Since the head is already my block and I am going to turbo the engine, I thought I would look at putting Eagle connecting rods and pistons into the engine. But I don't want to remove the block from the car.

Can I simply remove the oil pan from below, and change the rods/pistons from underneath the car - has anyone done this and how easy is it? Steps/instructions would be awesome.

Thanks!

 

So this is a photo of a DSeries from underneath, oil pan removed; it looks very much like it would be possible; what structures/would need to be removed - the oil pump? Looks like the end of the rods where they attach to the crankshaft are accessible.

Tips/thoughts? Thx

 

I would be very concerned about getting the rings in correctly, the proper tool would not work from underneath. You may also have clearance issues with a forged rod, would not want to try to resolve that from underneath.

 

Has ANYONE successfully pulled this off and/or contemplated doing this?I figure I'm already halfway there with the head off, but I don't have the space or means to pull the block out right now - I guess i COULD if I was really determined but want to see if this is possible first.

 

you cannot take piston off from the bottom of the block.

 

The pistons and rods would come out of the top since the head is off the block right now, would I be able to connect/disconnect the connecting rods to the crank from underneath the car?

 

yeah you will but then you will realize that you should have take the engine out of the bay. Its easy loll and ******* worth it. Working on an engine with an engine holder is awsome

 

The cylinders need to be properly machined (bore/hone) for the new pistons and rings. That requires taking the block out and completely disassembling it, and taking it to a machine shop, with your new pistons.

 

Yes the pistons/rods can be removed with the block still in place. The crucial thing is that the new eagle rods may require the block and/or girdle to be notched for clearance. Then there's the possibility of an overbore being required (I'm with "F22Master" on his advice). The honing can be done with the block installed but that's given that the bores are within spec but I still wouldn't advise anyone to do it this way.

For the record, I have done a stock rebuild with the block still installed in the car but it was soooooo much easier doing it with the block on a stand for my other car.

 

Thanks for the info, I have the pistons and rods on order - see what happens, I like to pull off impossible feats lol..

So why would I need to have the cylinders re-bored if they are 75mm and the pistons I am getting are rating at 75mm as well? Wouldn't they simply fit in as the stock pistons did with new rings? Especially if there is no scoring or issues on the inside of the cylinder walls.

Thanks!

 

Because to properly assemble an engine (that you want to last...) all of your clearances need to be measured and checked down to the ten thousandth of an inch (x.xxxx). Sure, they are both "75mm", but I assure you, neither the pistons or the bore are actually a true 75mm.

Depending on the wear on the engine, the cylinder walls could be as much as .003" or more oversize. So when you put in your "75mm" pistons into your "75mm" bore, the pistons will slap around and make a bunch of noise and destroy themselves and the bore in very short order...

So sure, you could slap them in and hope for the best, but that isnt even half-assing it, thats just being an idiot.

Oh, and I havent even gotten into the needed crosshatch on the walls for the new rings to seat properly...

 

^He covered the specifics but to give a personal example, that second motor I put together was 75mm at the top of the bore but you could see the original pistons leaning halfway up in the bore (egg shaped cylinder walls). There was no way I was going to install stock sized pistons and feel confident. I ended up sending that block to be sized for the new oversized pistons I had ordered. If you can cancel the pistons you ordered I'd do it and/or ask for the next size up. A competent machine shop will ask you for the pistons first so that they can match them up to each specific cylinder when they bore/hone everything.