are stock heads on an o1 gm 5.3 vehicle worth getting worked? port polished and 3 angle valve job?

 

Moved to the Engine & Exhaust section.

 

Typical power gains from modding the heads is about 15-20rwhp all else being equal. Look for an upcoming Car Craft article that features a dyno comparison between the stock heads and our Stage 1 head package on a 5.3l engine. They saw about 18fwhp with the head swap only. Torque was also increased from bottom to top.
When coupled together with a mild cam, you could see between 50-75hp increases. The 5.3l engines really respond to cylinder head upgrades and cam swaps.

Richard

 

i got some heads not long ago. i gained nothing in the first 1/8 but picked up 5mph in the 1/4.

times went from 12.49@105 to 12.20@110 in comparibale weather. a 5mph 3/10 gain in the 1/4 was well worth it to me.

 

Would it be better to P&P the stock heads or get some aftermarket heads and bolt them on out of the box, like Patriots?

 

What kind of gain could I expect out of a set of youre heads with my Radix'ed 6.0 with the GT 2/3 Cam. Sorry to hijack youre thread.

 

PM sent.


Richard

 

your talking blown to N/A so i have no clue haha. i know you wouldnt want as much compression as i have. gains also depend on the combo. i have a full bolt on cammed LS1 and the heads were matched to my combo. im sure my results would have been different with another setup...im rambling cuz i have no clue. richard will hook ya up

 

Received, Thanks