comes with a crank pulley which uses the stock as a harmonic balancer. It is therefore by default smaller than stock.

<font size=-1>[ This Message was edited by: roushraven99 on 2001-10-25 08:09 ]</font>

<font size=-1>[ This Message was edited by: roushraven99 on 2001-11-28 20:53 ]</font>

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762 Posts
Discussion Starter · #2 ·
Part two: The Dyno Comparisons

Apart from my car all the information presented was taken from articles in 5.0, Super Fords, Muscle Mustang and Fast Fords, Car and Driver; and from BON members.

My car stock (1520 mi) 232.5 HP 266.2 TQ
with my mods 258.6 HP 294.9 TQ

2001 GT stock (new) 225.4 HP 265.5 TQ

2001 GT stock (??? mi) 237.5 HP 276.5 TQ
with Steeda pulleys 242.3 HP 287.8 TQ
Steeda Cat-Back and 17
degrees timing

2000 GT stock (new) 224.9 Hp 265.5 TQ
with shortys, H-pipe 254.1 HP 297.7 TQ
with cats, cat back
chip, and pulleys; all from SHM

2000 Gt stock (10,000 mi) 231.5 HP 280.1 TQ

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762 Posts
Discussion Starter · #3 ·
from 2000 GT stock continued

same car with pulleys 240.3 HP 286.4 TQ

1999 GT stock (>2000 mi) 215.0 HP 261.8 TQ
with pulleys, 70 mm TB 244.7 HP 286.3 TQ
and off-road H-pipe

Now for the Cobras

2001 Cobra stock (new) 266.8 HP 269.5 TQ

2001 Cobra stock (153 mi) 277.5 HP 285.5 TQ

2001 Cobra stock (new demo) 272.0 HP 269.5 T

Almost there 1999 Cobras and conclusion next

· Registered
762 Posts
Discussion Starter · #4 ·
1999 Cobras

Stock 238.1 HP 251.2 TQ
SVT fix 262.6 HP 269.6 TQ

stock 238.9 HP 252.3 TQ
SVT fix 265.0 HP 266.0 TQ

stock 239.2 HP 252.7 TQ
SVT fix 263.6 HP 269.7 TQ

Okay, what does all of that prove. Well honestly without more Bullitt dynos it theoretically doesn't mean anything. However, I don't believe that my car is statistically different than any other Bullitt. Having said that I believe it shows that Ford did give us what they promised even if they don't admit it officially (maybe to protect themselves in the case a few don't perform). Nonetheless, when I an owner can add less than $2000.00 in bolt ons and be near or better than the revered SVT with a package as complete in looks, handling and desireability as we have with the Bullitt; then my friends we truly have something special and worth in my humble and opinion (and that of others) is worth every penny.

My plots can be seen on

Questions ... Comments???

<font size=-1>[ This Message was edited by: roushraven99 on 2001-10-25 08:12 ]</font>

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50 Posts
More great post Roushraven99. I like the black vert., but I have Roush screan saver that has a canary yellow vert that I'd like to see sitting next to DHG.

· Registered
959 Posts
Roush...thank you for the great information. Your data agrees with my butt dyno that these cars make great torque. Looks like to optimize the pulleys, just adding the crank pulley should give us some additional reduction. Great job!


· Registered
22 Posts
Great info Roush!

By RPM here's how your Bullitt compares to a slightly modded 99 Cobra (flowmasters & K/N).

At 2500rpm the bullitt has +2.6Hp,+5.6Tq

3000rpm the bullitt has +9.7Hp,+17Tq

3500rpm the bullitt has +8.2Hp, +12.8Tq

4000rpm the bullitt has +4.3hp, +5.6Tq

4500rpm the bullitt has -0.3hp, -0.3Tq

5000rpm the bullitt has -11Hp, -11.6Tq

5500rpm the bullitt has -34.1Hp, -10.3Tq

6000rpm the bullitt has -67.4Hp, -1.9Tq

So until about 4500rpm a modded Bullitt has an advantage over a relatively stock '99Cobra.

· Premium Member
8,327 Posts
Thanks Blue BYU,

So it does tend to show the advantage that RouschRaven's Bullitt will have at the low end of the curve. Sounds like the Bullitt is a decent buy for the price. :smile: The Cobra really starts to hit its stride @5000 rips eh? The difference really starts to show at that point.

Thanks for continuing to reinforce our buying decision. :wink:

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762 Posts
Discussion Starter · #9 ·
Thanks from me too BLUBYU,

It's great to see for comparisons sake what the two are like. I pretty much knew the advantage of the 4V was its ability to rev higher. Still it's satisying down low and off the line which is really appreciated in city/highway traffic. As for the strip I wonder if MM&FF will do one of their infamous "shootouts" that would be really interesting. But then again wouldn't it be even better if we both could be this close in comparison to our GM rivals. Anyway, I know I'll enjoy the car as I'm sure you're enjoying yours. Anyone have a treatment for me 'cause I'm suffering withdrawal symptons as I wait for it to arrive over here and the engine of my Roush is at Powertrain for stronger pistons, rods, and crank as well as some head work?
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