I tune for one of my buddies shops here in CA and this last truck I did surprised me, so I thought I would share the combo set up. Generally speaking, I don't recommend modding an NA 4.8/5.3 besides headers and maybe a CAI.

However this one surprised me - 1999 5.3, 228R cam, 799 heads, headers, and Holley hi-ram, through an 80E - 387rwhp.

Graph is below.

 

I�d almost bet a mid-ram would work better but those are good numbers for a 5.3 and a 228r.

 

4.8 pistons by chance? What exhaust? That ***** impressive! Damn near 400whp. Sea level must be nice lmao

 

It's a stock 99 short block. Speed Engineering headers and dual 3"

Yes sea level is nice for power and track times.

 

where do you tune out of ? I need a retune but the tuner I used is no longer available.

 

San Bruno, CA

 

Why would a mid-ram work better for a smaller engine? If you want to rev it to the moon, maybe...

 

Ported heads? 91 octane fuel? Looks like a high strung set up.