BEASST99

First off what is the deal with me hearing about how LS1 owners are putting LQ4 heads on their engines? Do they make good power and do you have to mod anything to get them to fit? Second where can I get some and about how much do they run? Also what should I do to them in order to make some real power?

Thanks,
Adam

Old SStroker

The LQ4 (Chevy and GMC Truck) and LQ9 (Caddy) 6.0L heads are in the same engine family so yes they bolt up to a LS1.

The big thing with them is they flow better than LS1 heads and very good ported units with 2.055" Valves are 330+cfm so 100 extra cfm will definately help. This is mostly due to port location and shape.

The bad thing is that thy have a large combustion chamber. That large chamber can be milled .040 to get it down to 60cc's or so so your compression is back to where it belongs.

They bolt up to a LS1, you can get them off any 6.0L truck in a yard, Valvegod (that's his screen name) is a good place to start.

You'll see alot of info here on the 6.0L heads. Check that out.

Ackattack

Another option is the 5.3L heads (don't know the code). They seem to make a lot of power too.

ls1290

iTrader: (20)

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Old SStroker:
<strong>The bad thing is that thy have a large combustion chamber. That large chamber can be milled .040 to get it down to 60cc's or so so your compression is back to where it belongs.
</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Would not milling them 0.040" produce chambers of about 65cc's from 69cc's? To drop 9cc's seems quite a bit for milling 0.040".