Cant hit 13's!!!

[stanger9219]

Went to the track last night, the weather was really good. My first, and best, run was a 14.29. I barely spun at the start a nd powershifted and thats the best I could do. There was another run where I missed fourth gear and still ran a 14.33, I think I coulda hit a 13 there but I screwed it up. Its probably all in my driving but its kind of aggervating that with my mods I cant hit 13's easily.

[Dark_5.0]

What was your mph and your 60ft?

[xxxBlakexxx]

Yeah, fill us in. I don't know much about a '98 Cobra, and what it should run, but obviously you think it should hit 13's. If you are gonna miss a gear, 4th is the one to miss as you are already going fast at that time.

Did you correct your times for altitude and weather? That can tell you alot.

You may need to spin a bit more actually...not too much. Also, drop some air in your rear tires....20 lbs. This will allow you to launch at a higher rpm.

[stanger9219]

for the 14.2 i had a crappy 60ft. of 2.265. My mph was 99.55 on that run. When I missed fourth i had a 2.1 60ft and a mph of 96.73, haha.

[xxxBlakexxx]

Generally speaking, if you spin too much at launch, your 60 foot will increase and so will your trap speed. If you bog too much, your 60 foot will also increase, but your trap speed will decrease.

Missing fourth I am sure cost you a bit, depending on how bad it was. Let's assume, had you hit the gear properly, you might have taken .2 off and added 2 mph to your trap and your just about in the 13's.

If you can pull 2.0's flat on your 60 foot, you will get into the 13's. For each .1 drop in your 60', you will see a .2 decrease in your 1/4 mile. Practise launching (me too) and you should get there.

Also, what altitude is the track? I have messed around with compensation programs, and it seems that for each 1,000 feet in elevation from sea level, will cost you .4 - .5 seconds in the quarter. My track here is at 970 feet, so a 14.0 is like getting a 13.5 - 13.6 in Florida. You need to keep this in mind when comparing your times to others around the country. Of course, is your comparing yourself to others at your track, you will all havethe same handicap.

Weather is a big factor too. If you ran at 90 degrees and 95% humidity and then run again at 70 degrees 75% humidy, you should run .2 - .3 faster. Hot weather tends to made street tires slip also.

If you do not know how to compensate, give me all the data off your slip, including track altitude, temp and barametric pressure when you ran (should be on the ticket) and I can do it for you.

[Dark_5.0]

Originally posted by stanger9219
for the 14.2 i had a crappy 60ft. of 2.265. My mph was 99.55 on that run. When I missed fourth i had a 2.1 60ft and a mph of 96.73, haha.

Get 2 spare rims and some slicks. Dump the clutch about 4000 and you will run about a 13.7 @100mph.

Drag racing on street tires is a waste of time and money. I used to pull 2.0 60 fts on street tires and thought I was doing so good. Then I bolted on some slicks and cut 7 tenths off of my ET.

Right now traction 0wns you

[explicitone]

where are you shifting(what rpm)

[blue00gt]

A guy at Infineon last time I was there had the same car as you. Only mods were 3.73s and Nitto DRs. He was running 13.7s at a little over 100mph with a not-so-great 2.0 60-ft.
Like they said - if you want good ETs it's all about the launch. If you can't make traction more hp will just make it tougher.

[Dark_5.0]

"If you can't make traction more hp will just make it tougher."

Everyone read and understand this amazingly accurate quote.

[fiveOguy20]

ok, i've posted on this subject like 3 times, lol U NEED TO HAVE THE COMPUTER RETUNED OR A CUSTOM CHIP BURNT FOR THE 4.10s; hahaha.. i said that in all my posts. according to every speed shop i've been to that knows there SN cobras say that it will run like dog s*** until u retrain the computer.. do this an i promise ull be 100% happier , o an if i u dont believe me still, look at the user ride section on this site, an look at all the 96-98 cobras that are goin 13's an faster. that should give u an idear . also my 96 cobra actually ran slower when i put 4.30's in until i chiped it.. WORLD A DIFFERNCE

