How Much Horse Power GT500
 

Question:
How much horse power does it take for a Shelby GT500 to go into the mid 11's in the 1/4??

Anybody...:dunno:

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my guess 750
650 for low 12's,....

Willie might have a good estimate.....I will ping him.

This post is on another board.......
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Well I finally made it to the track with my 07 coupe. It has the Evo Tvs stage 4 kit and a Steigmeier reworked supercharger.

I tried a couple of runs and really sucked, I am used to 12 sec cars and have never ran something like this. I was blowing off the M/T 305/35/18's on every run. At the line and after shifts. I even did huge burnouts to heat the tires. I was a little discouraged because I knew the car had the potential in it. I also was using Evolutions 93 octane tune instead of the race tune to tone it down a little.

Lucky for me some people from the Midwest Mustang Owners Association were there.

Greg was working the starting line and was giving me some pointers. A Chevy Chevelle just had puked it's tranny so we were down for clean up. I said to him......do you think you could do better? He said he could give it a try. I said lets do it ...you drive. He seemed kind of shocked but I told him don't worry short of crashing you couldn't hurt it more than I have.

Greg went out and on the first pass went 11.615 @ 129.51...wow...and that was not a perfect run! I said do you want to try again and he said why don't you ask Mark " a Cobra owner" if he would give it a try.

The first pass out Mark turns a 10.788 @ 132.99. I almost fell off the grand stands! He had some traction issues but really drove it well to say the least!

The track guys were not happy and wrote on the slip Cage/5pt Harness/Fire Jacket. I was kind of amused because when I went through tech the guy said it looks pretty stock have you done anything? I said I just put on a Ford racing upgrade supercharger...he says go have fun!

Mark was impressed with the car, I said do you want another try to see if you can do better? He said that Dan who runs a mid 9 sec Fox body would be the guy to give it a try.

Dan agrees to see if he can lower the time a little more, he looked to have a good run going but about at the 1/8 mile mark the car lost traction and started to go a little sideways. He was still able to run 11.244 @ 131.75. That run ended it though as the time slip had written across the top "Done For The Day!"

Well the reason why I ask is because I just turned a 11.67 @ 120 mph on Saturday, California Speedway with just a few bolt on's... I have never dynoed my car so I have no idea how much horse power I am putting out. A lot of people came up to me to congratulate me on my 11 second run and then ask me what I have done to the car. When I told them the mods, they would look at me like I was lying...lol They could not believe that a 4000 pound car could run those times with the few simple bolt on's. Me Included...lol !!!

I ran four 11 second runs in a row, so I know its not a FLUKE !!! Can this be possible ???
Look for yourself...:ohmy:

http://www.motorgen.com/vid/showphot...4/limit/recent




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There was a guy that had full suspension, full exhaust, and I think a Stage 2 kit that ran a 10.50 on slickshttp://www.teamshelby.com/forums/index.php?showtopic=14352&hl=

How much horsepower was he putting out? That's what I would like to know...
All I have on my car are simple bolt on's. JLT CAI, 91 Tune, 2.6 pulley, and 2.5 exaust.
The rest of the car is bone stock...stock 3.31 gears, stock suspension, stock everything else...

You have a 91 tune? Doesnt the GT500 require 93 from the factory for the blower?

Shouldn't you have 3.73 gears? :dunno:

In California the Highest octaine available is 91





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Car came with 3.31 gears from the factory...I believe some did come with 3.73 gears.





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Well the Evo stage 4 is different than when that guy did it. They have since added the bigger throttle body and the 10% lower pulley. It says that it will add 231rwhp. So if I were to add that to my car at 473rwhp, I'd be at 704rwhp, which I think is a little higher than what I'd actually be at, but lets say that's correct then lets go back and subtract out the throttle body and 10% lower pulley from the equation which should account for roughly 65rwhp so that puts us around 639rwhp. So essentially with that rwhp and slicks and 4.10 gears, if you can drive the heck out of the car you should be able to make a low 11 or 10sec pass. Now from what I've heard the guy that did those times, was one hell of a driver. But then again Evolution Performance had apparently done it before him.

