87-93 Which year had forged pistons?

Michael Yount said:
Hypers are fine in the right application. They actually stronger than forged -- however, they're not as ductile. So when things go wrong in the chamber -- detonation or lean with nitrous for example -- a forged piston is more forgiving than a hyper. To oversimplify - forged pistons bend - hypers break. Because they're more brittle, when they let go they usually take out a bunch more other stuff. With a forged, you might just push a hole through the piston. With a hyper -- a lot more concomitant damage occurs.

I agree except for one point I've researched. Hypers are so much more brittle that they can break at the first sign of detonation. This is why you have to be careful to get the tune exact when using them with nitrous or forced induction. On the other hand it takes a lot more detonation to melt a forged. So when a forged does finally fail it will cause more damage. The best part of forged is that its more forgiving should the tune not be right.
 
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hypereutectics should suffice GREATLY and will perform just like forged and maybe even better, since they expand more due to heat and seal better against the cyl wall. preventing blowby.

but everyone says that they break under forced induction... so i'll go with that also....
 
Foxfan88 said:
hypereutectics should suffice GREATLY and will perform just like forged and maybe even better, since they expand more due to heat and seal better against the cyl wall. preventing blowby.
Actually hypers dont expand much at all, thanks to the silicone content. That is what allows them to fit the bores tight at all times.
Forged slugs are known for piston slap, etc because there needs to be slop in the bore for expansion of the slug.
 
Oh yeah, As Daggar knows, my mnemonic device for the oil pan and slugs thing is:

Grey is good
Black is bad.
 
Hissin's right.....the hypers are thermally VERY stable so they size them much tighter to start with.

Does anyone know for CERTAIN that the oil pan color is a pointer for piston type? It's only marginally helpful as so many of these engines have been rebuilt and re-painted.
 
I have a black oil pan (late 93) so no surprise. I wouldn't worry about my pistons. More about my block...

Get a good tune and either piston will be just fine!

Forged is more forgiving by a bit.
Hypers are lighter by a bit.
 
andrewsg said:
Interesting with the whole color thing... but eh.. my 86 has a black pan.. heh.. and my 89 did as well.. and they were both forged.. so eh?

Doesnt appy to the 86, only 87 - 93. Its not 100% foolproof method. Did you ever think a newer Engine may have got put into your 89?
 
1979-84 Part Number D90E-6110-AA Sand-cast Aluminum
1985 Part Number E4ZE-6110-SB FORGED ALUMINUM
1986 Part Number E6ZE-6110-BA FORGED ALUMINUM
1987-92 Part Number E7ZA-6110-CA FORGED ALUMINUM
1993 Part Number F3ZE-6110-AA FORGED ALUMINUM

Note: All pistons are sized for the 5 liter engine's four-inch bore. The 1986 versions are flattops. All other H.O. forgings (and the GT-40 hypereutectic castings) have two sets of valve reliefs in their domes. Wrist Pins are 0.912-in. Diameter, float-fitted in their piston pin bosses and press-fitted in their rods.
 
Reviving this post, my 87 pistons have casting number E7ZE-6110-CA. Was the E7ZA above a misprint? Also I thoght no 93's had forged as mentioned above? BTW, I went to the machine shop today, the owner thought I was nuts when I told him 5.0 HO's had forged. He wouldn't belive me. I was hoping to get a hone job and slap new rings in it(low-buck rebiuld), but he basically was rude saying I was trying to get away with doing nothing, and he was sure he would have to go at least 30 over without ever seeing the block. Now I am frustrated and don't know which road to proceed down.
 
What machine shop?

Don't go there again, they are retarted, re-ringing is fine if the bore wear is with in spec, and if the machine shop doesn't know that 5.0's have forged pistons, and that you have to go 30 over without seeing the engine, I wouldn't trust him to put cam bearings in.

measuse everything out to see what you need and go from there, don't buy what you don't need.

Dale at DG machine in Auburn is a great guy, rob at action auto is a good one too. Jim Greens used to have a great machinest named Dave, but I think he moved on, so I am not sure what the status is there.

I would tell you to go to Honest Performance in renton, but we are long gone

Rest in Peace
 
I won't say the shop yet, I think I might end up having something done there. I would measure the bores myself, but I don't have a bore gauge lying around. I'm hoping if I just take the block there, he will at least check it out and see what the taper looks like. Another thing though, he said he wouldn't hone it without cleaning the block first. That seems a bit unnecesarry to me. Where is this Action Auto and Jim Greens at?
 
my local machine shop was very impressed with the condition of my 87 engine when I brought it in. I tore it apart at 258,000 miles and all we had to do was hone the cylinders and polish the crank (along with all the proper cleaning stuff). The cylinders & crank just had .001 wear after all those hard(;)) miles.
 
Action is in shoreline, and Jim Greens is in Lynwood.

http://www.action-auto.com/content/shop.html

To aviod cleaning charges put the bare block in the back of your truck and take it to the brown bear car wash, with dish soap, spunges, and the high pressure hot water they have there it comes out looking like a million bucks. Engine brushes arnt bad to use either(don't foget to dry and lube up afterward to keep rust at bay)

This can not only save you money, but make the machinest like you (they really hate getting nasty stuff dropped off). It is Std operating proceduce to clean before the do any work (they are doing presision work they don't want greas and oil every where)

I have found the money spent on engine measurring tools have saved me money in the long run, so keep that in mind if you are going to build more than one engine.

but seriously there are some really bad machine shops, avoid them with your life, they will end up costing you money.