June 20, 2007This is the second time Iv taken my truck down the quarter mile The first time a ran a low 17 second pass, I wane a couple of weeks ago and ran basically the same possibly slower (cant find slips from last time..) First time I went truck was bone stock 4.6L sept for si/do exhuast and K&N drop in filter...Second time I had K&N cold air kit, programmer si/do exhuast and 20" wheels with 275/45 tires no spinning just a little chirp when I took off...Do you think it should of improved at all or do I have high hopes...I dont think the 20's should of affected it to much and I wasnt running the programmer on the 93 octane setting...Ran a 17.3@80mph (I have efans just need to install them think it will help??) Is this where I should be or should I be a little faster...(Im being realistic when I say faster I mean like instead of 17.3 like a 17.0 or 16.9)
Forums : Performance General : 1/4 mile time seems slow? (132 Views)
June 20, 2007I would think that the extra added weight from the 20's slowed you down some.
June 20, 2007
Could also be that the time before the temperature was cooler giving your motor cooler air. Was there anything different in the weight of the truck. Full tank of gas compared to empty? What was the temperature of the motor and other fluids?
June 20, 2007A lot of rolling mass to get going with 20's. Would definately slow you down a bit!!!!!
June 20, 2007If I remember correctly my 1998 F150 4.6L ran a 17.1 totally stock with just Flowmaster exhaust. Yours is about right.
June 21, 2007The first summer I had mine she ran in the mid 16's at Atco, NJ. At that point all I had was a Gibson Si/So catback.
June 21, 2007It will be slower with a bigger rolling diameter and stock gears. You might want to change your gears or go back to the same rolling diameter and you might see better 1/4 mile times.
June 21, 2007If you want to go fast on the strip, don't drive a 5500 lb truck with an anemic engine. 17 sec +/- 1 sec is about normal for a truck that size, and pretty respectable IMHO, given the fact that stock Lightnings run 13s.
June 21, 2007Switch to 3:73s, put on the efans, underdrives?(matter of opinion) get rid of as much weight as you can.
I have looked at a bunch of stuff on the 4.6 and the one thing that keeps coming up is the A/F ratio. Adding the intake and exhaust made performance drop because the motor would run leaner. They say 2% more fuel with those mods brings it all together. The only tuner that I know of that you can add fuel with is the xcal and diablo. I'm sure there's more but thats just what pops to mind.
Next thing would be to look at your 60' times. That will give you a good inication for gearing and traction.
After thought..........make sure rev limiter and speed limiter are off and bring your trans press to about 20+ stock ( the stuff I have read says thats the magic number, I started at 10+ and worked my way up to see how I liked it)
June 21, 2007I was thinking about gears some people told me I shouldnt need gears...I have 3.55 would 3.73 really help?? The first time I went a had a passenger with half tank of gas this time I had about 3/4 full and no passenger... The tire size is acctually a little smaller its like 29.7" or 29.5" vs 30.0" according to falkens specs...60' time is 2.506....Best R/T was .242 not bad for my fourth time down the track in my life... I think second gear is part of it, its pretty lame especaly when it gets into the top end of second first has some grunt feels good coming off the line then falls flat on its face in second and it gets into third about a truck length and half befor the finish line...So you think put programmer on 93 setting and let it rev out some gears more and my fans will help me out hit a 16...what about headers...There was a guy with a silverado ext.cab and he had everything I had (no efans and 5.3L) but he had JBA headers and hi-flow cats and his best time that night was a 15.1 he said stock it ran 16.5.... but the was an s10 with a 350 in it and it only ran 15.5...
June 21, 2007Long story short.............everything you do will help as long as you know what your adding.............i.e more intake more exhaust means a need for more fuel, stock will only take you so far before you need to work the tuner or get into more technical junk.
The gears are a given, 3:55s bog you down pretty hard. Big Mike from the Wa chapter put it best...........it's like driving with OD off. that just means instead of cruising 60mph at 17-1800 rpm, you will be around 21-2300.
Less work on the tranny for sure and more out of the hole.