lm7 with 243 heads
#1
lm7 with 243 heads
hey, I am new here and have been looking at some of the posts. I am going to be pulling the heads on my 03 sierra 5.3 lm7 and was considering putting on some 243 heads with a .040 cometic gasket to bring the compression to 9.8.
my concern was with torque, I use this truck as a dd and tow with it. so will I loose some bottom end running a 210 runner with a 2" valve??
also thought about just putting a 212/218 cam in with 918 springs and rods but am unsure about what needs to be tuned??never done it?? timing?? idle??
is ther a good cam that i can put in without a tune or springs etc.?? thanks
my concern was with torque, I use this truck as a dd and tow with it. so will I loose some bottom end running a 210 runner with a 2" valve??
also thought about just putting a 212/218 cam in with 918 springs and rods but am unsure about what needs to be tuned??never done it?? timing?? idle??
is ther a good cam that i can put in without a tune or springs etc.?? thanks
#3
ok that makes sense to mill them and use the stock .051 gasket, I was going to keep them at 64cc's and use a thinner head gasket of .040. is that right..you can do it ether way? makes sense to me?? compression wopuld be about 9.7-9.8.
how is your low end throttle response, did you notice a gain in hp and tq?
how is your low end throttle response, did you notice a gain in hp and tq?
#6
TECH Regular
#8
ok thanks, do I need a new cam gear to degree the cam or can I just run it strait up and slap it in. also stock converter ok or should I be looking at a less duration cam, dont want to smoke the converter if the tuning job puts the rpm up to high..
anyone have this cam?? what is your rpm at idle??
anyone have this cam?? what is your rpm at idle??
#9
TECH Regular
ok thanks, do I need a new cam gear to degree the cam or can I just run it strait up and slap it in. also stock converter ok or should I be looking at a less duration cam, dont want to smoke the converter if the tuning job puts the rpm up to high..
anyone have this cam?? what is your rpm at idle??
anyone have this cam?? what is your rpm at idle??
#10
TECH Senior Member
iTrader: (59)
Degreeing the cam on these engines is really just done to make sure the cam specs are what they say they are. Rarely are they not. Put it in dot-to-dot, spin the motor over by hand a few times to make sure the valve timing isn't horribly incorrect, and you're good to go. With my 212/212 114 I idle at 700 RPM with some noticeable lope. But it will do 600 easily, but I have it turned up since it's a manual trans.