[R0B0T]

for the first time.
and it seems like something is wrong.
either my car is geared too low (4.30's) or i have valve float or something thats choking me out on top end.
the car seems to pull good at first, but the farther i get down the track the weaker it pulls.
im crossing the traps at the very top of 4th, i can shift into 5th instead of revving out 4th and still get the same ET.
the car seems to stop pulling hard at around 4500.
my buddies in the stands tell me it pulls hard the first half of the track, but after that it looks like its not pulling at all.

1/8 mile mph: 72.42
1/4 mile mph: 88.77

i cant launch hard (1800 rpm) with these tires i have now, but that still shouldnt be causing me to get 15.5 second passes in this car.
granted, i might spin a little bit, but i still wouldn't be convinced everything was ok with a 14 something. granted, i do have time available in my suspension, i had air in the air bags the first pass and ran a 15.2 with tires at 40 psi, then i let air out of my air bags and tires and ran worse every time.

im just curious wtf is going wrong here.
and i know im not going to be pulling awesome numbers my first time out, but i think something is wrong besides me.

car is stick shift, bolt ons, mild cam, 4.30's, and fat tires.

[e3sean]

4.30's are killin ya with no tires. if u have to shift into 5th in the quarter then u need a 4.10 or 3.73 what bolt ons do u have?

[ujslost]

4.30s are steep as hell on a fox body. Get some 3.73s or .3.90s thats what i have.

[ryans88gt]

based on your MPH, you car is lacking the power to run much faster than 15s.

[R0B0T]

keep in mind that im spinning 1st and 2nd

[ryans88gt]

that will make your MPH higher if anything. 88 mph means you are down on power regardless of gearing or how well you launch.

[R0B0T]

Originally Posted by e3sean 4.30's are killin ya with no tires. if u have to shift into 5th in the quarter then u need a 4.10 or 3.73 what bolt ons do u have?

long tube headers, mass air conversion (i think, theres 4 wires going to the air sensor thing, and nobody gives me an answer as to whether or not thats mass air), smog delete, lower control arms, air bags in the coil springs, and thats all i can think of.

[ryans88gt]

If you have a mass air meter, then you have mass air. Speed density cars had no sensor in the intake pipe.

[R0B0T]

Originally Posted by ryans88gt that will make your MPH higher if anything. 88 mph means you are down on power regardless of gearing or how well you launch.

ok thanks.
also when i rev my car up to like 5k when in neutral, when it is dropping in revs it "hiccups". dont know what thats about.

i was wondering if i could have melted my cats and they are clogging my exhaust since the previous owner took off the smog pump.

[ryans88gt]

Sounds like you have some issue, could be the cats, could be the EFI. You can always take the H-pipe off and take it for a drive...

[R0B0T]

yeah thats gonna be what i end up doing this afternoon.
ill update after the drive.
thanks.

[Iwannagofast]

yeah those speeds are way low......i crossed the line at 86 mph in the 1000 ft and my car is pretty stock.....even stock gears

[ryans88gt]

You have O2 sensors in the long tubes right? Why do you have long tubes and cats anyway?

[R0B0T]

Originally Posted by ryans88gt You have O2 sensors in the long tubes right? Why do you have long tubes and cats anyway?

yeah the O2 sensors are at the end of the long tubes, and i bought the car that way a little less than a month ago. i too, was surprised that they put cats on. they had to chop the exhaust up and re weld it just to get them on there.

[R0B0T]

i just took it down the highway with open headers and there's no difference in performance that i can notice. i looked at my exhaust and they hollowed out the cats to fool whoever would look i guess.

im wondering if my MAF sensor could be dirty?
is it a q tip and rubbing alcohol you clean it with?

[nolife]

Originally Posted by R0B0T im wondering if my MAF sensor could be dirty? is it a q tip and rubbing alcohol you clean it with?

That's what I've always done. They sell cans of stuff for cleaning the MAS as well, should be on the chemicals shelf near the throttle body cleaner. I never used it though and it is probably no better than the qtip.

[R0B0T]

cleaned the MAF sensor, i think that fixed it.
1st through 3rd lost 1000 rpms and that was only from 2nd into 3rd.
1st to second tach never fell below 5G's.

i will update after hitting the track next wednesday.

[R0B0T]

no need to wait that long.

after 30 minutes of driving, car started bogging down again.
unhooked the MAF sensor and aside from a crappy idle, she ran like a beaut.
would it be safe to get the sensor from a junkyard?
or should i order it new?

[ryans88gt]

are you running an air filter? An oiled air filter? With maybe too much oil on it?

[Darrell]

Originally Posted by R0B0T for the first time. and it seems like something is wrong. either my car is geared too low (4.30's) or i have valve float or something thats choking me out on top end. the car seems to pull good at first, but the farther i get down the track the weaker it pulls. im crossing the traps at the very top of 4th, i can shift into 5th instead of revving out 4th and still get the same ET. the car seems to stop pulling hard at around 4500. my buddies in the stands tell me it pulls hard the first half of the track, but after that it looks like its not pulling at all. 1/8 mile mph: 72.42 1/4 mile mph: 88.77 i cant launch hard (1800 rpm) with these tires i have now, but that still shouldnt be causing me to get 15.5 second passes in this car. granted, i might spin a little bit, but i still wouldn't be convinced everything was ok with a 14 something. granted, i do have time available in my suspension, i had air in the air bags the first pass and ran a 15.2 with tires at 40 psi, then i let air out of my air bags and tires and ran worse every time. im just curious wtf is going wrong here. and i know im not going to be pulling awesome numbers my first time out, but i think something is wrong besides me. car is stick shift, bolt ons, mild cam, 4.30's, and fat tires.

Did you replace the valve springs when you put the mild cam in? The 4.30 gears will be fine for that car but it sounds like you are running out of power way too early in the rpm range. Just for comparison purposes I've consistently run in the high 90 mph range with bone stock and bolt on only Mustangs.