I couldn't find many equivalent references in the archives here (https://www.f150online.com/forums/sh...install+pulley, https://www.f150online.com/forums/sh...lley+direction), but this thread over at NLOC is interesting:

http://www.nloc.net/forum/showthread...threadid=31269

Will someone please confirm or correct my simple conclusions?

1) No two L's are created equal, or driven in identical climates, conditions, etc. Thus, the best and safest way to tune your L is with the proper measuring equipment and tools that allow you to customize your mods/tune to your specific requirements.

2) Chips are beneficial for a number of reasons, but are not "necessary" when adding a reasonably sized pulley (2,3, 4 lbs lower pullies?).

3) It might be safer to run a 4 lb pulley without a chip than to run a 4 lb pulley in conjuncton with a chip (safer = less chance for detonation). However, the 4-lb pully by itself will not yield as much of an improvement, without the help of a chip to squeeze out the last drop of available performance.

Which leads me to another question that I have:

Exactly how fast is an unchipped L with a 4-lb pulley, vs a chipped one with the same pulley? Can we make any simple relationships (assuming similar "street" chip programs for all tuners, etc)? For instance:

Does a 4 lb pulley alone (stock computer) yield the same performance as a 3 lbs pulley + chip combo? Or is it more like the improvement seen with a 2 lbs pulley + chip?

Anyone have any data or insight?

 

Me personally, would not strap a 4 or 6# on the truck without a chip and a dynotune. Thats $33K wasted at that point. Some people have done it though. Theres a lot of variables that play into it. Quality of fuel and octane, weather, climate and altitude. Youre correct, no 2 trucks are the same. My truck is an absolute ****** when it comes to dyno tuning him. He doesnt like a lot of timing. My truck makes more hp with less timing and fuel, then it does with more.

 

I'll throw in my .02:

I was at the track this past summer with a 6lb pulley and chip. I accidently ran it with the chip in the stock position on one run. I was upset that I had done it, but I heard no detonation/pinging.

I ran a 13.4 @103 with the chip in the off position, went back to back for another run with the chip on my more aggressive side and ran a 12.8@107. Stock I was around 13.8-13.9 @ 100.

I won't run it again with the chip off, but I feel that the stock computer can handle the extra boost to a certain extent. Of course you won't get the full benefit of the boost without the proper tune.

 

Flying ****, so in your opinion, you disagree with the statement that a 4lb pulley is "safe" and feel that the milder 2 and 3 lbs pullies are the theoretical safe limits for the stock computer? Do you have empirical evidence to support your opinion (not flaming, just probing for any experiences you have to share). Do you feel this way because you think a 4lb pulley would max out the voltage reading on the MAF and force the computer to use a potentially dangerous map? (Would changing the intake filter, throttle body, or other intake mods fix this?)

EvilL, thanks for those data points. Those are exactly the kind of numbers I wanted to see. I am curious about one thing, when you said "back to back" runs, does the computer need to be reset or run for a certain amount of time to "relearn" or adjust to the new program? Or does it adapt all the time, and changing the program has immediate consequences?

 

For my chip to work it has to be flipped to either tune 1 or 2 before the car is started. Once the chip is on it can't be turned back to stock until it is turned off. Same if the chip was off and I wanted to go to one of the tunes, I would have to turn it off, flip it and turn it back on.

I only flip between the two tunes, but somehow I managed to turn it off while the truck was off in the staging lanes. I didn't realize it until I got to the end that I had left it off. I got back in line, shut the truck off, changed to my 2nd tune and started it back up and ran again. It wasn't a busy track so I only waited a few minutes before I got to run again.

I am not sure about the computer having to relearn or not. The only time it was on the stock tune was from when I started it up and ran until I got back to the staging lanes. I lost approximately .6 and 3 mph using the stock settings.

 

Sixpipes ran his truck with no chip at a recent race event.

I believe he ran in the 12's with no chip.
I believe he is running a 4# pulley..

BUT his is a 99 and He is the urban legend so normal mortals should NOT try this at home...

Doug

 

Im in CA. Everyone knows we have the WORST gas you can get. 91 octane and heavily oxygenated. I would not even take the chance of running a pulley greater then 2# without a chip for safety sake. If i had $10K to blow, perhaps i would attempt testing on pulley's with no chip using the stock computer. However im not that rich.

Now, after performing some data logging the other night, i honesly feel the stock computer cannot adjust WOT A/f in a safe manner for large pulley's. Look how easy programs change in cold weather. Its down right scary. The stock computer just isnt consistant enough to be trusted imho.

 

you know they do have adjustable fuel pressure regulators??? install one of those and a A/F meter with any pulley you want and then adjust the fuel manually?

 

BMW,

Looks like the basic fact of it is yes, you can strap on an unchipped 4lb pulley, BUT you are leaving yourself very little room for error in the quality of anything pertaining to the truck (weather, gas, a bad plug, etc).

It would then just go to the point, do you want to take the extra step, the time and the extra buck to have better odds that your truck won't blow up? Then dyno tune it to an A/F that you feel safe with.

Remember, without a chip or twEECer, you cannot control your own A/F.

Daniel

 

Same day event in Hallsville, TX.

4# pulley w/o chip 12.95 (best ET)
4# w/JDM street chip 12.38 (best ET)

I would not suggest running a lot of mods without a chip, especially the 01/02 model years.

 

Hey Killa,
When you get a chip tuned is that how they control the fuel pressure in our trucks? Is this why I haven't seen anyone mention an adjustable fuel pressure regulator?

 

Its going to take more then an adjust FP regulator to control your a/f

However, you can control parts of your a/f with a Mafterburner.

 

Very interesting info and Post. It seems to me we just had two great examples of how a chip can give you 6/10's more than NO CHIP. Schitt, we even got to hear that from the urban legend himself, whassup six Pipes

I have read many post on this topic BMWBig6,
What I always say and how I feel is this, Ya you can do it, BUT WHY WOULD YOU WANT TO ???? Why ignore the biggest and best Mod we have available to us, Dam near 50 HP and Torque, not to mention 1/2 a second for a couple or few hundred bucks. Quite frankly I don't see how the hell anyone can drive a Lightning with the factory fuel cutoff, rev limiter, torque reduction, mushy shifts, and lack of timing.

Bottom line, if you want to run 4-6 lbs of pulley, BE SAFE.
Run a A/F in the low to mid 11's, maybe kiss 12 for a track program. Use 15 degrees of timing on the street, and 17 degrees with your race program. Last and most important, run ""2"" ranges colder on your plugs (use denso's and your pretty much grrnty a good idle and no misses) To me, this is safe, never ever any detonation, and it'll get you enough power to hit your goals.

 

FYI, Just to confirm. I ran all last year at the track and street with 3# lower, TR-6 plugs and no chip. All 7k miles worth. It droped my ET .3 in the 1/4. Checked the A/F. No problem.

I would not run 4#-6# without a chip. I'm also running the 3# in current temps here in Michigan, single digits and no detonation.
Runs great.

 

ET's are driver-dependant. Trap speed is a much more reliable measure of power gains.