i see you have a drag car, so you know how to make horse power.
i say go with 4.11 gears and get rid of the 3.73
go out and sling some mud.

 

yea my first thought is some gears as well. for my truck the underdrive pulley made a nice low end gain, along with efans. besides those mentioned, a cam for stump pulling and boost will get the bottom end power you want.

 

with a 3.06 low gear and 3.73 in the rear that should be more than enough gear multiplication to get this thing rolling,it needs more torque.4.10 would kill mileage.

 

Increasing the timing (A Predator tune in my stock 5.3L made a huge low end difference).

Long tube headers (don't waste any money on shortys) Thorley tri-Y are designed to help low end.

Higher stall torque convertor (this will solve all the low ends problems, and tires start to wear out quicker)

I would not recommend installing a cam. I could be wrong, but I've never herd of anyone gaining off idle torque with a cam in these motors before.

But Crane does have a "truck cam" 200/200 .502/.502 113 LSA it might work, never herd of anybody using one.

Grind #HR-200/295-13 0A

Quote from crane
"Excellent profile for that"stock type idle" with super low-end torque for Corvette, Camaro/Firebird plus sport trucks w/4.8L. Pulls hard to 5,000 RPM. Perfect for stock automatics. Basic RPM 1500-5000"


6.0L - I think it is the best mod out there. My 6.0L with a mild cam, has more torque at 1100rpm then my 5.3L had at 1800rpm.

 

Radix

 

what is the stroke of a 6.0 versus a 5.3?
anyone have any smokin deals on a supercharger?
what converters are you using?how loose is it?what does it do to mileage?
sorry about all the questions but this thing has me bummed out.
i even whas looking at new trucks this weekend.

 

Vhp 044 I Have Heard Great Thing About There Cams

 

who is Vhp?

 

6.0L stroke is the same as a 5.3L but the bore is 4.00" vs the 3.78" 5.3.

6.0L's have higher flowing LS6 style heads, plus the larger bore unshrowds the valves. 6.0Ls have tons of torque.

I am using a converter made for a trailblazer 4.2L, it stalls to 2650-2800 behind the 6.0L, Its a lot looser then stock.

Mileage with 6.0L + stall is the same, maybe .2 mpg worse, but its 1.8 mpg better on long highway trips (never ever has to down shift for hills).

 

I'd get some Headers summit has some full length Hedman Hedders part# HED-69680. I was thinking about getting a pair of these myself whenever I got 500 bucks. E-fans would also give you some low end. I've never heard anyone complain about how slow their 5.3 is to the point of looking for another truck. Maybe you could look in the direction of the Joe Gibbs Chevy.