stock lightning lower crank pulley or supercharger pulley

throttle jockey

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First off, before modding replace all fluids for piece of mind. Also, change the in-line fuel filter. This should be done every 2-3 oil changes. Its cheap and easy insurance.

Do not swap the upper pulley. In order to increase boost by swapping the upper pulley a smaller diameter pulley must be used which increases the likelihood of belt slip. The same can be achieved with a larger crank pulley.

4# or 6# lower pulleys are the norm. If reliability is of concern stick with a 4# lower. 6# pulleys are generally "safe" but they are more aggressive.

You'll need to swap plugs and retune for either a 4# or 6# pulley. You will also want to consider upgrading the MAF, especially since your truck is a '99 which came with a 80mm MAF from the factory. Use of a MAF extender such as the DiabloSport MAFia or an entirely new MAF such as the SCT BA2400 or BA2600 will ensure you don't "peg" the OEM MAF. "Pegging" the MAF results in blown motors and is possible with the use of 4# or 6# pulleys, particularly in the cool/cold winter months.

NGK TR-6 are great spark plugs which are inexpensive. The TR-6's will be in the desired heat range for either a 4# or 6# lower. Gap them to .034"-0.36".

Check to see if the intercooler recall has been performed on your truck. The '99-'00s where prone to leaking intercoolers. You might also want to clean your intercooler for piece of mind. Check out the "How-To" section for a thread to walk you through it step-by-step.

Invest in gauges also, vital but overlooked mods. I suggest a wideband air/fuel gauge, fuel pressure gauge and a vacuum/boost gauge. I'm also a big fan of the AeroForce Interceptor scan gauge due to its versatility.

Welcome to the addiction :thumbsup:
 

SVT BLACKOUT

THE BATRUCK
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First off, before modding replace all fluids for piece of mind. Also, change the in-line fuel filter. This should be done every 2-3 oil changes. Its cheap and easy insurance.

Do not swap the upper pulley. In order to increase boost by swapping the upper pulley a smaller diameter pulley must be used which increases the likelihood of belt slip. The same can be achieved with a larger crank pulley.

4# or 6# lower pulleys are the norm. If reliability is of concern stick with a 4# lower. 6# pulleys are generally "safe" but they are more aggressive.

You'll need to swap plugs and retune for either a 4# or 6# pulley. You will also want to consider upgrading the MAF, especially since your truck is a '99 which came with a 80mm MAF from the factory. Use of a MAF extender such as the DiabloSport MAFia or an entirely new MAF such as the SCT BA2400 or BA2600 will ensure you don't "peg" the OEM MAF. "Pegging" the MAF results in blown motors and is possible with the use of 4# or 6# pulleys, particularly in the cool/cold winter months.

NGK TR-6 are great spark plugs which are inexpensive. The TR-6's will be in the desired heat range for either a 4# or 6# lower. Gap them to .034"-0.36".

Check to see if the intercooler recall has been performed on your truck. The '99-'00s where prone to leaking intercoolers. You might also want to clean your intercooler for piece of mind. Check out the "How-To" section for a thread to walk you through it step-by-step.

Invest in gauges also, vital but overlooked mods. I suggest a wideband air/fuel gauge, fuel pressure gauge and a vacuum/boost gauge. I'm also a big fan of the AeroForce Interceptor scan gauge due to its versatility.

Welcome to the addiction :thumbsup:
Thank you for the advice, I just bought those plugs also where do you recommend me getting the MAF and why would I need those gauges, sorry I'm still learning I'm 18

My friend has the blower and lower crank pulley but he tells me to put the top one first but he did the opposite ....?
 

DMassey

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Like throttle jockey mentioned, leave that upper pulley alone. The smaller pulley increases chances of belt slip, which will reduce boost. A lower pulley will add your desired boost, and the larger pulley on the crank will increase belt wrap... reducing any chances of belt slip.

DEFINITELY get an SCT maf or a Diablo MAFia. I found my BA2400 maf used in the classifieds forum here. Lots of good used parts there. Changing plugs & fluids was great advice, and defintely read the FAQ thread. It will answer questions you didn't even think to ask LOL.

BE SURE to get a tune for anything you do, as these trucks are sensitive to bad combinations.

Congrats on being 18 and choosing a Lightning!!!
 

throttle jockey

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Gauge aren't mandatory but they help you keep an eye on vital aspects of the engine which may be the difference between blowing the motor or identifying an issue that needs to be resolved before the motor blows.
 

SVT BLACKOUT

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Thanks bro! Sorry for bugging you guys but what if I put both pulleys and a new belt?

And where is the classifieds on this website since I saw that the MAF are pricey atleast the ones I saw , again sorry for bugging
 
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throttle jockey

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Just swap the lower. Yes, some people will swap to a 4# lower with a slightly smaller, 2.75" upper pulley which produces the exact same effect as swapping to a 6# lower without touching the upper.

Why swap two pulleys when the same result can be achieved by swapping only one pulley? And why swap a pulley to increase boost only to lose boost due to belt slip?
 

throttle jockey

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SVT Blackout... I prefer to refer to pulley ratio when discussing pulley combinations. In my opinion this is much easier.

To determine the pulley ratio all you have to do is divide the diameter of the lower pulley by the diameter of the upper pulley. For example, the OEM lower pulley measures 7.5" and the OEM upper pulley measures 2.93" (on a Lightning, the 02-03 HD is slightly larger).

7.5" / 2.93" = 2.56:1

What this means is that every one revolution of the lower pulley the upper pulley makes 2.56 revolutions. Swapping pulleys changes this ratio. Obviously, the more revolutions of the upper pulley, the more air the S/C is flowing at a given RPM.

Aftermarket lower pulleys generally increase the diameter of the pulley in 1/2" increments which produce two additional pounds of boost.

