Cascade Crew

1987_sportcoupe

So how do I do this? Never rebuilt an engine before. Probably easier to have a shop assemble my shortblock but I want to learn how to do it myself. Any tips are appreciated.

Alphius · Posted: Thu Jan 12, 2012 3:59 pm Post subject:

Can't balance a rotating assembly yourself. It takes a special machine.

Get a good book about engine assembly and you can probably put it together yourself.

1987_sportcoupe · Posted: Thu Jan 12, 2012 4:10 pm Post subject:

Ok so what exactly is balancing the rotating assembly? And I bought a good book a couple days ago that should help. My main bearings came in today so all I need now is pistons and rings to complete the short block

Alphius · Posted: Thu Jan 12, 2012 5:28 pm Post subject:

http://en.wikipedia.org/wiki/Engine_balance#Component_balancing

1987_sportcoupe · Posted: Thu Jan 12, 2012 5:38 pm Post subject:

Alright so I'm assuming that the short block has to be assembled in order to balnce it? Like I said this is my first time building an engine so this website and everybodys input helps out a lot

Alphius · Posted: Thu Jan 12, 2012 6:00 pm Post subject:

Yes, the components of the engine have to be assembled and spun, kind of like a tire balancing machine.

Part of balancing is making sure all the parts are the exact same weight, like all of the piston/rod assemblies. The other part is spinning it all up as assembled and getting rid of vibration via adding/removing metal.

chevymad · Posted: Thu Jan 12, 2012 6:05 pm Post subject:

The shortblock isnt completely assembled. Pistons are hung on the rods and the bearings installed. Then those assemblies are weighed. Then the crank is spun with bob weights hung on it to simulate those weights. Material is then added or subtracted from the crankshaft counterweights to balance the piston/rod assemblies.

Twilightoptics · Posted: Thu Jan 12, 2012 6:20 pm Post subject:

You don't install the pistons on the rods.

Each component is measured individually. Big end of the rod, small end of the rod, piston, wrist pin, ring pack, bearings.

Then those are compiled into the computer. The crank is spun, and the computer tells you where to add metal or take metal out.

1987_sportcoupe · Posted: Thu Jan 12, 2012 6:25 pm Post subject:

Any idea on cost of this? After I get pistons ill take it all in and have it done

chevymad · Posted: Thu Jan 12, 2012 6:48 pm Post subject:

Sounds like a newer or maybe just different system then i've heard of being used Paul. But in any case, you don't do anything until you talk to your machinist.

Alphius · Posted: Thu Jan 12, 2012 7:15 pm Post subject:

Twilightoptics · Posted: Thu Jan 12, 2012 9:37 pm Post subject:

Balance is about $200 alone.

aaron_sK · Posted: Thu Jan 12, 2012 9:45 pm Post subject:

1987_sportcoupe · Posted: Thu Jan 12, 2012 9:54 pm Post subject:

Pretty pricey to have one assembled I see. I may just have somebody with know how show me how to assemble it myself for a half rack and some pizza haha

iansane · Posted: Fri Jan 13, 2012 12:15 am Post subject:

BluFbdy · Posted: Fri Jan 13, 2012 4:31 am Post subject:

Just a tip you should check with a builder on your components, I threw in the towel and had my shortblock done by bowtie performance, pricey but its solid. Rebuild kits from summit or jegs are done in bulk and not matched from what I've been told, I got all new pistons and rods for mine and also had my block bored out because the cylinders were way off, if you haven't measured every single angle and are not absolutely sure they're within spec you can watch your investment sieze up on the first fire. I had a summit rebuild kit I bought, Paul at bowtie showed me the difference in weight between the pistons and how fragile they were, along with the difference in my cylinders. Its a costly investment but peace of mind and longevity are worth it to me, to have my block bored, new pistons and rods, decked and cleaned with assembly it cost me 900, Paul also balanced it closer than factory for me (not exactly a race motor) so I'm fine with the balance as long as its better than factory.

Certain things should be handled by professionals like this, I feel the same about car audio lol when people try to install their own stuff and royally screw it up I just shake my head because professionals have access to certain equipment and inside knowledge that the average person doesn't, granted car audio is not NEARLY as complicated as engine building but its the same concept.

I'd shop around though bowtie was cool and all but I'm cheap and 900 is a big debt in my pocket, I went off a reference from Luke and I believe al got his motor there as well (don't quote me in that) Paul is a straightforward guy but if you don't run on his schedule he can be kind of a jerk

1987_sportcoupe · Posted: Fri Jan 13, 2012 7:24 am Post subject:

You kne that's probably a good idea that way I can be sure that everythings going to work together and I will be 100% sure that everythings done right.

Twilightoptics · Posted: Fri Jan 13, 2012 8:31 am Post subject:

You can still save money on assembly. Have the shop do the machine work and balancing and have someone who knows what they're doing install.

1987_sportcoupe · Posted: Fri Jan 13, 2012 12:04 pm Post subject:

Ok so do you guys think I should just send it to the machine shop to have it balanced and have them check to make sure all measurements are right or just fork up the money and have the machine shop assemble my whole short block. I really want to save money here but at the same time want a reliable engine.

Twilightoptics · Posted: Fri Jan 13, 2012 12:45 pm Post subject:

Depends on what you're building. You need to have the mains checked and maybe line bored. Need to have the cylinders checked and maybe bored (pistons purchased to match bore size).

You really need to go talk to a machinist directly. He'll sit down with you and give you the low down on what's what.