Automatic 1/4 mile

[Gotz]

On many Mustang forums I notice a lot of automatic owners wondering what they'll average in the 1/4 mile, basically stock. Welp, I finally got to run mine 3 weekends ago and figured I'd throw some input into the numbers I got.

It's a 1998 Mustang GT, non convertible. 75,000 miles. Has 17's on it with 245-45-17 tires (factory size).

Only modification is a X-pipe. Stock manifold, stock mufflers. Stock intake. Was also at stock height, whereas it isn't as of 2 weeks ago. (Hope to run it again lowered, not that it'll really matter).

Car is also at factory weight. Also have a 30lbs sub box in the trunk along with a 30lbs toolbox. 60lbs? Not an issue. 165lbs driver.

I know the type of tires might matter but they hooked right away. No spinning at all, so I doubt that's an issue either. Heated them up pretty decent before approaching the start line.

Now realize, this is a 98 GT. 96-97 had a 10hp decrease and a 5ft.lbs decrease.

It was about 55 degrees out and I had a half tank of gas.

I ended up running a 15.006 (.477 reaction). Made 4 passes and they were all VERY close. The slowest was a 15.024 (.524 reaction) This is much better then I expected because most of the forums I've read, they say mid to high 15's.

A big issue I'm noticing on this car (probably all 96-98 GT's NPI) is the fact that it runs out of breath before the shift point. So for about 400-500rpms, you can feel it lagging until it hits the next gear. Especially 2nd to 3rd. Right when I hit 3rd, I'm at the finish. Maybe once I gather up a PI intake and PI cams.. it may breathe a little better. Was thinking about purchasing a programmer for the "shift points" but I'm pretty sure that's the daily driving shift points. Not the redline, although I may be wrong. If I am, please let me know. I'd hate to get into serious tuning just to change my WOT shift point from 5800 or so to 5400 or so. Once 2nd switches to 3rd, there's a HUGE power gain once it's back into it's powerband. I'd be in high 14's if it wasn't for the high rpm lag between gears. :undecided:

 

[RichV]

You'd prolly hit high 14s if you took the 'junk out of the trunk', lol. Seriously, they let you run with that stuff??

Did you stage off the converter? Your MPH and 60' will tell you what the car is capable of. Reaction time does not matter, not in the 1/4 mile ET, any 60' improvement will pretty much subtract from the finat ET.

Pretty nice work. My 86 AOD GT was very consistent at 16.25 sec. That was with a couple of boltons, but at 5800 ft.

 

[Musturd]

Wtf they Let you run with tool box's in the trunk please get that crap outta there. Yea the 2v's like to be shifted around 5400-56 that's how my NPI shit box liked it enough to do 13's on et streets of course

 

[MaxxRPM]

You'll definately like the PI intake then. Mines an auto and with the PI intake (along with CAI and a cat back) it pulls hard all the way up to the auto shift points (5500). Sometimes I shift it out manually at 6K.

 

[Musturd]

If you read his posts at wot his car is shifting at 5800 these things fall on there face by then

 

[MaxxRPM]

Right, but the point I was making is adding the PI intake improves power in the upper Rs.
Now, with that being said, I can't say I recommend doing so (mine leaks).

 

[justinschmidt1]

On many Mustang forums I notice a lot of automatic owners wondering what they'll average in the 1/4 mile, basically stock. Welp, I finally got to run mine 3 weekends ago and figured I'd throw some input into the numbers I got.

It's a 1998 Mustang GT, non convertible. 75,000 miles. Has 17's on it with 245-45-17 tires (factory size).

Only modification is a X-pipe. Stock manifold, stock mufflers. Stock intake. Was also at stock height, whereas it isn't as of 2 weeks ago. (Hope to run it again lowered, not that it'll really matter).


Car is also at factory weight. Also have a 30lbs sub box in the trunk along with a 30lbs toolbox. 60lbs? Not an issue. 165lbs driver.

I know the type of tires might matter but they hooked right away. No spinning at all, so I doubt that's an issue either. Heated them up pretty decent before approaching the start line.

Now realize, this is a 98 GT. 96-97 had a 10hp decrease and a 5ft.lbs decrease.

It was about 55 degrees out and I had a half tank of gas.

I ended up running a 15.006 (.477 reaction). Made 4 passes and they were all VERY close. The slowest was a 15.024 (.524 reaction) This is much better then I expected because most of the forums I've read, they say mid to high 15's.

A big issue I'm noticing on this car (probably all 96-98 GT's NPI) is the fact that it runs out of breath before the shift point. So for about 400-500rpms, you can feel it lagging until it hits the next gear. Especially 2nd to 3rd. Right when I hit 3rd, I'm at the finish. Maybe once I gather up a PI intake and PI cams.. it may breathe a little better. Was thinking about purchasing a programmer for the "shift points" but I'm pretty sure that's the daily driving shift points. Not the redline, although I may be wrong. If I am, please let me know. I'd hate to get into serious tuning just to change my WOT shift point from 5800 or so to 5400 or so. Once 2nd switches to 3rd, there's a HUGE power gain once it's back into it's powerband. I'd be in high 14's if it wasn't for the high rpm lag between gears. :undecided:

My 96 Auto with 3.73s ran 14.5@96 mph back in the day

You would be better off putting a PI intake on it to let it breath up top rather than trying to drop the shift points...Pi cams as well would help.