Only the KR comes with 3.73 gears all other are 3.31

Only the KR comes with 3.73 gears all other are 3.31

So 639rwhp is what is needed to make a mid 11 second pass? My car has the stock 3.31 gears though, not the 4.10's.... As far as driving...I like to think im an OK driver




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My buddy who I sold him his 08 GT500, got both pullies done, suspension, CAI, and a EVO tune, and he's approximately at 615 rwhp. He took it to Atco, for the NMRA back in August. He only got 1 run in before the downpour that Sunday. He texted me, as I was at a different car show, and told me he did 12.2 and it was, as he put it, an easy pass. His reaction time was crap as he said, and he basically took it easy to see how well the car would hook first, before giving it hell the next pass. Ultimately though, the rain came, and no 2nd pass. It was the 1st time he used the 305 M/T radials and wanted to get an idea before going all out. I know he can do a low 11 second run, as our friend who has a Whippled '07 GT ran 11.71, and only has 468 to the rear. I was hoping he could join us at Cecil next Saturday for the SSOTN open track, but he's gotta work. :( Would love to see that car do low 11s!

There is a lot of more factors that go into it then hp for drag racing. you could lighten the car and put slicks on a stock gt500 and get an 11 sec slip.

Wow! Even the Bullitt has 3.73 gears. I'd change that real fast.

Yeah I'm going to add 4.10 to my car in place of the 3.31's.

No 91, many parts of the US can't get 92 or 93...

From The GT500 Owners Supplement...

http://forums.bradbarnett.net/attach...1&d=1225933334

OCTANE RECOMMENDATIONS

Your vehicle is designed to use “Premium” unleaded gasoline with an (R+M)/2 octane rating of 91 or higher for optimum performance.

The use of gasolines with lower octane ratings may degrade performance. We do not recommend the use of gasolines labeled as “Premium” in high altitude areas that are sold with octane ratings of less than 91.

If your engine knocks under most driving conditions while you are using fuel with the recommended octane rating, see your authorized dealer to prevent any engine damage.

Exactly...which brings me back to my original questions...My car had full interior, even the shaker in the trunk. Stock wheels in the front. Nothing was done to make the car lighter.

How much horse power does it take to make a GT500 do mid 11's ? :dunno:



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I thought about the 4.10's but I don't know if its worth it for my car. I'm already pulling 1.778 60' times. There were a few mustangs that day that had 4.10's and were pulling the same 60' times...lol

There was an 03 Mach 1 with 4.56's and was only pulling 1.635 60' times...:confused:



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Something I really have to think about...:wonder: I do drive my car on the highway a lot. I like the fact that I can cruise at 65 mph in 6th gear and only be doing 1800 rpm's.






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Depends on where you have to shift with four tens. If your shifting at the stripe there is no point.

Roger

I'm just following what most of the big shops have done for gears.

CooBra07 you could step up to 3.73's and it wouldn't make a big difference on your RPM's. A lot of guys on TeamShelby.com recommend gears as a first modification.

Be careful with your gear choice
 

Be careful, this guy is running 4.10/1 gears and they were too low, he was having to shift into 5th in the 1/4 mile. His solution was to get the tallest MT drag radial tire he could P305/45R18.

He still has to launch at 1800 RPM.

BTW:
He is running 11.43 @ 127.24

http://glasshousefarms.com/cars/GT500Drag/


Just a few random gear related thoughts...

I like being able to drive a 500 horsepower car on the street that is quicker than most and still consistently gets over 22 miles per gallon on the highway.

Since you can exceed every speed limit in the USA in second gear doing 80 MPH with the 3.31/1 gears, lower gears would be more fun on the street. For the 1/4 mile I believe 3.73/1 or 3.90/1 would be the ideal gear ratio. Coincidently, Shelby seems to think the 3.73/1 is ideal.

Yeah...If I was contemplating a gear swap I think I would go with the 3.73's instead of the 4.10's.




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That is an awesome looking Shelby ! How much horsepower is he putting out? Do you know what his 60' times are.? He's running 11.43 in 1/4 with the 4.10s....thats makes him 2 tenths quicker than my car and I'm running the 3.31 gears, though he is running 7 mph more...

Something is just not making sense:banghead:




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You're asking a basic physics question. HP is a simple calculation if you know how much weight was moved over a known distance in a known amount of time. So, to answer your question, a 120 mph trap speed (what you ran) in a 4,000 lb car (your car w/you in it, right?) requires 475 RWHP. Assuming a 15% drivetrain loss, that 475 RWHP equals roughly 560 HP at the flywheel.

On a side note, with proper gearing and traction, your 120 mph trap speed indicates that your GT500 could run 11.30's without adding any more HP.

