replacing pistons and rods

[dan2288]

Right now I have stock pistons and rods. I want to build my motor sometime soon. Would it be ok to drop in weisco pistons on eagle rods If the bore and everything looks good? I dont want to overbore if I dont have to.

 

[viperlp01]

Well thats what you ussually do when you build and engine. I have seen engines built while they stayed in the car.. They did the hone and assembly while the short block was still mounted in the engine bay..

 

[98gsxtuner]

Well thats what you ussually do when you build and engine. I have seen engines built while they stayed in the car.. They did the hone and assembly while the short block was still mounted in the engine bay..

Thats exactly what I'm doing right now.

 

[95gstSAM]

Thats exactly what I'm doing right now.

Not trying to steal dudes thread but how much more difficult is to do a build with the block in the car? Are there shops that would do this? I dont have the time/skill/patience to pull my engine.

 

[dan2288]

okk, cool. It would be alot easier and cheaper that way. But dont aftermarket pistons need more room because they expand when they get hot, or no?

 

[Redwidow]

Not to Shut all of you down, But there are a couple reasons that you always want to have your block machined. One is because even if you can still see cross hatches that doesnt mean that you can see warpage. 4 thousandths is out of spec and that about as think as a hair. Personally I think that building an engine while the block is in the car is a very bad Idea. Yea its cheaper but in the long run its going to cost you more in the long run.

 

[skatershawn]

i dont believe he started saying he was going to rebuild it in the engine bay but do rebuild and not get in machined isn't the best way to do the job!! Its a fast cheap shortcut that can end up being bad!! Get it honed atleast!!

 

[tkelly27]

I did the rebuild in my car, but I was just doing a ring and bearing job. You don't even need to take the head or trans off to do all the bearings but the top crank thrust bearing.

You cannot put forged pistons in without having the block machined. They have a different expansion rate than a stock piston and you will end up with premature wear problems.

 

[My1GLaser]

You cannot put forged pistons in without having the block machined. They have a different expansion rate than a stock piston and you will end up with premature wear problems.

. Unless the bore is worn just the right amount and perfectly symmetrical, which would be a 1 in a million chance.

But seriously, taking a block to a reputable machine shop is pretty important...but not always necessary. Getting it hot tanked, cleaned, decked, bored and honed is critical to protect your expensive forged components and reduce headaches down the road.

Either build it quick and cheap and expect a possible problem down the road.

Or drop the cash and have piece of mind. That's my .02.

 

[spooled_u_1st]

You may be able to go with a 4032 aluminum alloy piston such as wiseco or mahle which doesn't require as much piston to wall clearance unlike the 2618 aluminum alloy like ross, je, ect...

You definately want to measure you bore sizes before anything.

I too would also suggest taking your block to a machine shop. Especially if your going to run a mls head gasket because you need a RA50 or better (smoother) surface.

 

[donniekak]

Forged pistons that come in standard size are made for a standard sized bore and are sized for the proper clearance. They are actually smaller than an oem standard sized piston. But, it is never a good idea to run them without checking the bore to make sure they are still cylinders and not cones. As for honing cylinders with the engine in the car, you better hope you get 100% of the honing grit out of the block or there will be trouble.

 

[brassc2007]

i just got done doin a motor build and yes doin it the old fashioned way would have been way easier, but if you are planning on boosting or building this for power at all then you should just take it to a shop and get the works done. Get the block cleaned and honed and decked, they can also make sure your crank journals are all straight. Nothing worse than someone with a motor that has say 500 miles and caked with grease it just makes ya look bad no offense.

 

[dan2288]

well if the bores all look good and I give it a good hone, then I think it should be ok. If the bores look good then theres no need for a machine shop to touch it. I will probly use a composite head gasket along with my arp's, as they can hold alot of boost.

 

[brassc2007]

that is true i would at least have them magnaflux it nothing worse then building a motor and finding out you have a hair line crack somewhere

 

[96eclipzGsT]

I have built a ton of engines. Just mic the cylinder make sure they are in spec according to the piston diameter, hone them out and put them in. Just don't break a ring or put them in backwards. Put a ratchet on the front of the balancer when done and make sure the engine spins nice a free. If you have the money though I would take it to a machine shop.