OEM lower = 7.5"
2# lower = 8.0"
4# lower = 8.5"
6# lower = 9.0"

To illustrate my point from an earlier post I made:
9.0" (6# lower) / 2.93" (stock upper) = 3.07:1 pulley ratio

Or, if you swap both the upper and lower:
8.5" (4# lower) / 2.75" (smaller aftermarket upper) = 3.09:1 pulley ratio

As you can see, the pulley ratios are essentially the same, just different methods to get to the same pulley ratio.

I hope this gives you a better idea :thumbsup:
 

wigginwilly00

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Market section at top of site.
Lightning Parts Buy/Sell - SVTPerformance

Just to piggy back off of the above advice, a wide-band is very very important if you plan on upping the boost. Installing a bad tune and not having wideband to monitor your air/fuel mixture is a recipe for disaster. It will need to be calibrated and monitored under "Wide Open Throttle." If you see it pushing past the 12.0 you may want to get another tune unless it's a kill tune.
A "Good" tune will make or break these trucks quick. Seen it happen way too many times.
I have been through several tunes and tuners. I've noticed a wide variety of issues and or perks from each tuner. JDM has far been my favorite tune and it was emailed to me. So you don't have to take it to a shop. However, you will need to data log the info and send it back to him for review.
 
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SVT BLACKOUT

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First off, before modding replace all fluids for piece of mind. Also, change the in-line fuel filter. This should be done every 2-3 oil changes. Its cheap and easy insurance.

Do not swap the upper pulley. In order to increase boost by swapping the upper pulley a smaller diameter pulley must be used which increases the likelihood of belt slip. The same can be achieved with a larger crank pulley.

4# or 6# lower pulleys are the norm. If reliability is of concern stick with a 4# lower. 6# pulleys are generally "safe" but they are more aggressive.

You'll need to swap plugs and retune for either a 4# or 6# pulley. You will also want to consider upgrading the MAF, especially since your truck is a '99 which came with a 80mm MAF from the factory. Use of a MAF extender such as the DiabloSport MAFia or an entirely new MAF such as the SCT BA2400 or BA2600 will ensure you don't "peg" the OEM MAF. "Pegging" the MAF results in blown motors and is possible with the use of 4# or 6# pulleys, particularly in the cool/cold winter months.

NGK TR-6 are great spark plugs which are inexpensive. The TR-6's will be in the desired heat range for either a 4# or 6# lower. Gap them to .034"-0.36".

Check to see if the intercooler recall has been performed on your truck. The '99-'00s where prone to leaking intercoolers. You might also want to clean your intercooler for piece of mind. Check out the "How-To" section for a thread to walk you through it step-by-step.

Invest in gauges also, vital but overlooked mods. I suggest a wideband air/fuel gauge, fuel pressure gauge and a vacuum/boost gauge. I'm also a big fan of the AeroForce Interceptor scan gauge due to its versatility.

Welcome to the addiction :thumbsup:

Hello I just bought the 90mm 2001-2004 lightning MAF will that be enough with the #6 pulley?
 
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throttle jockey

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The OEM 90mm MAF pegs at 5 volts. With a 6# lower you run the risk of pegging the 90mm. If you want to use the 90mm MAF you bought I recommend buying a MAFia. Otherwise buy a SCT BA2400/BA2600. Neither are mandatory but both are cheap insurance and highly recommended.
 

Robert Francis

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The 90mm MAF you purchased is large enough for the 6lb pulley you're thinking of installing. I'd recommend before spending a lot of money, you do a lot of research first - and locate a local shop with a dyno and a dyno operator thats familiar with Lightnings and talk to him for a few minutes.

Generally speaking, you won't need an upgrade to that 90 mm MAF with a 4lb pulley - and you may or may not with a 6 lb pulley. With your truck on a dyno, a capable dyno operator can tell you if your MAF is maxed out or not. The MAFIA and/or the SCT MAF's are "not" plug and play, and if you need one, you'll need a competent dyno operator to determine which "setting" on the MAFIA is correct - or in the case of an SCT MAF, he'll have to change some parameters in your computer program.
 

throttle jockey

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Get the MAFia or BA2400 now if for no other reason than to save money because:
1) you vent the block for pegging the 90mm
2) you realize you need one later then have to pay to retune.

Do it right the first time and be done with it unless you want to incur later cost to retune for it or build a new motor (worst case scenario).
 

SVT BLACKOUT

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Get the MAFia or BA2400 now if for no other reason than to save money because:
1) you vent the block for pegging the 90mm
2) you realize you need one later then have to pay to retune.

Do it right the first time and be done with it unless you want to incur later cost to retune for it or build a new motor (worst case scenario).

What about the ba2600?

I'm saving up
 

CustomBird

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...
To determine the pulley ratio all you have to do is divide the diameter of the lower pulley by the diameter of the upper pulley. For example, the OEM lower pulley measures 7.5" and the OEM upper pulley measures 2.93" (on a Lightning, the 02-03 HD is slightly larger).

7.5" / 2.93" = 2.56:1

What this means is that every one revolution of the lower pulley the upper pulley makes 2.56 revolutions....
I don't get this math. Can you elaborate? Is there a formula? Is there a variable missing such as rpm? Thx
 

WhiTriCobra

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It's almost like the ring and pinion vs one wheel revolution. but in general, the bigger the lower, the faster the upper will spin = more boost. Same if you just make the upper smaller, spins faster = more boost. But you can get X revolutions total by going to a bigger lower and stock upper. You can get almost the same X revolutions total if you go with a tad bigger lower and a smaller upper. So this bigger lower gets me 14 psi but if i go with combo option 2, not so bigger lower and smaller upper i can still get 14psi.
 

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