rcsb4.8to6.0

I get 15.2 mpg city driving with the 6.0, 2600 stall, and fms 220/220 cam. Get a 6.0 and a good tune and mpg shouldn't be a promblem if you can keep your foot out of it.

gonzo 6.2

iTrader: (8)

I get 18HWY and have got 15 town/country.Checked it today and got 14MPG town/country driving with my foot out of it.I towed a newer Sblazer 50 miles in that run(about 5K LBS TRUCK/TRAILER.). I get 13.5 when towing autos long haul.It was 11 MPG. with the 5.3.Winter fuel always costs about 1 MPG.

F8L Z71

With my 226/.535/112 cam and TT3000 I was getting 15.5mpg after a good tune I was stripped down a bit but it didn't seem to change much since I was over 5000lbs daily driving no matter what else I left in the garage. LOL

Bone stock I never got more than 16.5 average.

I wonder how you 6.0L guys are getting such good milage. My buddies HD only gets 11.5 and that was with my foot out of it. He is stock with a K&N intake and Flows.

gonzo 6.2

iTrader: (8)

HDs are very heavy and heavy trans,gears wheels ect.My 5.3 with bolt-ons was getting 19HWY 16 town /country driving.With the 6.0 i lost 1 MPG each HWY/town driving.I picked up mileage towing with the 6.0.It is easy to kill 5.3 mileage,just go bigger tires.

F8L Z71

He did that too. That's the last time I measured 11.5mpg.

straped for cash

Ok, an engine is most efficient at its tq peak. The 5.3 must spin faster to match a 6.0 tq peak. Bolt ons for the 5.3 move the effective tq range higher in the rpm range to fill the smaller cynlinders with enough air. The higher engine speed = less fuel efficient. Tq allows the 6.0 to work less at lower rpm. Sure you can set the 6.0 up to rev but then it will consume more fuel than the 5.3. A mild 6.0 might not match a higher reving 5.3 (if your reving the hell out of it, high stall, short gear, and holding gear) in all out 1/4 time, but it should match or beat it in most other situations. Smaller engines just don't deal well with big weight .

SimpleManLance

iTrader: (9)

well you guys are starting the change me over. i e-mailed the junkyard that has my engine to see if they buy engines. if they would by my 5.3 then it could off set some of the cost of the 6.0.


it would be all done by me, friends and my girlfriends mom's boyfriend who owes me a favor for coating his garage. he has restored and built old cars so it shouldn't be that bad.

power is a goal. if i do keep the 5.3 i would be really disapointed in myself because i know what i want(ed) to do to the truck and how fast i want(ed) it to be. runing a low to mid 14 in my truck wouldn't cut it. but like you said cost. i don't really want to save money just put it toward other things (new quad, and now a Jet ski, as of last night.).

at first i wondered that too. my dad has a 03 hd and he gets 10-11. and he never gets on it. that was sorta stearing away from doing it too beacuse with the plans i wanted i would need a 80e too. i guess there is a big difference in weight between the trucks.

thanks guys for the imput. you all defently have me thinking again. im just going to put the truck on hold for a little bit and try not to spend my engine money. my buddy(P.O.R.N.) is putting a a 216/220 .525/.532 114lsa with 1.85 rockers in his truck really soon so that might give me some ambision to get something done. i defently dont want to be beat by him. well not for to long at least.
well atleast i will always have a fast truck sitting in the spare bedroom closet(all my parts).

gonzo 6.2

iTrader: (8)

Have you ran your buddy P.O.R.N ?What does he have? It will be a good test for you to see what his cam will do for him.

SimpleManLance

iTrader: (9)

before my new mods he would pull right off the line a half a truck then we would stay even till i slowly ran him down top top end!! Now with my new mod i pull a truck and a half off the line and stay that way till i pull top top end.

His mods now: 01 5.3 4.10 K&N fipk, true dual no cats, predetor chip.
soon mods. 216/220 with 1.85 rockers, trailblazer stall, nelson tune, and maybe trolley lt header.

his 4.10 vs my 3.73's is what helps him so much..

here is the top end pull. he might have let off alittle towards the top, but we will never know. from i would say 65mph

gonzo 6.2

iTrader: (8)

You kill him on the top end.I tried 4.10s,It felt snappy would roast the tires easier.But when I raced a buddy it seemed the 3.73 pulled better because of the use of the 6.0 TQ. Maybe the little 5.3 like the lower gears.Also i think the 1.8 rockers are a waste of money for our mild trucks,make up the lift difference with the cam,the higher ration rockers take away low end and of course so will the cam slightly.If you want to slaughter him save your bling and your labor help for a 6.0,shove your cam in there and you will be done.