I went to the dragstrip in Milan MI yesterday. Here are the results:

[GreenS550]

He's also shifting at a point that engines already peaked 6-700RPM earlier. Dynos show HP peaking between 7000-7250. By 7800 you're making as much HP as you do at ~6300, but with about 50-60ft-lbs less

Peak TQ is at 5000. So to hit that you need.
7700 1->2
7400 2->3
7200 3->4

To hit where the graphs cross(5250rpm) you need.
8100 1->2 (rev limiter basically)
7750 2->3
7470 3->4


Shifting at 7800 every gear not only means you are well past peak HP, but you are shifting into TQ that is already dropping off. In either example 7800 in ever gear is just to high.

I'd try right at rev limiter for 1-2 and just under 7800 for 2-3, then try 7700 1-2 and 7400 for 2-3.

Likely also, if on stock rubber, getting some spin on both shifts.

I hav already explained that I have a tune from Steeda. The numbers do no lie. The car with the tune makes more power at 7800 or so.

Sponsored

 

[OvalBlue26]

Interesting comments all around. But, anyone that thinks they know their 1/4, 60 ft, etc without going to the dragstrip are going to see the truth when they go to the strip. I saw the 1/4 mile times from C/D, MT, etc. I do think with some practice and messing with the launch and tire pressure the car could do high 12's. But, I do not for a minute think this is a 12 second car stock tire pressure, etc. I have no idea where the magazines got their times from, but would love to see the actual slips.

I have been drag racing for 45 years and not just some kid on the street. At the dragstrip where it is real and there are time slips. I did not and do not power shift. I stand on the fact that shifting out of 1st at 51 mph is ridiculous. I also realize that there are better drivers than me. I am really irritated with the track management that day. Very slow considering the small number of cars. With my '11 I was hitting my 1/4 mile times within a 1/10 second consistently. But it takes time.

I am thinking that these are the perfect gear ratios for a PD blower which I'm installing within the next couple of weeks. Arriving on Monday from Whipple.

Let us know how the Whipple install goes, i think quite a few of us are looking at going this route.

 

[Schwerin]

I hav already explained that I have a tune from Steeda. The numbers do no lie. The car with the tune makes more power at 7800 or so.

It makes more than stock but not enough to justify 7800 shifts. The power peak RPM's are almost identical between tuned and not tuned. Go look at the video STEEDA made and GoneIn60's dyno video(also done by the Steeda tune developer) both drop off after 7100-7250 RPM. Look at the screen grab, that's a steep drop off after 7250 even in Steeda's own video.

 

[The Rooster]

LOL.. love the pot stirrers trashing based on the results of one car, on one day, one driver. Yup must be a total dud shitbox pig turd.

THAT said........

13.20s...... either something wrong with the car or more likely (no offence) the way it was driven. Driving this IRS car at the drags is a lot different than the solid axle hotrods that we're all used to. Time was lost getting off the line when you were wheel hopping.. and time is lost if you weren't power shifting. Its a mid 12 second car in the right hands.

....But if 1/4 mile performance is your measuring stick for what makes a good car there's lots of better options out there than the bullitt. one being a base gt with the a10, its whole lot cheaper and it'll dust the Bullitt in the quarter. Or how about a kia stinger?...

Personally I prefer three pedals, full options, and the look of my car over a few tenths on a race track I might find myself on once.

 

[Jetnoise]

It makes more than stock but not enough to justify 7800 shifts. The power peak RPM's are almost identical between tuned and not tuned. Go look at the video STEEDA made and GoneIn60's dyno video(also done by the Steeda tune developer) both drop off after 7100-7250 RPM. Look at the screen grab, that's a steep drop off after 7250 even in Steeda's own video.

Hope your having fun with your car!
Curious as to a single dyno pull vs 3 consecutive pulls( 1st-3rd gear) in 12 ish seconds...think that may play a part in this? Did you modify anything else to help support 7800 rpm?
Your 60' /launch technique is holding you back ? and your mph seems lite...for the hp think?
will Steeda re-evaluate your data log for you?

 

[Schwerin]

Hope your having fun with your car!
Curious as to a single dyno pull vs 3 consecutive pulls( 1st-3rd gear) in 12 ish seconds...think that may play a part in this? Did you modify anything else to help support 7800 rpm?
Your 60' /launch technique is holding you back ? and your mph seems lite...for the hp think?
will Steeda re-evaluate your data log for you?

Think you quoted the wrong person? My post is just to show that power has dropped off by 7800rpm.

 

[Jetnoise]

Think you quoted the wrong person? My post is just to show that power has dropped off by 7800rpm.