JUST FYI....HAVE FUN:D
http://www.dragtimes.com/horsepower-...calculator.php

I would think it should only take around 500rwhp to get into the mid 11's. A Supercharged GT with between 450-500rwhp and get into the 11's

just get it dynoed and you'll have your answer. awesome time btw with the minor bolt one's you have on it now.

100# = 15 Horsepower
 

Hum, according to that calculator 400 extra pounds takes 60 extra horsepower to move to the same 1/4 Mile Time & Trap Speed...

100# = 15 Horsepower

1/4 mile time: 11.43
Trap Speed: 127.24
Weight of vehicle
with driver (pounds): 3600
Horsepower @ flywheel = 527.65 HP

1/4 mile time: 11.43
Trap Speed: 127.24
Weight of vehicle
with driver (pounds): 4000
Horsepower @ flywheel = 586.27 HP

If you compare the cost and effort of dropping 400 or 800 pounds versus adding 200 or more horsepower to these mod motor Mustangs, adding horsepower is clearly the easier way to go...

Case in point: my supercharged 07 GT automatic coupe only puts down 351 rwhp, yet goes 12.30's at 111 mph in the 1/4 mile. Another 100 rwhp and mid 11's would be a given.

The stage 2 Kit according to Evo w/ 93 octane tune adds 145 RWHP.
Factory RWHP is what 450?
450 + say 120 since you have 91 octane = 570 RWHP.
Remember, you're close to sea level (compared to some) so that helps a bit.
I have the same kit as you do. 3.31 rear is factory and I have 91 only octane.
No dyno sheets right now. Sorry.

A GT supercharged is much lighter then a GT 500.

ote=o7 tungsten;5676326]just get it dynoed and you'll have your answer. awesome time btw with the minor bolt one's you have on it now.[/quote]


Thanks...the car is fast with just the bolt on's that I have on it now, I think my next mod will be the botton pulley which should give me about 4 more pound of boost.

If I do that I will have to get the car dyno tuned...





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Thanks for that but, I am getting different numbers with this ET Calculator..

Check it out >>>http://www.rpmoutlet.com/dyno.htm


according to the calcualtor im putting out 539rwhp...

your ET Calculator says im putting out 518 FLYWHEEL hp...:mad:



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Wow...that translates to some nice hp to the flywheel. I have pretty much the same bolt on parts from their stage 2 JLT combo package...the only thing I don't have is their tune.:D



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I tried Evo, VMP and Brenspeed tunes and brenspeed by far seem the most responsive. My car came from out east so, it may have been tuned for a different altitude and octane with the Evo/VMP tunes I'm nto sure. The Brenspeed was a mail order update.

Does your supercharger come on about 3000 rpm's when reving in neutral?

Try 570 with the calculater..is it close?

I think 540 rwhp is much closer.

The supercharger comes on at around 1500 rpm...Is that to soon???




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1500 if it's in gear with a load (heavy acceleration) then maybe...

ok on 540!

On your clips, are you in 3rd at the 1/4? You get a good launch without wheel spin.

Nope, that's 1500 in neutral...it actually may be sooner than that. If the car is just idling and I punch the excelarator the boost gage moves right away.

Yes, I am in third when I go throu the traps at around 6300 rpm...

Even though I have the M/T cheater slicks (wich work great!) I do still get some wheel spin. I do have an in car video of my 11.67 run, I'll try to post it today...Let me know what you think.

If you listen you can hear the tire spin. :( I still managed to get a 1.8 60' time. On my 11.73 run I got a 1.7 60' time, there wasn't much wheel spin on that run.



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Check It out, in car video of the 11.67 run :D

Click Here


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Wow- cool in car! You can see how much the car shakes and your head moves when shifitng.
1) what's the audio that I hear?
2) what do you mess with under the steering wheel?

I'm no expert but looks like you're doing everything right.

Yeah ... I did not realize how much my body moved around until I saw the video. I must say, not only was it a fast run, it felt really fast inside the car! The car pulled hard all the way down the track. It was my first time at the track with the new 2.6 pulley.:D

1) The voice you hear is the announcer, I like to keep my radio tuned to the tracks FM Station to hear whats going on. Sometimes the announcer says the ET's over the radio, that way I don't have to wait to get to the time slip booth to know what my times are. You see me turn up the radio right after I let off the gas.

