FirstGen

iTrader: (10)

Ok, so I have a 2002 6.0l LQ4 and since the only difference between the LQ4 and the LQ9 is the compression I want to mill the heads to recover this.

My question is with the 01 LS6 cam I have the base circle is .520 which is .030 smaller than the stock (.550) then I also want to mill the heads about .030 for higher compression. According to the articles on this forum, am I right that I want to run chome moly 7.35 length push rods?

Also can anyone tell me what compression I will have using rough math for this motor after shaving the heads?

Thanks for any input.

FirstGen

iTrader: (10)

anybody know?

1fastWS6

iTrader: (3)

Stock PR is 7.380".....

Your increasing the req'd PR length by going to a .030" smaller base circle cam, then decreasing the req'd length .030" by milling the heads. So the stock PR length is what you ideally need. The 7.400" will be .020" too long, and the 7.350"s will be .030" too short. The stock lifters can handle a small increase in preload.....get the 7.400's.

Do a search on the compression ratio question, there's a HUGE thread on that.