Putting In Forged Pistons Only
12-06-2006, 11:25 PM
#1
Putting In Forged Pistons Only I've been looking into putting a set of diamond pistons into my car. They are 3.905 bore, 3.622 stroke, for 6.098 rods, with 2cc valve reliefs. What all is involved with this? Stock bore is 3.898 so I guess I'm looking at least a .007 overbore. Will the rotating assembly need to be rebalanced, any othe machine work? I also plan on putting in a set of katech rod bolts and maybe a few other things depending on $. Thanks a lot for the help.
12-07-2006, 01:13 AM
#2
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You will of course need to have the block machined and honed for 3.905 pistons as you mentioned. You should also get the rotating assembly balanced as the forged pistons will not be the same weight as the stockers. This is a similar setup as to what I am going with as nobody makes overbore pistons in cast.
12-07-2006, 02:22 AM
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I paid around 400 for the machining and balancing. Make sure they use a deck plate whenever they are doing the machining and shop around for a good machine shop. I got screwed by a reputable local shop before I found a good one.
12-07-2006, 09:24 AM
#6
FormerVendor
Beaflag,
Also make sure the piston pins are the same between them. The stock 6.098 rods use a metric .945 pin and the 6.125 aftermarket rods usually use the normal SBC .927 pins.
Also make sure the piston pins are the same between them. The stock 6.098 rods use a metric .945 pin and the 6.125 aftermarket rods usually use the normal SBC .927 pins.
12-07-2006, 01:21 PM
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Obviously the pistons are the majority of the cost. Go ahead and get something like this http://cgi.ebay.com/ebaymotors/H-BEA...61508368QQrdZ1
Not top of the line, but alot better than stock. If you are going to go to the trouble to get the engine reassembled, do it right.
Brandon
Not top of the line, but alot better than stock. If you are going to go to the trouble to get the engine reassembled, do it right.
Brandon
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12-07-2006, 02:20 PM
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I'm doing the same thing in a 6liter, but having a VERY hard time finding the right piston.
4.000 bore, 6125 rod, 3.622 stroke. majority of the pistons out there are 4.030, 4.060 but there are SOME 4.005.
4.000 bore, 6125 rod, 3.622 stroke. majority of the pistons out there are 4.030, 4.060 but there are SOME 4.005.
12-07-2006, 04:29 PM
#10
Originally Posted by xfactor_pitbulls
Obviously the pistons are the majority of the cost. Go ahead and get something like this http://cgi.ebay.com/ebaymotors/H-BEA...61508368QQrdZ1
Not top of the line, but alot better than stock. If you are going to go to the trouble to get the engine reassembled, do it right.
Brandon
Not top of the line, but alot better than stock. If you are going to go to the trouble to get the engine reassembled, do it right.
Brandon
12-07-2006, 05:10 PM
#11
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Originally Posted by Beaflag VonRathburg
This is kind of a special situation, because I'm getting these on a "clearing old stock" sale for $300. They're usually around 565, so this is saving me big money. $300 pistons with rings and pins, $400 balancing and machining, $75 bearings, $160 katech rod bolts, random fasteners / gaskets $350 = $1285. Plus the other random H/C stuff I throw in which is also going to be budget $850ish at the most. This should only be a temporary build to have some fun with. I expect the stock rods and crank to be able to survive easily, they're tough.
Brandon
12-07-2006, 05:27 PM
#12
Originally Posted by xfactor_pitbulls
Yeah I hear you. But especially if its something that isnt going to stay in the car it would make more sense to make it worth something to sell to the next guy. You already have good pistons, why not make the shortblock good for a 250 shot? Your money of course, just throwing the idea out. You can also add eagle or scat rods for about $350. Oh yeah, you said you are going to put in katech rod bolts, so subtract the difference from the rods since they come with them. So more like $250-$275 more, dont get why you wouldnt do it.
Brandon
Brandon
12-07-2006, 05:47 PM
#13
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Originally Posted by GuitsBoy
Where do you get your katech bolts for 75 - 100 bucks? Last i heard they were 158 + shipping. The difference dwindles down to under 200 extra bucks to forge the rods. well worth it. If it was me, Id kick my own *** for not forging the rods when i had the chance.
12-07-2006, 08:48 PM
#14
Where are you finding scat rods for $350? Cheapest I can find them is $429 with arp 8740 rod bolts, I'm not talking ebay either.
That does make sense, but I just planned on putting it into my other car as a dd. If I can find rods for cheaply enough I might go ahead and do it, especially if they come with rod bolts.
Originally Posted by xfactor_pitbulls
Yeah I hear you. But especially if its something that isnt going to stay in the car it would make more sense to make it worth something to sell to the next guy. You already have good pistons, why not make the shortblock good for a 250 shot? Your money of course, just throwing the idea out. You can also add eagle or scat rods for about $350. Oh yeah, you said you are going to put in katech rod bolts, so subtract the difference from the rods since they come with them. So more like $250-$275 more, dont get why you wouldnt do it.
Brandon
Brandon
12-07-2006, 10:26 PM
#16
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Originally Posted by pist0lpete
I paid around 400 for the machining and balancing. Make sure they use a deck plate whenever they are doing the machining and shop around for a good machine shop. I got screwed by a reputable local shop before I found a good one.