2)I installed the line lock switch under the steering wheel. There is a nice flat spot perfect for the switch. Out of the way and out of sight. I would hate to make a hole on the dashboard or center console, when I'm not racing I tuck the switch underneath the dash, no ugly switch or empty hole to see.:nice:

Did you happen to notice the tire spin? We are talking about 3.31 gears...car has a lot of torque, I can imagine if I had 4.10's

Did you also happen to notice that I launch the car in idle...I hit the gas right before I let out the clutch...that seems to work for me. I tried to launch the car at 3500 or 4000 rpm but tires always seem to break loose.

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Check this picture out...see if you can zoom in on the rear tire. You can see the tire wrinkle.

yeah, it's under some torque there. Did you win the vette race?

Wondering if the tires are warm enough after the burnout?

Somone I know tried 3.73's and thier ET went up.

Next up is to get some weight out of the car somehow.

What about Steeda UCA & LCAs and alum driveshaft?

There will be a dual core intercooler available in the next 3 mos that will lower inlet air temp 70 degrees.

Yes...I won that race...I ran an 11.94 vs the corvette ran 13.1

I always try to make sure I get a good smokey burnout..

The person you know with the 3.73's made the car slower? How did that happen! My goal is to get low Et's not higher...:doh:


Have you ran your car at the track yet?



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3.55s and 3.31s
 

[quote=CooBra07;5674999]Something I really have to think about...:wonder: I do drive my car on the highway a lot. I like the fact that I can cruise at 65 mph in 6th gear and only be doing 1800 rpm's.




I have an 05 Mustang GT with the Shelby wheels and tires on it, 3.55 gear and I tach 2000 rpm at 65. I am not sure the final drive ratio comparison of my 5th gear to your 6th gear but maybe you do have 3.31s? Thats what I have heard

All 2007-2009 GT500s come with 3.31/1 rear end gears.
The GT500KR's all come with the same 3.73/1 rear end as the 2008-2009 Bullitt.

Here are the Gear Ratios for both transmissions:
Bullitt & GT Tremec TR-3650 5-speed manual transmission

1st Gear: 3.38:1
2nd Gear: 2.00:1
3rd Gear: 1.32:1
4th Gear: 1.00:1
5th Gear: 0.675:1
Reverse: 3.38:1


GT500 Tremec T6060 six-speed manual
Gear Ratios
1st Gear 2.97
2nd Gear 1.78
3rd Gear 1.3
4th Gear 1.0
5th Gear 0.80
6th Gear 0.63

Here are a few photos of my speed and RPM:

Just under 65 MPH is just under 1800 RPM
http://forums.bradbarnett.net/attach...1&d=1222242647

55 MPH @ 1500 RPM
http://forums.bradbarnett.net/attach...2&d=1222242647

Cool on the vette!

Have not run my car at the track no immediate plans for that. Possibly a dyno run.

3.73, you gotta shift again 3 - 4 before the 1/4 mile is up. Difference in ET is lost in the shift.
At least this 1 persons experience.

Black GT500...Thanks for the great pics of the speedo and tach to help me proof my point. I also noticed that you are getting great MPG...If i baby my car and drive the speed limit It actually shows that I am getting 24.2 MPG...don't know how accurate it is!...lol



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With 3.73's im sure I would have to shift into 4th...better reason to stay with the 3.31's. If I was putting out 650 rwhp then I would think about the gear swap to the 3.73's

im going throu the traps in third gear at around 6300 - 6500 rpm's...doing 120 mph.:jester:

Is your Shelby Stock?


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Just remember these motors don't like high RPM's.

What do you consider the max safe rpm?

Coobra - I have the JLT stage 2 kit with brenspeed and borlas.

I'm up to 960 miles as of today,,,,,,

What do you mean...Why don't they like high RPM's????:dunno:




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For me staying under 6500 rpm is safe...and I say this because if you look at a lot of the vids of speed shops doing dyno pulls of GT500's, most seem to run the dyno pulls to 6000 - 6500 rpm's...that's basically what I am doing when I go down the drag strip...simulating a dyno pull in a sense.


awakeinAZ: I have the JLT CAI Stage II kit as well from Brenspeed. You can't go wrong with that setup, your looking at a High to Mid 11 second car...with some good tires of course. See the pic on my sig "M/T's at work", zoom in at the rear tires.


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Went to GTR in Ontario, CA and finally got my car dynoed...

best of three runs was 511rwhp with 505 tq...

So there is the answer to my question...How much horse power does it take to make a Shelby GT500 run mid 11's in the 1/4.

and the answer is........... "511 rear wheel horsepower":nice:



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