Well, I won't be able to put my truck on a dyno for another two weeks, so I'm trying to troubleshoot some areas of my truck...

My best ET has been a 14.6, but worse then that has been the 95 to 92mph trap speeds. It's in Hawaii, so elevation is no factor, even though heat/humidity is.

What on earth could be wrong? Also, I don't think my fuel filter has ever been changed - I know I haven't changed it, and I've had it for 10,000 miles, and the truck has 35,000 miles on it... I doubt something as simple as a filter could be the cause of a huge mph trap speed problem, but I've heard they do need to be changed out. Is this easy to do myself, and where do I buy the parts?

Any other help or input is appreciated. Thanks so much.

 

First things I would check/verify:

What kind of boost level are you hitting?
Unplug your boost bypass solenoid unplugged or do the bypass mod (you may be dumping boost).
Change fuel filter.
Check spark plugs.

If none of the above help, it's time to talk to a tuner.

 

sounds like boost bypass problem to me. That et seems to be in line with your mph. Can you post your 60ft time.......330 and 1/8 mile times from the timeslip?? That would give plenty of info.

 

Thanks for the help. This is from my best ( ) run.

60' ... 2.245
1/8ET 9.441
1/8MPH 76.39
1/4ET 14.624
MPH 95.09

As far as boost, the stock - crappy - guage is reading around 9-10psi, sometimes a little lower. I've had a hard time watching it, since I'm new to drag-racing and trying to watch everything at once. So that's really a rough estimate.

I'll check the plugs - I'm ordering some TR6s and they should be here soon anyway, do the boost bypass mod this weekend, change the fuel filter this weekend, if I can figure out the part number and hopefully NAPA down the street sells the right part...

If that doesn't fix it, I don't know. I just know that everyone has said when all is said and done, crappy run and all, a 100mph trap should be normal, and 5-8mph below that most definitely is not. And since I can't go to the dyno for at least two weeks... Just trying to troubleshoot on my own.

 

I would definetely say it's a boost issue........probably the bypass.

Your 60' time isn't great, but not uncommon for novice racers......especially with these trucks (i know cause i can't drive worth a damn )..........76mph in the 1/8 seems really pokey, even heat and if it's a stock truck it should be a little faster than that. My stock 2000 ran 80mph at the 1/8 mile marker..........that was on a 14.2 run.

Are you running wide open throttle. Possibly your not putting it to the floor.......or your throttle body not opening all the way. Just some thoughts.

 

You know, I was so concerned about not pushing the throttle down all the way, that I actually made a point once of "standing" in the seat, just to make sure. Sounds kinda stupid, but I am a newbie racer, and I just wanted to make damn sure. So I know for a fact I'm running WOT.

How much does a fuel filter cost, by the way? Is it an easy driveway job?

Hadn't thought about the throttle body... How do I check that?

Thanks again, this is alot of help and good input.

 

Id check the boost bypass i had a similar problem it was working out according to the folks at ford it was ok. But once i replaced it boom problem solved. i went from running high 14s to mid 12s by replacing that part no other change

 

Sounds good. I've never messed with that, or done the mod... I'll check it out tomorrow after doing a search (looks around for Tim) to see exactly what I'm looking for and what I'm doing. The previous owner might have done something, or it could just be working loose, or something....

Thanks alot, everyone. I appreciate it.

 

Your OE fuel filter number is FG-986B

But if you want a larger capacity one? Go for a FG-872 (it's off of a 5.4L 4v navigator) Only thing on the bigger one is that you need to somewhat bend the bracket and add a large enough clamp to hold it on. (I've done it twice now with no problems)

Oh and the FF is in the frame rail, on the drvr side, at about the back of the cab. If you can slither under the truck you could easily do it on your back. Mines lowered a bit so I gotta lift mine a few inches.

Rich

 

Change your fuel filter! I had about 8,000 miles on my truck and was STUCK at 13.0X's for weeks. Had a 4lb lower, chip and torque converter. Was suggested to change my fuel filter by Jim and Shawn at JDM....... 12.52 the next time out with NO other changes. Filter was clogged, I could just barely blow thru it. Change the filter, it is cheap and even if it doesn't help you, atleast you have a new one, especially if yours is still original. -Mat-

 

Duende,

Does your truck have the Indash 6 CD changer radio?

 

 

Thanks for all the great info, everyone. I'm going to go pick up the filter tomorrow and change it out, and check/do everything else people on here have suggested...and then hit the track tomorrow night. If I run under a 14.6, I owe everyone who posted in respose a few beers if I ever meet any of ya.

I don't have an indash 6-disk, unfortunately. Wish I did.

Again, thanks!

 

Mat said it best

CHANGE YOUR FILTER, nothing to lose AND ALL TO GAIN

BTW
I was stuck in the 13's when my truck was DAM NEAR BRAND NEW,
I also kept complaining about no power up top, seemed like it was cutting in and out, we tried more gas, diff, gas, diff tune, etc...
The problem started when the truck had about 3K on it, so we never thought of the Fuel Filter. Well by the time it hit
5000 miles I found the problem


My next run got me my 1st 12's and I've never looked back
(but I do change it every 3K now)

Oh Ya, BTW it almost cost me a Motor,
TG I got away cheap..

Plugs were brand new at the time, a few weeks old,
believe me you DO NOT want to have to do that job over for schitts and giggles.

Change the Filter, it's waaaaaaaaaaaaay over due
Read this, it's a great "HOW TO" on changing the filter
https://www.f150online.com/forums/sh...threadid=71442

 

Whoa. Thanks for the pics. Pretty ugly.

Taking care of that first thing in the morning, soon as I wake up. Probably order some new spark plugs while I'm at it, since I'll need to anyway with my nitrous and 4lb on the way...

Thanks again.