Any idea what compression would be with stock shortblock and the 5.3 ls1 head???

 

Depends on if the head is ported and how much material is removed. Most ported 5.3's are in the 10.8 to 11.3 range. Usually, the chambers are opened up a little.

A stock 5.3 be higher compression due to the smaller chamber.

 

Does anyone know what the typical gain is from just bolting on a stock 5.3??

 

Probably nothing. They valves are smaller so you have to change them. 1 point of compression is worth about 20 HP. But it will all equal out to the same if not a loss of HP. Best bet is to get them ported and some new valves to use them to their full potential.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by TooSlowFiveOh:
<strong>Does anyone know what the typical gain is from just bolting on a stock 5.3??</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I think stock 5.3's have 1.84 inch intake valves. This is too small to make good power. You'll want to get a 2.02 intake valve and good valve job at the very least.

If you have a set of 5.3's and for all the work involved think about getting a set of ported heads from >>>>>>>>>>>>> there.

TEA has excellent heads. TEA Stage 1's are very affordable and will make good power. Also the Stage 2's are nicely priced. If your going to swap heads, get a good gain out of it.

www.totalengineairflow.com