Ronin8002
Explorer Addict
- Joined
- March 23, 2003
- Messages
- 4,416
- Reaction score
- 15
- City, State
- Virginia
- Year, Model & Trim Level
- 2008 XLT Ironman
4.0 piston rings..replace or not?
I don't have my chilton's manual handy and had a question about piston ring replacement:
I'm taking my 4.0 engine down to the block next month sometime so I can do the following:
-replace my cylinder heads with P&P heads (which include stainless valves and dual valve springs)
-replacing the stock cam with the compcams 422
-replacing stock rockers with hardened cups and custom length chromoly pushrods
-porting the lower intake
-replacing my granatelli MAS with an 80mm pro-m MAS which is calibrated for..
-24 pound injectors that I'm installing
-As well as a bbk supercharger
-190 lph fuel pump
-MSD DIS-4
-and maybe a ZEX nitrous kit with a 75 shot later.
I ran a compression check not too long ago and came up with 150 on each cylinder.
I am wondering if I need to replace the rings, if only to make the gap bigger to deal with the increased heat and pressure. I am not planning on honing the cylinder bores because I'm keeping the stock pistons.
Do I need to replace the rings, and if I do, is this something that I can do myself (I have a lot of tools available) or do I need to get involved with a machine shop? I don't want to do all these mods only to have the rings blow out 20k miles later (or less), so all suggestions/adivce/comments are welcome.
thanks!
-James
I don't have my chilton's manual handy and had a question about piston ring replacement:
I'm taking my 4.0 engine down to the block next month sometime so I can do the following:
-replace my cylinder heads with P&P heads (which include stainless valves and dual valve springs)
-replacing the stock cam with the compcams 422
-replacing stock rockers with hardened cups and custom length chromoly pushrods
-porting the lower intake
-replacing my granatelli MAS with an 80mm pro-m MAS which is calibrated for..
-24 pound injectors that I'm installing
-As well as a bbk supercharger
-190 lph fuel pump
-MSD DIS-4
-and maybe a ZEX nitrous kit with a 75 shot later.
I ran a compression check not too long ago and came up with 150 on each cylinder.
I am wondering if I need to replace the rings, if only to make the gap bigger to deal with the increased heat and pressure. I am not planning on honing the cylinder bores because I'm keeping the stock pistons.
Do I need to replace the rings, and if I do, is this something that I can do myself (I have a lot of tools available) or do I need to get involved with a machine shop? I don't want to do all these mods only to have the rings blow out 20k miles later (or less), so all suggestions/adivce/comments are welcome.
thanks!
-James