charlie97z28

iTrader: (2)

I have a set of 5.3 and a set of 843s wich one's would be better to port i know there are Better heads out there but doin this on a budget what's the biggest cubic inch I could go with and still make good power with either of these heads

ShevrolayZ28

iTrader: (4)

Are you planning to change the valves or mill them? I think stock for stock, the 5.3 head has smaller valves, but also has smaller combustion chambers...

charlie97z28

iTrader: (2)

Port and polished and valve job

garygnu

853s or 243s ?

01ssreda4

iTrader: (96)

I don't think he is referring to 243/799s however he could be.

OP whats your casting number on your 5.3 heads?

ChucksZ06

iTrader: (9)

If you are not going to mill the larger heads I would port the 5.3 heads and maybe slip in a larger intake valve.

charlie97z28

iTrader: (2)

The 5.3 heads are casting number 862. The other heads are 853 of a 99 trans am a buddy gave me

Golf&GM

iTrader: (22)

Kind of wondering the same thing. Subscribing...

charlie97z28

iTrader: (2)

Any body got any input?

30th6

iTrader: (6)

you could port the 853s and then mill them down,best of both worlds.

1'low92

iTrader: (5)

subscribing........i can get a set of 5.3 heads for next to nothing and have 853's on the car now with an ms3 cam and 90/90 setup. im curious to see what would be the better choice port the 853's or get the 5.3s and have those ported........decisions