Stupid head question...

[oleshifty]

Looking for a set of heads for the new engine setup. Looking at tanz post on different LS heads.


243's seem to be the most sought after head. They have a combustion chamber of 64.45cc.


706's are a dime a dozen, and have combustion chamber of 61.15.



Wouldn't putting a set of 706's on any engine bigger then a 5.3 net more power then 243's because it would have a higher compression ratio?


I have been looking at ported 243 heads thinking I was going to gain power, but realistically, I'm going to lose compression because my 5.3 is smaller then a 5.7, so is it possible these will LOSE power over my stock crappy 706 heads? Or will the bigger port volume more then make up for the lack of compression? I'm looking for a set of N/A heads, was hoping to end up with a 10.5 or so compression ratio.

[oleshifty]

anyone?

[truckinL33]

I would deck the 5.3 heads and port those. You'll retain compression, and get them to flow very close to ported 243 heads if not the same as 243 heads.

[oleshifty]

Ya, I bought a couple "how to build ls1" type books, and have been doing a bunch of research. Think that's where I'm going. I'm just worried about having my heads worked, that something won't be right with clearances. I am not pulling engine out, so it will be hard to check everything myself. Was trying to get something tried-and-true to be safe.

[truckinL33]

I port cylinder heads, if you want something that will work without worries and perform very well.

[o2camaross]

Hey truckin how much do u charge to port a set of 5.3 heads? Can u mill them too?

[oleshifty]

pm sent

[Botlfed]

why not just P&P some 862s, mine seem to do pretty well.

[oleshifty]

ya...that's the current plan. Or just breaking down and buying the patriot 5.3 stage 2.5 heads.


Problem is I want to tear apart/rebuild in a weekend. Don't want the motor apart for weeks, so I'd need to find a cheap set of 862's to have built before I tear into motor.

[Botlfed]

so I'd need to find a cheap set of 862's

ahem!!, i might know a guy