I've got a 4" cat-back and I dont really notice lag. Maybe Im used to it, but it must not be bad..

 

If youve got a 4" cat-back there shouldnt be much lag at all. If you upgraded to a turbo-back it be virtually non existance.

 

The 6 liter is a small displacement engine for a diesel...There is no replacement for displacement...the 7.3 has 25% more displacement, that is going to be hard to make up, this is where some of the low end grunt is from...

All turbo engines have lag...

I better be careful here..The 6 liter is a great engine and has plenty of power, I tried to explain that the power is different from the 7.3...Differrent power bands...

 

According to Ford, the 6.0L torque 'comes on earlier and holds longer'

I know I can leave my father in law from a stop (7.3 but drw) and not see him again

 

Stock trucks yes!!! the 6 liter has more torque and hp...now modified trucks, different...

The power band is higher and it revs higher...I still haven't heard any 6 liter at the truck pulls yet, still listening..

I would like to see the torque curve of the 6 liters...got any charts

Mine develops, max torque below 2000...stock is 1600...but right off idle it is a torque monster...these are for the 7.3...

BK--what is max torque at what rpm???

 

Ahh, ok, modifications change everything

The max stock torque is 560 at 2000rpm

The max stock HP is 325 at 3300 rpm

The torque is over 500 from 1500-3300



BTW Mach, of intrest to you, I heard on TDS that a guy had all kindsa mods to his 6.0 (HUGE intake, exhaust chip and a home made propane system that was, apparently, not very accurate. He used the truck on the strip alot and of course blew it up.
The interesting thing is that the failure was a broken crank!

The trans. held up fine

 

OK..heres what i got the 7.3 makes max torque at 1600(525)...lower rpm for max torque, then it peaks and starts to fall off..Ok that makes sense..the 7.3 doe shave more torque and sooner then the power band of the 6...

mine seems like it has 500ft lbs at 800rpm off idle, I need to pull those dyno curves and see, I had them in my hands two days ago...I know my torque 'curve' is flater then stock...and wider...

He blew the bottom end, that is unusual, the rocker arms break on these, unless you have the powered rods..

usually the bottom end is the strongest part of an engine...

yea, I haven't heard too many tranny problems yet...That is great, because that is a beauty of a transmission...That is also why that truck is faster, the trans has alot to do with it...same as the Durajap...I raced one dead even...but mine has more power, his has more gears...

You got a good truck--No doubt...I may get another for the shop truck...That way i can get wild with mine...

 

It's funny you mention that it feels like the power starts at 800.

I agree with that feeling in my father in laws truck (7.3). When I drive his truck, from a stop I jerk my head!
I thought it was throttle response because my pedal travels over an inch before I get any GO. Im having that looked at for the second time right now

 

I had a 99 7.3psd and i was suprised how good it moved, i just got the 03 6.0 f-350 drw 4 door. from a light i think the 6.0 will waist the 7.3 now both where bone stockand the 99 was srw extended cab!!!!!!!

 

Bikenut,

My 03 Silverado at work (4.3l v6) is the same way. You gotta shove it to the floor just to get moving.

 

Throttle position sensor, there are all kinds of mods for that problem...Bikenut, isn't it a know on the new ones...There is all kind of slotting, adjusting, spring relieveing...