does anyone know the factory rating for a 01 4.8 liter and a 01 5.3 liter engine. i bought what was supposed to be a 5.3, but i think it is a 4.8 instead.is there a big differance in power from one to the other?i hope not

 

according to factory 4.8 is 275 and 5.3 285 but torque is much better on 5.3 the 4.8 isnt so bad if you got a regular cab , unless you have a ext cab well then that sucks. welcome to the site well be glad to help you with anything.

 

thanks for the response i bought the engine trans and all the acc's to try and put it in my 97 s10.i did not get the pcm though and i am tring to find out what the engine is so i can buy the right pcm.do you like hp tuner or ls1 edit better i am going to buy one of them to romove the theft-deterrent and delete the bcm codes on the pcm.also do you have any thoughts on what type of motor mounts might fit what i am doing.you guys are great thanks for the help.

 

The 4.8 and 5.3 use the same block and heads. You can pull out a spark plug and look inside at the piston top. The 4.8 has a perfect flat top while the 5.3 has a dish. The 5.3 piston will have a raised ring or ledge around the outer 1/4" of the surface while the middle is lower. Basically the 5.3 has a lip on the outside of the piston top while the 4.8 doesn't.

Torque will be up pretty good on the 5.3, and but peak HP difference won't be that far off. Down in the 1500-3000 rpm range, the 5.3 will be noticeably stronger.

A 4.8 on a S-10 would be pretty strong, but if you paid for a 5.3.....

 

Short of having the VIN, looking at the piston is the only way to tell the difference without dis-assembling the motor. The salvage yards have a service bulliten describing the probelm....it's as BigTex said.

 

I think on the back of the block, maybe behind the flywheel it will say 4.8 or 5.3

 

not sure if i'm right or not but i think it says 4.8 an 5.3.but like they said the tops of the pistons are different.4.8 flat 5.3 dish.the pcm for the 5.3 will work with the 4.8 and vise versa. good luck.

 

I stand corrected, this was on the back of my 4.8

 

The 2001 4.8 is 270. Sorry for the petty correction, I just couldn't help myself.

 

is that how much they really make or are they under rating them has anyone dynoed a stock 04+ 5.3 how much rwhp do they make?