[UrHookUp]

My question, Which is best to use? I have option to use 2# or 4# lower. Here is a list of what I have:

Heavy Duty CNC Machined Aluminum Relocation Bracket
CNC machined billet aluminum aux. idler pulley
(3) 100mm Idler Pullies
(1)90mm Idler Pulley

Kit Includes

- LFP QC Upper Pulley Kit
- LFP QC Upper Auxiliary Idler Package
- LFP QC Lower Crank Pulley Kit
- Your Choice of a 2#,4#,6#,or 8# Pulley Ring
- 14mm Hex Head Tool
- Allen Bolt Hardware
- Proper Sized Alternator Pulley

I'm already at 15-17psi

What do you all think? which lower should I go with?

[Baldsnake]

My track spec'ed '03 has been sitting in garage for 3 months while broken leg healed. Just before accident the local A holes at my Ford dealer zapped my chip while downloading a recall....anyway just had it retuned. 91 degree day....500 RWHP and 506 TQ. 2.93 upper/4# lower, early Apten port, JBA shorties, C&L cold air, Accufab TB, Bassani X's and baffels removed. 60 degree day would have added 15-20 on both HP and TQ. If I did not have a Corvette C6Z06 jones I would cam it and go crazy with brakes/cage and cell. Even my Mr. Ford...Blue Oval tuner just bought a Z....most amazing ride for the dollar I have ever driven. Cobra is a beast but handles like a Mustang.

[03svtsnakevert]

Originally Posted by UrHookUp

My question, Which is best to use? I have option to use 2# or 4# lower. Here is a list of what I have:

Heavy Duty CNC Machined Aluminum Relocation Bracket
CNC machined billet aluminum aux. idler pulley
(3) 100mm Idler Pullies
(1)90mm Idler Pulley

Kit Includes

- LFP QC Upper Pulley Kit
- LFP QC Upper Auxiliary Idler Package
- LFP QC Lower Crank Pulley Kit
- Your Choice of a 2#,4#,6#,or 8# Pulley Ring
- 14mm Hex Head Tool
- Allen Bolt Hardware
- Proper Sized Alternator Pulley

I'm already at 15-17psi

What do you all think? which lower should I go with?

You have to be careful here...the stock eaton is at max around 15-17 psi...to try and push more out of it you would not see the benefit...a popular combination is a 2.76 upper with a 2# lower...and I noted that it comes with the alternator pulley, that is great...did you already do the boost bypass mod as well?