Well, after calling Wiseco a few times and talkin to several people,(the product knowlede wasn't there for a couple people) These are NOT "drop in" as stated. The only thing drop in about them is the use of stock rod length and bore. They are available in .010,.020 sizes. Well, with a title like "Junkyard Dog" and "drop in" That type of advertising would lead alot of people to believe these would be equal weight drop in pistons on a junk yard engine budget. This is not the case and is mileading,i feel. You will need to rebalance which makes these NOT a drop in. I know i was disappointed..... Do any of you guys know of an actual equal weight forged dish type piston for 5.3? Just thaught it'd be pretty cool to put your own boost friendly pistons on at home for the guys with 2005 and up floating rods.

What does a stock genIV 5.3 piston and pin weigh?

Wiseco Part # K0042XS std bore 3.780
piston weight 414g
pin weight 112g

 

Anyone?

 

There isnt any "drop in" pistons. Do it right, its not that hard or expensive.

 

I was going to literally drop them in on a build in the standard size. But I got a 6 liter instead.

Mike

 

I totally thought that's what they were too! Hell if a guy could buy and jam some decent slugs into a junkyard dog on the weekend, ls9 headgaskets and ching chong meow headstuds, that'd be killer!!!! haha

 

i would want to balance the rotating assembly....

 

Man im right there with you on not wanting to have to balance everything. I have a ls2 with a stock button end and im wanting to put my compstar h beams and weisco dish pistons in it. Ive measured the rods and they are so close im not caring about them but the pistons i dont know about. In a perfect world if the after market piston/ring/pin combo was just a tad over i would use my scale and lighten the forged piston up to match the same weight. Everyone tells me the forged stuff is lighter though, seems weird because they seem heavier in my hand. Also now that i think of it i think i upgraded to a big wrist pin maybe.

Im tearing my motor apart tonight(well going to start atleast if my wife will let me be) and ill measure my stock stuff and compare. Wont help you to much since im a 6.0 but atleast itll be a ball park figure.

Also for what its worth ive swapped my stock rods/pistons for eagle h beams/arp2000 bolts and some oddball piston/ring combo in my old ls2 before and the wrist pin was the wrong size on the rod, so i honed the rod big enough to fit the later larger wrist pin diameter. Installed it, with out weighing anything because i didnt know better at the time and i broke 800rwhp on a dynojet with a th400 and 9 inch and 17 lbs boost. Then raced it for nearly 3 years with 3 more lbs of boost and breaking into 5.xx 1/8th mile runs. Honestly over 100 1/8th mile passes and 10 1/4mile runs are 9.4-9.2 et's. Never broke, or had a problem and actually honestly was the best motor i ever had. All the bearings (clevite h's i think) looked almost new.

 

"The 5.3L engines all came with automatic transmissions, so they all had the 12552216 casting with the narrow flange. This is the same casting that was used in both the 5.7L and the 6.0L, but it’s balanced specifically for this application, so it has its own unique GM part number. We don’t know what the bobweights are, but our sample piston weighed 406 grams."

If that was true i can help you on how you lighten the forged piston to make it the same weight. Just your need a scale. But looks like you may be lucky.

I dont think im going to believe this or even know if that includes the pin but...
"All of the ’01-’04 cranks used the 12552216 casting with the narrow flange, just like the 5.3L and 5.7L, but the 6.0L pistons weighed considerably more (470 grams) than the ones used in the 5.3L and 5.7L engines, so the bobweights had to be different. These may even be two different versions of this crank because the rods used in the LQ9 motors weighed 36 grams more than the ones in the LQ4 motors."

http://www.enginebuildermag.com/2005...m-small-block/

 

Also with how you would have to lighten the forged piston since you have the scale and grinder you can make the weights of all the other pistons/pins/rings to make it more balanced. Rods also but they are tricky. They have this goofy fixture to measure the "big end" vs the "Small end". But were get into that later. heres a pic of that http://www.summitracing.com/parts/po...FfNxOgodvhcAIQ

But anyways the moral is your on the right path trying to get by on your own risk. I think people really just get told to do something 100 times and never really try to think into what they are being told. Also though who knows if the factory crank was balanced correctly, but i would rather trust them compared to my local machine shops. But again gm didnt think that the express van motor they were building would make over 1000hp one day either so who knows how balanced it was to begin with.

its your stuff though so who cares what others think.

 

So you bought forged rods and pistons and are going to take a grinder to them to save 2-400 in balancing?

 

I know theres going to be alot of people like you with comments like this, but if the rods,pistons,pin combos weigh the same you can argue with me all you want but im not sending them off. Ill just save that money and buy arp main studs.

 

my weisco piston weighs 481 grams btw its part number K0045X05 4.005 9.7cc dish

 

More along the lines of buying forged pistons then grinding them down

 

I like your style.
use your head, and do it yourself!

 

My local shop charges $150....

 

 

...plus money for each heavy metal plug...

 

i think the pistons are a waste of money since i bend the rods out of motors before i hurt pistons

 

^ gen. 4 rods?

 

No.... $150.