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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Forged E7ZE replacement

  • Thread starter Thread starter Boydster
  • Start date Start date Apr 10, 2011

Boydster

5 Year Member
Apr 10, 2011
301
20
39
Maryville, Tenn
Apr 10, 2011
#1
  • Apr 10, 2011
  • #1
Hi all, long time reader, first time poster.

Dropped a washer down the intake (I swear I never saw or heard it drop in there) and dinged the hell out of the top of the #1 piston. 87 GT 5.0 with forged E7ZE-6110-CA pistons, 101k miles. Original owner, by the way.

Dinged the Edelbrock head pretty good, too, but I can get that fixed.

I'm pulling the motor now, but am having a hard time finding a replacement piston without buying a whole brand new set. I know the TRW's aren't made anymore... does anyone else make a direct replacement that will still work with the other 7 cyl's being the factory forged pieces?

Part number would be much appreciated.

Am also posting up in Classifieds to see if anyone has a factory forged piston in good shape laying around...

Thanks for reading, and thanks for the Forum.
 

2000xp8

SN Certified Technician
Aug 8, 2003
8,015
1,612
194
NJ
Apr 10, 2011
#2
  • Apr 10, 2011
  • #2
Sounds like you are going to go through more trouble than it's worth replacing a piston on a 100,000 mile engine.

I'd buy an explorer engine, sell the gt40 heads and intake, use the shortblock in your car and be done.

The last guy i knew that dropped something in the engine pulled it out, repaired the head and found out the shortblock was worthless.
 

Boydster

5 Year Member
Apr 10, 2011
301
20
39
Maryville, Tenn
Apr 10, 2011
#3
  • Apr 10, 2011
  • #3
Well the shortblock is still in really good shape. Doesn't burn a drop of oil, can still see crosshatch in the cylinder walls, pistons are pretty clean, very minor carbon ridge can be removed with a fingernail... will find out more tomorrow when the engine comes out.

No power boosters, so I have no qualms about going another 50k on this motor, as long as nothing breaks. Ran good n strong before the washer incident.

If I got an Explorer motor, I'd have to do a rebuild before I planted it in the 87. Otherwise I'd do all that work and always be wondering how long it would last, if it was any good at all...

But thanks for posting up!
 

2000xp8

SN Certified Technician
Aug 8, 2003
8,015
1,612
194
NJ
Apr 10, 2011
#4
  • Apr 10, 2011
  • #4
Boydster said:
If I got an Explorer motor, I'd have to do a rebuild before I planted it in the 87. Otherwise I'd do all that work and always be wondering how long it would last, if it was any good at all...
Click to expand...

You are going to have to worry just as much about an engine you pulled a piston out of.

None of the 5.0 shortblocks ever seem to be the same once they are pulled apart, that's why i suggested the explorer shortblock.

How damaged is the piston? Normally a piston that is damaged enough to need replacement does damage to the cylinder wall too.
 

Boydster

5 Year Member
Apr 10, 2011
301
20
39
Maryville, Tenn
Apr 10, 2011
#5
  • Apr 10, 2011
  • #5
The piston was dinged pretty hard right next to the lower edge, but I see no marks at all on the cylinder wall. Seems to have gotten caught between the head and piston and didn't touch the wall at all before it broke apart. I can easliy see where the edges of the washer dug into the aluminum parts. I started to clean up the damage with a dremel stone, but it's too close to the edge and I think it's too deep to continue living.

I really think the aluminum parts took the brunt of the damage.

I guess I'll go for a full rebuild, since it looks like I'll be replacing a full set of pistons / rings /rod bearings anyways. Been a few years since I did one... a mexican 302 that I put in my '67 Fastback.

I'll rebuild / repair this engine cuz it's still the original 5.0 HO for this car. After 24 years, I think I'll try keeping them together.
 

giddyup306

Founding Member
Oct 22, 2002
3,041
2
59
Apr 11, 2011
#6
  • Apr 11, 2011
  • #6
I'm not sure why you want to keep it "original", fox mustangs are a dime a dozen, and there are loads of better-than-oe-parts out there.

However, if you want an OE part, your best bet is to find a NOS part on eBay. Some of your bigger dealers might even have one in the back of a parts room. But paying for one piston will cost you a fortune. Look at the GM v6's. Their rebuild kits came with 8 pistons and rings because it was cheaper (basically a 350 rebuild kit).
 

Boydster

5 Year Member
Apr 10, 2011
301
20
39
Maryville, Tenn
Apr 12, 2011
#7
  • Apr 12, 2011
  • #7
Thanks Mike. Yeah, I decided to replace all 8 pistons with aftermarket. Prob going to do a full rebuild, nothing extravagant (no spray or boost), just a nice, strong NA 5.0.

I fully expect the crank, cam and rods to be fine, so a good cleaning and some new bearings and rings should do her right up.

3 days ago, I was thinking of replacing just the 1 to only fix the damage and get it back on the road. Money and time, ya know? But the shortblock is out now, so I might as well do it right.

Sure was an expensive washer. Started out just changing valve covers...
 
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