I'm going to swap the heads out on my 04 5.3L 4x4 ext cab. it has 4.56 gears on 35's. This is a daily driver and takes long road trips so it needs to be fairly dependable.

Cam it has in it now is 214/218 .559/.562 111LSA

lift at Ratio's
on 1.7 = .559"/.562"

on 1.8 woold be .591"/.595"

The springs will be pac 1518 .650 lift. or use other? I have seen pac 1218 but the 1518 is a more durable spring in the long run from what I have seen just has more lift than needed.

now the heads will be CNC Ported 5.3 heads from SDparts

flow rates
LIFT INTAKE EXHAUST
.200" 144cfm 111cfm
.300" 199cfm 141cfm
.400" 244cfm 180cfm
.500" 280cfm 203cfm
.600: 286cfm 215cfm

Also going with 1.8 would the 7.400 push rods be close enough? also what else should I exspect with the greater lift or would be be worth it to change the ratio? anythoughts would be great. I have read the 1.8 WILL clear the valve covers,anyone tested this?

 

no one?

 

Still no one? okay then how durable would the 1.8 set up be? would the longevity be the same as the 1.7?

 

People usually recommend getting a cam already ground for the stock 1.7s.

1.8/1.85/1.9s work well with stock type cams, but might be sketchy with a custom cam.

 

I wouldn't bother with the 1.8's. At .560, the heads probably flow around 283/209cfm which is hardly a difference from the numbers at .600 lift.

 

Would it help low thru mid power? I honestly don't run the RPMS very high. Its a lifted truck and not a speed truck. If there is no noticable power with the heads and going to the 1.8 I'll just do heads adn 1.7. I'm just looking for all I can get while doing the head swap with out killing overything else for the daily driver.

 

I don't have firsthand experience, but I imagine it wouldn't do much for it. Stock rocker arms are the most reliable, so just stick with them. If you feel the need to upgrade, you can modify the stockers with a trunnion upgrade kit from Harland Sharp or Comp Cams.

 

okay new question, going back to the 1.7 from the 1.8 would the little flow make my tune flip out or would it relearn itself and act and drive right?

 

I would think it would be ok. Go for it and see if you get codes.

 

being so little I wouldn't think so ether but I'm a newb at this stuff.