wkdivr

iTrader: (8)

What is limit you could go down to on a 5.3, and still be daily driver friendly? The Magnuson supplied one is 3.4. Could you go as low` as 2.9, 3.0?

whitt1

I ran a 3.25" pulley with my 5.3 on the street with good results,I also ran a 3.0",but saw very little increase in power with the 5.3 so i switched back to the 3.25".With my 403 I'm running a 2.75"pulley,but would'nt recommend it with a 5.3.

wkdivr

iTrader: (8)

Did you retune foe the 3.0?

whitt1

No,I didn't tune for the 3.0" and was afraid I wasn't getting enough fuel,so I switched back to the 3.25"with was giving 9 1/2lbs of boost.

wkdivr

iTrader: (8)

Wow!! 91/2 pounds! Yikes!! Looks like I'll probably retune for the 3.2, too! So...you thought you might be running out of fuel? Pump, or injector, or both?

whitt1

At the time I was suspisous that the fuel pump was a problem.I was running the original MSD boost-a-pump setup with the stock fuel pump and had just replaced my second fuel pump.Now I'm running a big Edelbrock inline fuel pump along with the stock pump and 57lb injectors,but I'm running 403 cid.

wkdivr

iTrader: (8)

I have an 04, with the Wallbro in-tank pump that Magnuson supplies. Think that would be enough? I'm looking at approx. 59-60 idle, and 56-58 at wot. That's fuel pressure, obviously.

whitt1

You should be fine with that setup and your 42lb injectors should be big enough run either a 3.0" or a 3.25" pulley,I'd go with the 3.25"my truck made 417rwhp with the the 3.25"pulley and about the same hp with the 3.0"with only a slight gain in torque.The 3.25" pulley is close to optimum with the 5.3,you start getting deminishing return after that.

wkdivr

iTrader: (8)

Alrighty, then. Thanks for the info. 'Preciate it!

03sierraslt

iTrader: (22)

Get Er Done Bill