 

[Gotz]

Yes, they never checked the trunk of the car. Checked everything else though. I wouldn't have taken my toolbox if my buddy wasn't having an issue. We noticed anti-freeze had sprayed a little under the bay but he wasn't sure if it was his fault (working on it the previous night) or if it was the system leaking. So it was for his caution. It's all strapped in, so I didn't think it would be a big issue. I do plan to take the sub and toolbox out next time I run.

As for RichV, I'll post more info on the 15.006 run, 60ft time and such. And I didn't brake boost or anything. Held the brake with my left foot, let go hit the gas on green. My 4th run (lowest time), was when I ran the 15.024 was when I actually brake boosted. Even though I did, I still didn't spin. Thought I would get a better time. I also let her cool down for an hour before the 4th run. After 3 back to back runs, I knew she was in for a break.

And MaxxRpm, that it the only thing holding me back. The original owner had the infamous leak fixed and had the entire intake manifold replaced with the upgraded one so no more leaks. Seems like the PI intake install is a hit or miss. Some people have leaks, some don't. I'd hate to swap a perfectly good intake manifold over with something that's gonna leak. We'll see.

 

[justinschmidt1]

It won't leak if you do it right it's pretty simple you use a pI gasket and a dab of silicone in the corners of the water jacket port

 

[MaxxRPM]

It won't leak if you do it right it's pretty simple you use a pI gasket and a dab of silicone in the corners of the water jacket port

Yup.............Unless it's my car. After setting it twice (simple as it is), the third time will be on top of PI heads.........:wave:

 

[justinschmidt1]

Yup.............Unless it's my car. After setting it twice (simple as it is), the third time will be on top of PI heads.........:wave:

weird lol

are you sure you were doing it right?

A million people have done it without issue

 

[MaxxRPM]

Believe me, I wish it didn't leak. I thought about going back to the NPI intake (even bought one at a junkyard), but love too much the way it runs now. When I hear about other peoples NPIs falling on their face in the upper Rs, mine screams all the way to redline (or very close to it).
If it didn't leak, I wouldn't even be doing a PI swap...........:nono:

 

[justinschmidt1]

Believe me, I wish it didn't leak. I thought about going back to the NPI intake (even bought one at a junkyard), but love too much the way it runs now. When I hear about other peoples NPIs falling on their face in the upper Rs, mine screams all the way to redline (or very close to it).
If it didn't leak, I wouldn't even be doing a PI swap...........:nono:

hmm idk man,

all you do is put a PI gasket down and a nice big dap of silicon here:

and it should work out fine, youve gotta let the silicone set and dry overnight atleast.

You went and got new PI gaskets? And its leaking from right there where the manifold meets the head?

 

[MaxxRPM]

Hard for some to believe as I'm aware but..........I'm 47 years old and been doing this stuff all my life so this by far isn't my first rodeo...........:grin:
It's hard for me to even image that I can't set this intake without leaking but others can..........:angry7:
.........That's why I have to chalk it up as some leak, some don't............As the OP even noted himself.

Btw, I've done all the reseach (looked at that pic atleast a dozen times)..........and it's definately not hard to do.............The second time, I let it set a couple days...........dry.

 

[justinschmidt1]

lol ok no disrespect..im just saying, things happen for a reason so if its leaking from that water jacket port its obviously not sealing off properly for w/e reason.

 

[Gotz]

60" 2.151
330 - 6.266
1/8 - 9.648
Mph - 73.38
1000 - 12.544
1/4 - 15.006
Mph - 92.48

 

[MaxxRPM]

What gears you Gotz?.........lol!

 

[gate keeper]

I remember my first time going to the track was in a 96 bone stock automatic GT with nothing pulled out of it.

15.4 @ 88

RACECAR

 

[justinschmidt1]

I remember my first time going to the track was in a 96 bone stock automatic GT with nothing pulled out of it.

15.4 @ 88

RACECAR

Was it a vert at high altitude? Jesus that seems slow haha.

 

[Gotz]

I'm pushing towards the gears being 3.08's. The 96' and up have the 4R70W transmission. Every time I get under the car (which is all the time), I always forget to check my rear end for the ratio numbers. Everyone says these sn95's have the 2.73's in the automatics but after reviewing a chart, having 2.73's would SUCK. Based on the chart, 70mph will set me at 1700rpms with 2.73's and a tiny tad over 2,000 with 3.08's. I'm at 2,000 at 70mph. And I would be pretty pissed if my first gear ran all the way out to 55mph. (2.73's).

Here's the chart. http://www.paladinmicro.com/pmicro.php#

Also, I don't think my elevation's very high. I go to Capitol Raceway. It says 300ft.