i have a daily driven 03 sierra ext. cab that i just pulled the 4.8 out of because i had to rebuild the tranny.my ? is i have a low mile 5.3 that im putting in with the rebuilt tranny. i have a 04 z06 cam,home cleaned up heads,cai,and a borla muffler. will i need to upgrade the injectors for this swap? i do have a 6.0 going into my other truck (01 rcsb) that i can pull the injectors out of it need be. remember this is my daily so thats why i went with this cam and didnt want to make it to radical, just some more power.
thanks in advace fellas

 

Doubt it. The z06 cam is very mild it probably won't max out the injectors. Also the injectors in the 4.8, 5.3 and 6.0 are all the same. You would have to get injectors from an 8.1L to be an upgrade.

 

no. Keep the injectors

 

thanks for the info guys. i appriciate it.
one more question i dont believe im goona need a tune for this right?

 

Should run on the 4.8 tune but it would be a good idea to tune it for a 5.3

Edit: wasn't thinking about the cam.
Should still run and drive. but you'll want to tune it.

 

I think it would be good idea for a tune adjustment going from a 4.8 to a 5.3 with a cam.

 

im still running on my stock 4.8L tune with my 6.0... it runs very well on the 4.8 tune.. no problems.. no codes... using the same injectors....

so no you dont have to tune it... but like they said it would be best....

i need to get mine tuned but im waiting untill i get a cam or FI before i get a tune.... dont wanna have to tune it twice..

 

Wouldn't the VE tables be off since you're going up in displacement? I mean, I'm sure it will run with the 4.8 tune, but it'll RUN with the 5.3 tune, especially since you're putting a cam in it

 

im with him!!

 

you dont need the injectors...

but I do need a tune with my Z06 cam and 1.85 rockers...lol