xe273hr cam
10-12-2014, 11:59 PM
#1
xe273hr cam I recently got my motor rebuilt but motor is not making the power that it should with a small cam and headers. I recently got my car tuned and he mentioned that the stock pushrods were not long enough for the valves to open and close.is this true? He also mentioned I may need to change springs (stock ls2 springs). Just wanted some opinions before I order some push rods and springs. Inputs wanted. Thanks!!!
Last edited by jthom5s; 10-13-2014 at 12:26 AM.
10-13-2014, 07:06 AM
#3
Wait you put in an aftermarket .58x lift cam on the stock springs and pushrods? Change those out ASAP!
You shouldn't need longer pushrods to "open the valves" correctly. Most people with untouched heads go with the stock length 7.400 pushrods and are just fine. The ones who do go with a slightly longer pushrod at 7.425 do it for more preload and quieter operation (which is debatable) but in no way is it done to actually open the valves to their full potential. The stock length will do that given you haven't messed with the heads.
Also, given the tuner's suggestion that the valves don't open enough with the stock length pushrods make me think he's not exactly "knowledgeable" in the LS business and kinda question the tune also on your lack of power.
You shouldn't need longer pushrods to "open the valves" correctly. Most people with untouched heads go with the stock length 7.400 pushrods and are just fine. The ones who do go with a slightly longer pushrod at 7.425 do it for more preload and quieter operation (which is debatable) but in no way is it done to actually open the valves to their full potential. The stock length will do that given you haven't messed with the heads.
Also, given the tuner's suggestion that the valves don't open enough with the stock length pushrods make me think he's not exactly "knowledgeable" in the LS business and kinda question the tune also on your lack of power.
10-13-2014, 01:00 PM
#5
224/230 @ .050 .581/.588 114 LSA
You need to get some good springs on that car immediately and the hardened pushrods are a good idea as well. Wouldn't be surprised if you have some bent ones...the stock pushrods are often bent on stock cammed engines I've taken apart.
You need to get some good springs on that car immediately and the hardened pushrods are a good idea as well. Wouldn't be surprised if you have some bent ones...the stock pushrods are often bent on stock cammed engines I've taken apart.