JE vs stock pistons

[nickel and dimed]

hey

I am currently rebuilding my engine and I have a choice between some JE pistons and stockers from toyota. The JEs are only $10 more than the stockers per piston ($127 canadian per piston from toyota). The thing is my mechanic is weary of aftermarket and trusts toyota through and through as it has proven itself to him several times. I am eventually going to be putting 400ish or more hp in the car and would like the some input. I am getting all new bearings and rings, a MHG, ARP head studs and egr block off plates install at the same time. Plus the block is going to be honed, decked machined and all that fun stuff (my poor wallet) :cry:

BTW I have a 1987 supra turbo

Please I need to make a decision soon and need some help and info comparing these pistons and what people have thought of these products soon as I need to decide. :1zhelp:

Thanks for all the help

 

[GrimJack]

Either one will do fine for 400 ponies.

The JE units are without a doubt far superior, and for that kind of cost difference I'd buy them in a heartbeat.

 

[tubbie]

Definetely JEs for only $10 more.........
You'll never know when you might get the itch for more power.

 

[bigboostedmk3]

I would defintely go with the JE's as well but if you are doing that and putting in forged rods you should put the forged rods in too as well as all the ARP hardware. Just my 2 cents

 

[kamil]

JE :bigthumb:

 

[RM777]

JE :bigthumb:

:sonic:

 

[Stretch]

I like the JE's. They were so shiney when I got them...
eric

 

[nickel and dimed]

ok I think there is a general consensus on this, but how is the reliability of the JE's as far as working with stock rods, and not overboring, as far as I understand I can get them in stock size

btw those JE are shiny!

 

[Zach]

You'll want to bore the block for the specific size of each piston. There's no way to do aftermarket pistons properly without boring the block to the proper clearances.

 

[Stretch]

You only really need to overbore if your walls are pitted, or damaged and can't be cleaned with the honing machine. If you buy overbored pistons from say JE and you specify 20 thou over you get all 6 20 thou over, they are precision forged and are all the same dia. You are correct in the sense that the machinist does need the pistons to double check that they are of the proper clearance if and when he bores the cylinders out tho. To ensure optimal fit.
eric

 

[nickel and dimed]

Yes that makes sense. But the question is about the reliabilty. The thing is my mechanic is very weary of aftermarket products. I trust him because he has worked on 7m-gte's before and has a good rep. I realise that JE is good, but how good when for about the first two years I will only have about 320-350 hp in the car. I want the reliabilty and since that I wont be getting forged rods, is this a good set up?

what is the life of forged pistons compared with factory units?

if i still have factory bore, will i need to have the cylinders honed to compensate for thermal growth of the forged units?

any insights are appreciated!

and i suck and have to get stanzaspeed to type my posts

 

[Stretch]

Honing the cylinders only adds scratches to the walls so that when you fire it up for the first 20 miles or so the oil sticks better and the rings have something to scrape against so that they seat properly. Boring is when they enlarge the piston cylinders to fit larger dia pistons. If your current walls are fine according to your machinist then honing is all you would need.
eric

 

[nickel and dimed]

Ok thank you. I have slight scoring on the cylinder walls and it may need only a honing job but may need boring. Which I am not sure yet.

The other question that I require an answer to is, do I need to overbore the clyinders to compensate for thermal expansion and if so how much?

Is this set up that I am currently looking at (forged pistons and stock rods) a good one and has anybody tried it, or currently using it? If so does it work well, any problem? Has anybody heard of any problems with this set up?

Thanks for all the help

 

[kamil]

This is honing...

 

[Eriol]

JE pistons weigh 293 or 298 grams, depending on whether you go .020 or .040 over. I can't find a number for the weight of the stock pistons at the minute, but I did find it once and figured the difference -- IIRC, a set of 6 JE pistons was about 2 and a half pounds lighter than a set of stockers.

Remove corresponding counterweight from the crank, and you've saved yourself 5 pounds of rotating mass -- which is fairly significant.

As far as strength goes, I've heard a few people with fairly high-HP MKIIIs vouch for the stoutness of the stock pistons. They always say that it's more important to tune conservatively (read: rich). I couldn't speak from personal experience, though, as I have none.

 

[miggles]

For teh win!!11!
The rings are gas nitrided btw not moly.

Hope it helps your decision. :icon_bigg

 

[bensn8]

For ten dollars more per piston, go for the JE pistons.

 

[csnow]

I realise that JE is good, but how good when for about the first two years I will only have about 320-350 hp in the car. I want the reliabilty and since that I wont be getting forged rods, is this a good set up?

what is the life of forged pistons compared with factory units?

If you are going to be under 400 hp, stay with the stock pistons. A forged piston will not last as long as a stock piston...period. You will never get 150K-200k miles on a set of forged slugs. That is why auto makers don't put forged pistons in factory vehicles. Not to mention, it will sound like a diesel when its cold unless you coat them. If you are going to run high boost in a high horsepower motor, then by all means get forged. I am not a fan of overbuilding a motor just because you "may" want more. Sounds like you want slightly over stock performance with long-term daily reliability. The factory shortblock will give you that and more. "Onceandgone" and "Dr J" are both running factory short blocks with over 425 rwhp with no problems. (Let the flaming begin)

 

[rakkasan]

If you are going to be under 400 hp, stay with the stock pistons. A forged piston will not last as long as a stock piston...period. You will never get 150K-200k miles on a set of forged slugs. That is why auto makers don't put forged pistons in factory vehicles. Not to mention, it will sound like a diesel when its cold unless you coat them. If you are going to run high boost in a high horsepower motor, then by all means get forged. I am not a fan of overbuilding a motor just because you "may" want more. Sounds like you want slightly over stock performance with long-term daily reliability. The factory shortblock will give you that and more. "Onceandgone" and "Dr J" are both running factory short blocks with over 425 rwhp with no problems. (Let the flaming begin)

Why do you say forged pistons won't last as long as cast? I disagree, and the reason automakers use cast pistons is cost, and nothing more.

 

[Stanzaspeed]

i beleive that is one reason he is concerned about going forged. he is currently a student and as of yet this is his only vehicle. its down for now with this rebuild so he dosnt want to do another in a few years while still in school.

for his goals stock or maby a set of stock pistons with coatings would be fine and dandy, i think he just wants to be 100% confident that freak ocurrances aside, this motor wont go boom.

oh, and dustin ill try and drop by the university tonight :icon_razz