My bad
I'm sure op will figure something out

 

[SVTchris]

Based on OP's time slips, this car clearly makes enough power (MPH) to be a 12 second car but until 60 ft. times get under 2.0 seconds, it's ET's will stay above 13 seconds.

 

[Shipey]

Yes! Thank You. I had one on my auto '15. Worked good. Somehow I thought the Magneride might help out here. No difference really.

Wheel hop under heavy acceleration is a known issue with the S550. Note the number of vendors offering improved vertical links, bushings and braces to stop the hop. A huge amount of et will be lost without traction. Also, without careful parts selection, you’ll get unwanted NVH. As far as magazine testing goes, you could be looking at numbers laid down by a professional driver on non-stock tires and the car could be a ringer. That was quite common in the 60’s. Yes, I’m that young!

 

[Shipey]

Wheel hop under heavy acceleration is a known issue with the S550. Note the number of vendors offering improved vertical links, bushings and braces to stop the hop. A huge amount of et will be lost without traction. Also, without careful parts selection, you’ll get unwanted NVH. As far as magazine testing goes, you could be looking at numbers laid down by a professional driver on non-stock tires and the car could be a ringer. That was quite common in the 60’s. Yes, I’m that young!

And...a ‘68 Mustang GT with a 390 wheel hops like a mutha and those old Traction Lok (joke) posi rears never hook. Your Bullitt will kill one on the strip and through the twisties. Drive and enjoy it.

 

[GreenS550]

I am really enjoying the opinons. That's what this makes this forum so fun.

No, boys, go to the strip and show your slips! Also, Just because the HP drops a bit at max redline does certainly not mean 2nd gear is in the power! You guys are missing this. The reason the a10 is so fast is that it keeps the RPMs near their peak constantly. When we shift the Bullitt to second, the rpms drop significantly so getting more MPH is critically to keeping the next gear from having to build power.

I am convinced that launch control is not the best way to launch the car. Go to a vacant road and do a 0-60 MPH and see what it does. Damn hard to break 5 seconds.

My '15 with a tune only did it in 4.3. But, as has been said already this is not a 1/4 mile car.

The whipple is in the garage. Garage clean. Parts inventoried. I will post some phots on a different thread.

 

[cib24]

It's your 60 foot that is killing your times. It looks like you were averaging a 2.2-2.5 second 60 foot which is pretty terrible, even for a front wheel drive car. So, all it means is that you need to work on the launch and figure out how to slip the clutch slower to get traction sooner rather than just spin the tyres off the line.

With some more practice and perhaps a Steeda Stop the Hop kit you will get better and down to the 1.8 60 foot range you should ideally be cutting on street tyres in good conditions. When you get there your car is a mid-12 without much trouble.

Drag racing is a good dopamine hit regardless of the times you run as you try not to red light and beat your opponent to the 1/4 mile line.

 

[GreenS550]

Absolutely horrendous 60-foot time no question about that. I've never running into this on any other car stick or on automatic. What's really interesting is the track was prepped really good. so when you try to start letting the clutch out slow that stickiness just grab that axle and started banging it up and down. In trying to launch it without that your RPMs are too low and so the car has to build power with that long gearing or spin the tires with too much. It was quite a challenge. The BMR CBO 05 and Steeda location inserts are the first mods as I know they don't cause nvh.

 

[cib24]

Yeah, that totally makes sense. Sounds like you had really bad wheel hop. Be careful with that you could snap an axle or bust the diff. It's something I have to deal with in the RX-7 which makes it hard to launch.

 

[OldPhart]

I myself am sorry I bought this car -Yes its Beautiful But Man what a DUD this bullitt is --mine has 35 miles on it and i have no desire to drive it after i brought it home ,Its no comparison to my 18 A10 PP that car is Fast ... MY stock 2015 Scatpack went 7.9 in the 1/8 @ 94mph ,this Bullitt is not living up to the name !!! once i recieve the title its gone !!!

Hi - To paraphrase the recent Car and Driver comments: ... might be best all around Mustang ever - perfect balance of performance enhancements and desirable features with unmistakable appearance - an excellent daily driver... This is exactly what I expected and was actually surprised to see the included track features but I guess that’s because in its basic form it’s essentially a GT. I’m sorry you thought you were getting a great track car. I doubt that most buyers had that expectation. You should sell it to someone who will appreciate it for the modern high tech handsome Bullitt replica that it is. I’m very happy with it so far and hope to enjoy it for many more years since I’ve labeled it my (license plate) “LAST TOY”... Bruce

Sponsored