White_LightningZ

iTrader: (1)

doesn't seem that difficult the only thing I am worried about is the balancing of the assembly.

Are there any forged pistons and rods that are around the same weight as stock to avoid having to rebalance the assembly? Could I just use a scale and take off material from the new pistons to match the weight of the old?

Trying to save money here (if possible) the only reason I am considering this is to try to let the lt1 live on 9-10psi of sc boost. If I can't do most of this myself I will probably scrap the idea.

any idea on cost to balance the assembly? I assume the shop would need the whole motor for this?

SincalT/A

iTrader: (16)

Balancing the assembly is not to hard.I used a food scale that i bought at Target.Just remember to keep your rod and piston combos within 2 grams of each other.There is all kind of info on the web to show you where to take material off to balance the assembly.

machinistone

If you put main studs in the block, you will need to have the block line-honed. The studs will distort the line bore differently than the bolts.

Take the rotating assy to a shop to be balanced correctly. They will need: Crank, rods, pistons, rod bearings(1 set), rings, flexplate(or flywheel), damper&hub.

Should be $250-350 depending on labor rates in your area.

You will also need to have your bores checked to make sure the piston to wall clearance will be ok with the new pistons, and at minimum have a kiss-hone done on the cylinders for the new rings.

SincalT/A

iTrader: (16)

Well if you are going to go through the trouble of a machine shop.Since they are the only ones who do things right ha ha. You may as well bore the block with torque plates(since you will be under boost and looking for proper ring seal).I still recommend you assemble the block and balance the rotating assembly ie(pistons,rings,rods) by yourself,because sometimes the machine shops arent as critical as you can be.You will need the crank,balancer,and or flexplate flywheel neutral balanced by a shop.To give you an example why i stress assembly of your own block.I had a reputable shop build my engine once.They failed to check or inform me that i had a bad oil pump drive gear.I lost that engine because of that one small overlooked part.I would have caught this if i was doing the assembly because i inspect everthing that i install very carefully.They also charged me for a broken oil level sensor that i later found was there fault.If you have ever taken a pan off an lt1 you will know what i am talking about.I know some things need to be done by a machinist shop but not everything. Anyways I will say this no one else cares as much as you do about how well and how long your engine will last.In the end shop will blame it on being a race engine and you my friend will be back at square one.So always check,check and recheck your parts it doesnt hurt anything.

machinistone

Don't say all shops are bad because of the few. All of our motors are done one at a time, with as much care and attention that we would put into our own personal motors. FYI: We warranty our race motors too

SincalT/A

iTrader: (16)

I never said all shops are bad.I did say sometimes shops are not as critical as you can be.Meaning mabe a guy has a bad day and misses something or is not as precise in a measurment.It happens to the best of us.Btw what shop do you work out of?

PortPros1

Just so you know balancing the pistons and rods correctly takes more than a food scale. You must find the small end weight of the rod, which will be reciprocating weight. You must find the big end weight of the rod, which is rotating weight, and do the calculations correctly. You need piston weight, ring weight, locks and pins. You also need to add in weight for oil. We balance our rotating assembly’s to zero; our scale goes to a tenth of a gram.

Spend the money and have it done correctly, we charge $250.00.

SincalT/A

iTrader: (16)

I didnt get into the specifics of balancing.I said to go on the web and acess the info(it is out there).The food scale I bought was calibrated and it was dead nutz on.What equation do you use to take oil weight into account?What would be your opinion on how worse or what side effect would happen if his assembly was lets say 1 to 2 grams out of balance on each piston rod combo?Just curious and hoping to learn somthing new.

machinistone

Not a sponsor - not looking to get banned.


We use 4g as the oil allowance.

You cannot just remove the weight from the rods, you need to know where to do it at, as mentioned above you are effecting rotating and reciprocating weight depending on where the weight matching is done.

SincalT/A

iTrader: (16)

Yes, i know where to take material off.What city do live in?I might be able to show you what a garage balanced & assembled engine can do.

machinistone

I don't doubt that you can balance the parts correctly if you know what you're doing. But without a spin balancer your only going to have balanced parts, and not a balanced crank.

I built my first engine as a kid in my bedroom, so I don't have a problem with home assembled motor.

SincalT/A

iTrader: (16)

Your right!Point is if you want to try it go for it you might save yourself some money.You do need to you realize the consquences and except them if things dont go your way.No matter what good luck to the OG OP and sorry for the hijack.

SincalT/A

iTrader: (16)

[QUOTE=machinistone;7902751]Not a sponsor - not looking to get banned.
Not a sponsor huh?I dont want to get into where l found that info.I respect who you work for but,please don't insult the little bit of intelligence i do have.

machinistone

I must be missing something here...

SincalT/A

iTrader: (16)

Well then maybe i am mistaken.l seen a post of yours claiming that you worked for a sponsor of this site.If you dont then disregard what i said.

machinistone

Wasn't a post by me, I've never said that.

SincalT/A

iTrader: (16)

Then someone is using your account check your post history on 3/26/07.Thats my Birthday too how ironic!

machinistone

3/26/07

I said "I'm with Katech" - as in "I agree with him"



Last I checked, they are not located in Northern California.

SincalT/A

iTrader: (16)

The wording of the sentence seemed to implie that you did.Sorry about that anyway.