[Dark_5.0]

Originally posted by fiveOguy20
ok, i've posted on this subject like 3 times, lol U NEED TO HAVE THE COMPUTER RETUNED OR A CUSTOM CHIP BURNT FOR THE 4.10s; hahaha.. i said that in all my posts. according to every speed shop i've been to that knows there SN cobras say that it will run like dog s*** until u retrain the computer.. do this an i promise ull be 100% happier , o an if i u dont believe me still, look at the user ride section on this site, an look at all the 96-98 cobras that are goin 13's an faster. that should give u an idear . also my 96 cobra actually ran slower when i put 4.30's in until i chiped it.. WORLD A DIFFERNCE

Why would you have to have your ecu retuned for gears???????????????????????????????????

Rear end gears have nothing to do with the engine. It doesnt know the difference.

I know several people running 12's with untouched ecu's and gears.

[explicitone]

Originally posted by fiveOguy20
ok, i've posted on this subject like 3 times, lol U NEED TO HAVE THE COMPUTER RETUNED OR A CUSTOM CHIP BURNT FOR THE 4.10s; hahaha.. i said that in all my posts. according to every speed shop i've been to that knows there SN cobras say that it will run like dog s*** until u retrain the computer.. do this an i promise ull be 100% happier , o an if i u dont believe me still, look at the user ride section on this site, an look at all the 96-98 cobras that are goin 13's an faster. that should give u an idear . also my 96 cobra actually ran slower when i put 4.30's in until i chiped it.. WORLD A DIFFERNCE

the only time the computer needs to be tuned for gears is if the car as a auto and to fix the speedo thats it

[fiveOguy20]

not so.. i'm goin by what pauls highperformance told me not by my own opions. they said that on the cobras of those yrs puttin in a bigger gear throws off the ignition an fuel curve causing it to not perfrom like it should. again i have a 96 cobra myself an i had the same issues until i had a chip burnt. i went from low 14's to low 13's.

[xxxBlakexxx]

I will buy that only if you can explain it.

Gears have nothing to do with the engine, a/f, or whatever. UNLESS, on that car, the timing advance depends on mph inputs which I seriously doubt. Gears w/o a calibration, of course throw the speedo off which is easily fixed.

[blownbyyou]

I found out that you will run slow if you have a full tank of gas. for ever gallon of gas you add on 5lbs or around there. take out the back seat and spare tire too.

[explicitone]

Originally posted by blownbyyou
I found out that you will run slow if you have a full tank of gas. for ever gallon of gas you add on 5lbs or around there. take out the back seat and spare tire too.

im not sure but I think a gal of fuel is 7.8lbs

[Luka]

There is no need to chip a cobra for a rear-end gear change.
Ive been a ford tech for 8 years, i own a 97 cobra myself...

Mods:
4.10s
off-road h-pipe
underdrive pullies
BBK throttle body
pro 5.0 short throw
2 chamber flowmasters/dumped
MAC cold air intake
(may be forgetting something)

Going from memory on times here
1/4 13.5xx
mph 106 or so
street tires

Never once touched the PCM other thn ford issued calibrations. A rear-end gear change will NOT affect an any way the way your engine will run in these cars....fact, thats the way it is.

Ofcoarse if you put a more agresive tune on it it will run faster but it has nothing to do with what gear you are running.

Its tricky to get a good launch on these cars....a fine line between roasting them an boggin it cause you really gotta wind em up to get some times out of em.

Most serious cobra n/a racers run slicks, beef the drivetrain a bit (axles/rear-end girdle ect) an drop it off the line at a good 6-7k rpm launch an turn in some amazeing numbers. These cars dont generate the best tourqe in N/A form so ya gotta get the rpms up there where the car makes its HP....

Work on your Launches...the power is there for sure.....97s stock ran a 14.0 you have a solid 13 in that car for sure! keep practiceing....

Luka

[TARZAN]

Drag Radials

-Will

[Luka]

Tarzan knows how to get there too!

Drag radials would make a huge differance for sure.

Luka