Thread: Engine work??
07-29-2013, 07:24 PM #1
Well i just had a blown head gasket do to an over heated, so i pulled the head and notice that my block could use a shave to be safe!! Since i have to pull the pistons and crank i though that is not a bad idea to replace pistons? What pistons should i run and why?? Since im going to have the engine apart what else should i do? Suggestions??
07-29-2013, 07:42 PM #2
CP 9.5s, I saw you're head... You dont have to shave the block for that IMO. Just have the head decked, valves cleaned up and a valve job along with a new gasket.
07-30-2013, 02:14 PM #3
07-30-2013, 02:23 PM #4
07-30-2013, 02:33 PM #5
Choices choices...........If you are putting new pistons in it the CP's for sure. But if you plan on going turbo in the future then you will want the lower compression ones 8.4:1 if you will stick with a supercharger then 9:5:1's.
If your doing the pistons then you may wish to consider new rods as well. Then you need to think about rebalancing the crank for sure. Then as you are doing that, maybe a lightened flywheel.....The list goes on as to what you can do once you start playing with the bottom end of the engine. How deep are your pockets and what do YOU want out of the ski in the end is what you need to ask yourself before diving in.
07-30-2013, 02:38 PM #6
07-30-2013, 02:48 PM #7
Straight edge the block not hard don't guess. you dont want to do anything to the block other than skim it straight Cp 9.5's are the way to go anything you do perfect piston choice. Going to lighter valves are all in combination with rpm, setup,timming,cam your running, boost etc
07-30-2013, 02:49 PM #8
Keeping the OEM Pistons is not a bad call at all. If the bottom end on yours if fine then why disturb it and risk hassle and problems.
Upgrading the valves (IMO) will give you greater long term reliability as they seem to 'drop' less than OEM ones. The rear of the valve (depending on who's you go for) will be contoured differently and will aid flow past the valve and into the head. Being lighter than OEM you are reducing the moving weight of the valve train and that with other mods will allow you to rev the engine higher and will reduce the risk of damage over the OEM ones.
Again, the question is where do you want to end up with YOUR ski?
07-30-2013, 03:18 PM #9
if your pulling the bottom end apart, go with CP pistons, I never understood why people disliked stock pistons until I burned a hole in the exact same spot as others have. Now I only run CP.
07-30-2013, 03:20 PM #10
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