Heads off - stock cylinder walls/pistons? (pic)

[GT_Rich]

I'm curious, but I have no previous experience so I figured I'd ask the experts....

I was told when I bought this car that the motor was rebuilt 20k miles ago. It had a B-cam put in at that time, and the idle verified that! I'm in the process of putting on TW heads, and I just got the heads off tonight.

This pic is from right after I pulled the driver's side head. I haven't cleaned anything yet. This piston seems too clean for me to believe the motor wasn't rebuilt. I've also read here that the walls will have obvious cross hatch from the factory, which leads me to believe these have been honed.

Any input would be appreciated. One last thing - the only marking on my lifters is DP9. Are these stock or aftermarket?

Thanks!

 

[dragnazz5.0]

doesnt look stock to me just because of how clean it is...like you said. it could be a very clean stock motor or it could be a rebuilt motor. the pistons dont say .030 which would mean it was definetly bored....but it could have just been honed and re ringed.

 

[25thmustang]

Honing and reringing is nothing bad to worry about, so long as the hone wasnt too much. One of my short blocks was honed out a good deal, and makes a little more power than the bone stocker!

 

[JChalfan]

If it had been rebuilt (and honed) 20k ago, I would think you would be able to see crosshatch in the cylinder wall. But that piston does look pretty clean.

Different people have different ideas of what "rebuilt" means. To some people it means new rings, bearings, and gaskets. To some it means new pistons, crank turned, block bored.

It's hard to tell from a pic. If it had been bored, you would expect to see .030 stamped into the top of the piston, like dragnazz said.

How many miles does the car have? Can you catch a finger nail on that ridge at the top of the cylinder?

Jeff

 

[GT_Rich]

Jeff,

The car has 120k mi on it. I can catch my fingernail on that ridge if I go slow and try to. The ridge looks to be a small build up of carbon to me, is that correct?

Thanks for the replies...

 

[dragnazz5.0]

yeah...that is a carbon ring. i think that motor was atleast honed and reringed. because that piston is way to clean for 120k and the ridge at the top is too light for 120k

 

[uedlose]

It looks like a aftermarket piston to me. are the valve reliefs bigger on one side then the other or is just the way it looks in the pic.

 

[Flavadave4]

Theres no way that is original equipment.......as long as it runs smooth and doesnt smoke you'll be fine!

 

[2002BLGT]

I dont see a ford part number in the middle of the piston which lead me to think its maybe be stock replacement stock bore piston , which could possibly be a cast replacement , so if it were me I would finish the tear down and make sure you know what you put back in it

 

[FeTTstang]

If it had been rebuilt (and honed) 20k ago, I would think you would be able to see crosshatch in the cylinder wall. But that piston does look pretty clean.

Different people have different ideas of what "rebuilt" means. To some people it means new rings, bearings, and gaskets. To some it means new pistons, crank turned, block bored.

It's hard to tell from a pic. If it had been bored, you would expect to see .030 stamped into the top of the piston, like dragnazz said.

How many miles does the car have? Can you catch a finger nail on that ridge at the top of the cylinder?

Jeff

The top of the piston does not nessisarily have to be staped with .030, many dont. From the factory I could see definite crosshair pattern on mine.

 

[Flavadave4]

I had mine apart not to long ago, with almost 80k I could still see the crosshair patern on the cylinder walls.

 

[NKau]

Going from memory, that looks like the factory forged trw piston to me, but I can go find one to look at out at my parents and get back to you if you're curious. It was probably just refreshed with new bearings and rings, which is nothing to be afraid of. I just had a 150K shortblock gone through (this thing was BEAT), and there was no significant bore wear; was able to get away with just a hone, and re-ringing the pistons, and replacing all bearings which is all I wanted to do. No reason to spend $$$ on an overbore and oversize pistons if you don't have to. I suppose if you were really worried you could have a leak-down test run on it, but I don't think you have any reason to be concerned.

 

[Red88 RICK]

Is the head gasket good cause wen anti-frezze gets into the cylinder it will "steam clean" the piston and its sroundings.

 

[GT_Rich]

If someone has a pic of a stock forged piston, I'd love to see it.

The valve reliefs measure 1.20 at the longest chord and are equal in size at all four locations.

 

[Red1990Lx]

Looks like you may have some "garbage" between the piston and the cylinder walls. May wanna take a shop vac with some tubing and suck that crap out before final assembly. Prolly will burn out before anything happens, just a precaution.

 

[onefstsnake]

that would be a stock piston.

But the engine I bought has hypers in it, so thats why the "hole" thing is different.

 

[aleborjas]

those are the stock pistons!

 

[dtlionsfan]

I just tore down a 60k stocker with ford headgaskets that had 4 pistons w/ ford part numbers for forged 87-92 piston on top and 4 that had no numbers on top and a "trw" cast into the bottom.Yours is an exact match.Weird.

 

[Idwitheld-1`]

I just did heads on a stock motor that had never been apart with 130K (original miles). Looks exactly the same as yours.

Head had gasket failure to coolant passage. Was not "steam cleaned" but looked dirtier with yellow coolant deposits.