Well, I have more to do than I originally thought

[Oldschool]

When I pulled the head off of the Beast, I found some damage to a piston.  Foriegn object in the cylinder caused the problem.  It galled the head a little bit also.  Head easily repaired, piston will need to be replaced. Here is what I am thinking.  I can buy sets of 4 pistons, but not a single piston.  It is currently running Wiseco 10.5 - 1 compression forged pistons.  I am tossing around the idea of replacing the entire set of 8 since I am this far into the deal.  If I replace the whole set, I am looking at maybe going with 11.5 - 1 forged pistons. I am running aluminum INDY heads with full CNC porting.  Fuel is not a big deal really since I have access to great octane booster and a race gas pump (104) within 5 minutes of the house.  That said, is the increase in power worth the extra $$ and time it would take to do the swap.  Any ideas on how much of a power increase the extra point of compression would be?  20 HP or 75 HP? Or would it be the best to buy 4 pistons and just use the one I need and put it back together the way it is?  All opinions welcome.....        

[nivvy]

the general rule is 25hP per 1 point of compression..... how high is your duration at .050....

I know a guy on moparts I was gonna buy his heads and he is 11.5 to 1 also on pump 93 with a 276 @ .050 cam with no issues...

[nivvy]

also jeff at modern cylinder head said he can add some cc's to the heads to lower compression some..... I may go that route to keep a closed chamber design.... 

[hemiken]

Hey Ken,

What is your cylinder size ?  I see Wiseco piston sets on e-bay from time to time and that is where i picked up my set of new Wiseco 572 Hemi pistons from and they cost me $100 for the set, you may be able to get lucky and find another full set.  What is the cost of 4 Pistons ?

[femtnmax]

Food for thought:  I have had more than once bought ONE replacement piston from the manufacture, told them the piston weight, and received a piston that was not even close.  They would tell me the mold, material, etc had changed and that was the best they could do.  So buying one or 4 pistons may not work out.  If your not replacing all 8 as a set, I would definitely check weights, or you could have engine-vehicle vibrations at one or two harmonic frequencies, say for example 40 and 75 mph in top gear. 

[Chryco Psycho]

I would just match the piston you have , buy 4 , make sure the piston weight matches the one removed & you will have 3 spares
 you detuned the beast to get where you are why are you wanting to back the other way , 10 second 1/4s not enough for street car 
 you seem to have a good reliable pkg , why mess with it
 if you want to step back up go all the way & run in the 7s again

[Aussie Challenger]

     Everything said above, balancing is a must but you will need to make sure that the piston dia., piston pin height & deck height match as well.
  You have a sweet car that keeps the MOPAR banner flying high, don't take short cuts.   

[nivvy]

I cant believe they cant balance 1 piston to weight... my buddy dropped a valve and trashed his indy head.... had the head repaired and borrowed one of my pistons till he got a replacement he needed..... both pistons were J&E and 4.375 bore.... he ran 8's on motor with no problem with my piston.... 

[vinb]

I agree with femtnmax & CP, I can't see why it would be so tough to make you another piston or two. Since you have the engine apart send them one good piston and have them make you one..
Your car makes good power ,why mess with a good thing..
Have your machine guy give them a call direct..
Good Luck.....

[71chally416]

I've Heliarc welded the tops of pistons on race motors several times. Once even on the tow vehicle that had a 500 cube BB chevy motor that had milled piston tops that were only .150" thick. It collapsed from a bad load of gas laced with ethanol. The old carb'd motors don't adjust for that like the new ones do.  Couldn't find a matching piston so I welded it up and it's still running fine a year later   As long as it didn't screw up the ring lands I'd weld it and grind it flat and put it back in. This is a piece of the piston top from the truck motor>
   

[moper]

I'd order the set of 4. I'm assuming they are 2 right and 2 left in that set... not all 4 the same side. My racer buddies always order 12 pistons if they know they are racing. Then have them all balanced at tthe same time, and you have spares.

[vinb]

Oldschool, how are you making out with your piston deal??

[Oldschool]

Oldschool, how are you making out with your piston deal??

I am gonna finish pulling it apart after the first of the year and decide from there....       

[vinb]

Yea, I got mine apart at the shop now and just waiting for the shop to measure the pistons & block to see if I'm going for new ones or not. I have no idea how many miles are on them..
.030 now  , don't want to go .040 right now....
Just want to get the thing back together so I can start on my next engine, probably a 360 stroker or maybe a 10.5 to 1 340 something from the left over SuperStock stuff, don't know yet...