What is the exact difference in the 4.8 and the 5.3 in the 2000 chevrolet trucks? Does anyone else have some good time to post with a 4.8? Everyone i see in here is running 5.3 or bigger. I am a runt and want to get the better edge on those red light street races. Have a few things done and looking to spend a little more for a better edge. I have the gears coming so don't need that as a suggestion and i don't want any headers. Once i have the gears installed i will do all the free mods and see if i have and improved gain. Thanks for the help....

 

The difference is the 5.3 has a longer stroke,thats where the extra hp and torque come from.I believe they are the same other than that.As far as suggections on what to do....I think a nice stall converter would be good.You can knock of as much as .5 off your 1/4 mile with a good stall.Most everyone seems to like the Yank TT 3000,myself included.Really good driveable converter.When you do the gears are you intalling a pos unit also?I wouldnt do the gears without adding a pos as well...eaton make a real good unit.

 

The reason i was asking is cause i was wondering if the cams were the same? Was thinking that was the difference in the motors. I really want to put the cam in my motor but don't know which one to go with. I want a good street cam. We tried the ZO6 cam already and had no results that i enjoyed looking at. As for the gears, i am not installing a posi unit and really don't want the stall cause i don't want to replace the rear end. We are running the Yank stalls here and everyone is changing to Eatons right now. The Eaton is slowing everyone down by .2. And i don't want headers cause my converters are staying in the truck. If i gut the converters, then i know i will go ***** to the walls with it. But so far, staying as much of a sleeper as possible....

Thanks for the help....

 

So you have tried a LS6 camshaft???? People have given the Z06 cam in trucks a bad reputation but i've spoken to two people how have done the install and were impressed. Why not install some shorty headers if you don't wanna change much or some Other Guys headers if you don't mind needing to have some welding done that will not affect your catalytic converters.

 

You have a few misconceptions that need to be cleared up first...

1. You CAN easily keep the cats with some long tube headers and with shorty headers. The collectors on the LTs get welded in place just before the cats. Shorty headers are direct replacments.

2. When you install gears, install an Eaton posi unit. The factory G-80 (if you have one) sucks hard-core. It doesn't lock after about 25MPH and they break easily. I don't see how a good posi unit will make you slower in the 1/4. With a 4.10:1 gear set and a stall converter there is no way that the stock G-80 will be able to lock up.

3. A stall converter will not cause your rear axle to break. F-body guys break theirs b/c they are 7.625" and have very thin gears. Most of the ones who break them are M6 cars and the initial shock of the clutch drop is what causes them to break. An A4 launches much softer and breaks far less often on those cars.

4. Z06 cam is for a <3400lbs car, not for a >4200lbs truck. The powerband is way to high. Consider something like a 212/218 ~.520" lift on a 114lsa or a 216/222 ~.535" lift on a 114lsa. Those are nice truck grinds for great midrange.

Now that is cleared up, mod wise... ASP pullies are nice. Free up your air intake somehow as a stock box is restrictive. You can add a UPD lid and saw the bottom off. You could also get the stock TB ported as well. A high flow MAF meter is nice for an N/A application. Some sort of advanced computer programming works well also such as an off the shelf Predator by Diablo or LS1 Edit for the hard-core tuning.

 

would thoes cams (212/218 .520") require the use of LS1 edit for drivability. I know LS1 edit makes gains on anything. But back to the topic, why does GM make the 4.8 and 5.3? Basically both are the same I havn't driven a 4.8 but I couldn't imagine it being a cheaper option. GM for the last 15 years has been a textbook definition of globalisation but they have 6 engine options in full size trucks. Not that i'm complaining it just doesn't follow the GM logic we have shaken our heads at for years.

 

Well any internal mod would require some tuning. To what extend I can not tell you.

My 5.3 Z71 is underpowered also. GM should just dump 5.3 from the 4x4 trucks all together in favor of the 6.0 low-output. The HD trucks should come with the 6.0 high-output. I like the Duramax and the 8.1. The 8.1 is still way wuss for just shy of 500 cubes. 340hp or so? Come on, it needs more than that.

Also, GM needs a light duty 5 speed auto. That will make for better fuel economy.