[JayP]

Alright, as luck would have it, the car right before my Bullitt was a 2001 GT. I was early for my appointment and I didn't know the previous group.

That GT pulled somewhere around 230 to 235 hp. Torque was in the mid 260s. I tried to remember, but I just got there.

When they found out my car was a Bullitt-- there was interest in what my car could do.

My first run was 234.9 and 268.4... LESS than the GT!! I don't know if they modded it, but I suspect the only mod -might- have been a filter. (Yes- I'm making excuses.) My car has 5500 miles, so its broken in.

When the throngs of watchers saw the low numbers... they "Had seen enough." Crap.

The third run was 239.5 and 274.9 (guesstimate of 15% makes that 275.4 and 316. Expected numbers, maybe a little better).

Comparing the GT to my Bullitt, it was close, even giving the nod to the GT for Max HP and torque.

But... my power and torque curves are --flat-- from 2200 rpm, I have 255lbft. 2200rpm is practically at idle. The GT's powerband was nowhere near as flat.

I had way more area under the curve than the GT, but lost to peak HP.

 

[roushraven99]

JayP
FYI looks I don't see where even the GT's peak numbers were better than your posted best. In any case factoring the accepted 15% drivetrain loss your stock car is making 281.7 FWHP and 323.4 FWTQ very good in my book.

 

[01GTB]

At 5500 miles your car is not broken in, IMO.

The fact that it does not make any more peak horsepower is not hard to believe. People line up expecting some big numbers that just blow the GT's out of the water, it's not going to happen. Then they walk away dissapointed as it seems the guys watching did. Yeah, it would be great if it was an under rated factory lightweight that pulled up and clicked off 270 rwhp and would bust some 12.80 1/4 miles, but it isn't. It is a GT and it performs like one, with a few added touches and maybe a little torque through the power band. This is one thing that sucks when they hype a car the way they did the Bullitt. People don't grasp the whole picture. They think if you pay more and don't get more horsepower, you have a POS. I knew this was gonna happen before I bought mine, I say screw em! End of Rant :grin:

 

[JB VOBRA]

<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font size=-1>Quote:</font><HR></TD></TR><TR><TD><FONT SIZE=-1><BLOCKQUOTE>
On 2001-09-09 01:52, JayP wrote:

That GT pulled somewhere around 230 to 235 hp. Torque was in the mid 260s.

The third run was 239.5 and 274.9 (guesstimate of 15% makes that 275.4 and 316. Expected numbers, maybe a little better).

Comparing the GT to my Bullitt, it was close, even giving the nod to the GT for Max HP and torque.

</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR></TD></TR></TABLE>

this is confusing: you pulled 239/274, but the GT gets the nod for max hp/tq??

And btw...this is how you calculate crank hp/tq from rear wheel figures:

rw # / (1.00-.15)
239 / .85
281 crank hp

275 / .85
323 crank tq

Your peak pull is right in line with my dyno numbers. However, I've never had such big swings in consecutive pulls. They have all been within 2rwhp/2rwtq with the first pull always netting the best of the day. These modular motors do not like heat.

 

[Mid Life Crisis #388]

Hey JB, so you /.85 I had been X 1.15
Looks to be almost 5hp difference.

If thats right, (And I believe you) then from what looks to be the average dyno tests I have seen the Bullitt is averaging around 280+
Sound right to you?

 

[JayP]

I might be able to find out who's GT that was. The GT spiked in a few places in all 3 runs. The operator put my 2nd run over the GT's best. The GT had more HP. I can't remember the exact numbers. I just remember that I made less than GT.

The GT was either right there or better, and the low numbers on my first run compounded that... it looked bad.

Also- The car was outside, noontime Texas, so it was hot. They brought the car in, put a fan ot it and let it sit for about 5-10 minutes. The first run was the lowest. The 3rd the best with about 5 minutes between trys. Everyone made more power the longer they were in the garage.

<font size=-1>[ This Message was edited by: JayP on 2001-09-09 18:55 ]</font>

 

[JB VOBRA]

well, look at it this way:

for example, you have a known rw hp number like 240. If you're assuming a 15% loss, and you calculate the crank hp like you were: 240 X 1.15 = 276. Now try to get back to the rw number with the calculated crank: 276 X .15 = 41.40 drivetrain loss so 276 - 41.40 = 234.6. You're 5.4 short (234.6 - 240) of the known rw.

Now here's how I do it. Take the 240 / (1.00-.85) = 282.35. Now take the 282.35 X 15% = 42.35 and finally 282.35 - 42.35 = 240. It works in both directions; rwhp to crank and crank to rwhp.

Regarding the 280 crank average for most Bullitts, that would require a rw dyno of 238 (280 X .85). From what I've seen in person and on the internet (seen some in the high 220's), I'd say that isn't correct. It's probably closer to around 234rwhp, which btw, would put the bullitt figures exactly were Ford had originally released....(234/.85) 275 crank.

 

[Gibscreen]

One of your formulas is off JB Vobra.

You said take the RWHP/(1.00-.85) to get the crank hp.

It's actually RWHP/(1.00-.15)
Or an easier way, just RWHP/.85

And then to go from crank to RWHP, use: CrankHP x .85

Those both get you the same numbers, and they're easier.

But I actually have to take issue with the whole 15% drivetrain loss. Of course it's an assumption, and not meant to be exact. But it seems like using the 15% gets everyone more than the factory claimed 265hp. Now I know Ford, and if anything, they overestimate power. So I find it hard to believe that they would underestimate it at 265, especially after the backlash they received after claiming that the Bullitt was making 275. They wouldn't have bumped the numbers down to 265 unless they were absolutely sure it wasn't making more than that. So if most people are running about 235 RWHP, it seems like it would be about an 11 or 12% loss. This brings it to about 264-266 crank hp.

 

[Mid Life Crisis #388]

This has been brought up before, the Ford site now quotes the Bullitt at 275 HP and 315 FT
http://www.fordvehicles.com/cars/mustang/models/

 

[JayP]

Here's the latest-- I found the GT.

http://www.bullittclub.com/phpBB/viewtopic.php?topic=2136&forum=9&0

 

[Gibscreen]

Did the Ford site used to say that the Bullit only made 265 hp and 305 tq?

 

[JB VOBRA]

<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font size=-1>Quote:</font><HR></TD></TR><TR><TD><FONT SIZE=-1><BLOCKQUOTE>
On 2001-09-21 01:13, Gibscreen wrote:
One of your formulas is off JB Vobra.

You said take the RWHP/(1.00-.85) to get the crank hp.

It's actually RWHP/(1.00-.15)
Or an easier way, just RWHP/.85

And then to go from crank to RWHP, use: CrankHP x .85

Those both get you the same numbers, and they're easier.

</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR></TD></TR></TABLE>

well, that was a typo. I was just trying to demonstrate the formula before just plugging in ".85". I meant to put 1.00-.15 to show the drivetrain loss(or whatever loss you want to use .10 or .11 or .12, etc..)

If you look further in my post I did just simply use the .85 factor.